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Poor less likely to be screened for colon cancer (Reuters
Health-25/07/2005)
People who are poor, uninsured, born outside the U.S.
or smokers are less likely to be adequately screened for colorectal cancer,
according to the results of a new survey of nearly 10,000 New Yorkers. Based on the findings, the researchers estimate that nearly 1 million New
Yorkers are at risk of developing colorectal cancer that will not be
detected by screening. Approximately 50,000 Americans die every year from colorectal cancer.
Research shows that screening tests can reduce the death rates by finding
abnormalities before they become cancerous. Still, significantly fewer
people get screened for colorectal cancer than for cervical or breast
cancers, and in New York City, only one third of the people with colorectal
cancer are diagnosed in the early stages of the disease. Currently, experts in New York recommend that people 50 or older undergo
colonoscopy every 10 years.
Dr. Lorna E. Thorpe of the New York City Department of Health and Mental
Hygiene, and colleagues conducted a randomized telephone survey of 9,802
adults living in New York City, asking if they were ever screened for
colorectal cancer. The findings are published in the journal Cancer. The investigators found that 55 percent of participants 50 years old or
older had been screened recently, and 42 percent said they'd received a
colonoscopy within the past 10 years. However, some people were less likely to be adequately screening than
others. For instance, people who were poor and Asians were less likely to be
screened for colorectal cancer. Current smokers, non-exercisers, and people
born outside of the U.S. were also less likely to report being screened for
colorectal cancer.
Non-Hispanic blacks and women were more likely to say they'd gotten
checked for the disease with a fecal occult blood test, rather than a
colonoscopy, which is considered the "preferred colorectal cancer screening
test," Thorpe and her team write. "Screening tests for colorectal
cancer are highly effective for early cancer detection, which results in
earlier stage diagnosis and reduced mortality. An increase in colorectal cancer screening rates to the levels seen for
breast and cervical cancer screening would result in significant reductions
in colorectal cancer incidence and mortality."
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No Evidence Calcium Fights Colon Cancer (HealthDayNews-20/07/2005)
Calcium
supplements may help prevent the development of polyps that can lead to
colorectal cancer, but there's no evidence calcium actually prevents the
malignancy itself, researchers say. In a review of two earlier studies involving more than 1,300 individuals,
Israeli researchers concluded that calcium supplements provide a moderate
protective effect against development of colorectal adenomatous polyps --
small, usually benign polyps found in about 30 percent of middle-aged and
older Americans. However, "this does not constitute sufficient evidence to recommend the
general use of calcium supplements to prevent colorectal cancer," the
investigators concluded. Their findings appear in the current issue of the
journal The Cochrane Library.
Previous research in animals and surveys of people with high-calcium
diets suggested that the mineral may offer some protection against
colorectal cancer, one of the leading cancers in both men and women. "Calcium supplementation is relatively cheap, likely to be safe, readily
available and has other positive metabolic effects on conditions that occur
with aging," such as osteoporosis, high blood pressure, kidney stones and
weight gain, Dr. Anca Zalmanovici, one of the review authors, said in a
prepared statement.
If further studies do confirm that calcium is effective, it could be
given to people who've previously had polyps and are therefore at increased
risk for colorectal cancer, the review authors said.
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Chinese most prone to colorectal cancer in Asia (Reuters18/07/2005)
A study spanning 14 cities across Asia has found the highest incidence of
colorectal cancer among ethnic Chinese, a trend which researchers in Hong
Kong blamed on a more westernized diet. Between October 2004 and April 2005, doctors performed colonoscopies on
5,055 people and found polyps in 19.4 percent of the subjects. Of these,
four percent had cancer. A further analysis found that colorectal polyps and cancers were found in
more than 18 percent of ethnic Chinese, followed by just over 12 percent of
Indonesians, 12 percent of Malaysians, 10 percent of Thais and eight percent
of Filipinos. Ethnic Indians were the healthiest in this regard, with only five percent
suffering the same condition.
A leading researcher in the study blamed the phenomenon on the genetic
makeup of ethnic Chinese and their changing diet. "The prevalence of colorectal polyps and cancer among ethnic Chinese is
very high, as high as in Caucasian populations," Leung Wai-keung, professor
at the Chinese University's Institute of Digestive Diseases, told Reuters in
an interview. "Our belief is that the Chinese genetic makeup is very
susceptible to colorectal cancer but this race has been protected by
traditional Chinese diet. But now, with lifestyle changes, a westernized diet, this genetic
susceptibility has been brought out," he said, adding that diets rich in fat
and red meat were the chief culprits.
Asked about the growing popularity in Asia of weight-loss programs from
western nations which advocated diets that were low in carbohydrates and
high in fat and meat, Leung said they would have to be followed over the
long term to be harmful. The study covered the cities of Guangzhou, Hong Kong, Delhi, Jakarta,
Fukuoka, Kitasato, Kurume, Seoul, Kuala Lumpur, Manila, Singapore, Taipei,
Kaohsiung and Bangkok. Among ethnic Chinese examined in the survey, researchers found those in
Hong Kong the most susceptible to advanced colorectal polyps and cancer --
11 percent of them were diagnosed with the condition. Eight percent of Chinese in the southern Chinese city of Guangzhou were
found with the illness, compared to four percent of ethnic Chinese in
Singapore and just over two percent of ethnic Chinese in Taiwan. The study also found that the incidence of colorectal problems was
highest among people over 50 years old. "If you are above 50, we would advise some kind of screening," Leung said
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Sigmoidoscopy Helps Catch Colon Cancer-(HealthDay News-05/07/2005)
Patients have a high acceptance of flexible sigmoidoscopy screening
for colorectal cancer, according to the results of the initial colorectal
cancer screening of thousands of volunteers in the Prostate, Lung,
Colorectal and Ovarian cancer screening trial. The trial is evaluating the effect of flexible sigmoidoscopy screening on
colorectal cancer deaths when the screening is used once and then repeated
three to five years later. Of the nearly 65,000 volunteers who had flexible sigmoidoscopy screening,
at least one polyp was detected in 15,150 (23.4 percent). Of those, almost
75 percent had follow-up lower endoscopy. Cancer and adenoma detection rates
were similar to those in other studies.
The researchers, from the University of Pittsburgh Cancer Institute, said
the high acceptance rates and observed detection rates in this group of
volunteers should approximate the results that could be expected from a
flexible sigmoidoscopy screening program in the general U.S. population.
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Bowel cancer risk higher for men with diabetes-(Reuters
Health-05/07/2005)
Having diabetes apparently raises men's risk
of developing colorectal cancer, Swedish researchers report. As lead investigator Susanna C. Larsson told Reuters Health, "Our
findings suggest that colorectal cancer may be added to the list of diabetes
complications." Ms. Larsson of the Karolinska Institute, Stockholm, and her colleagues
note in the journal Diabetes Care that some, but not all, epidemiological
studies have detected an increased risk of colorectal cancer in people with
diabetes.
To investigate further, the researchers followed 45,550 men who were
enrolled in a population-based study in 1997 when they were 45 to 79 years
of age. During an average follow-up of 6 years, there were 411 cases of
colorectal cancers. After factoring in age and other variables, the
researchers found that diabetes was associated with a 49 percent higher
likelihood of developing both colon and rectal cancer. These findings, the team concludes, "support the hypothesis" that high
insulin levels or factors related to insulin resistance may play a role in
triggering colon cancer.
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Hispanics, Blacks at Raised Colon Cancer Risk-(HealthDay
News-27/06/2005)
Members of Hispanic, black and other U.S.
ethnic groups face a 10 to 60 percent greater risk of being diagnosed with
advanced colorectal cancer and a 20 to 30 percent higher risk of dying from
the disease compared to non-Hispanic whites, a new study finds. The study, by investigators at the Fred Hutchinson Cancer Research Center
in Seattle, reviewed data from the federal Surveillance, Epidemiology and
End Results (SEER) program. Researchers compared colorectal cancer stage and
death among people from 18 different racial and ethnic groups.
They found that blacks, Native Americans, Asians/Pacific Islanders and
Hispanics were more likely than non-Hispanic whites to be diagnosed with
advanced colorectal cancer. Blacks, Native Americans and Hispanics faced a
greater risk of dying from colorectal cancer compared to non-Hispanic
whites, while Asians/Pacific Islanders were at a lower risk. There were variations within these broad racial categories. For example,
among Asian/Pacific Islanders, the risk of stage IV colorectal cancer and/or
death was lower for Americans of Chinese, Japanese and Indian/Pakistani
descent but higher for Filipino Americans and Hawaiians, compared to
non-Hispanic whites.
Among Hispanics, the risk of stage IV colorectal cancer and/or death was
similar for Cubans and Puerto Ricans but higher for Mexicans and
South/Central Americans compared to non-Hispanic whites. "We observed numerous differences in the risks of advanced-stage
colorectal cancer and mortality across individuals in different
Asian/Pacific Islander and Hispanic subgroups," the researchers wrote,
suggesting that experts need to take these variations into account when they
evaluate cancer risk in minority populations.
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Western and Japanese diets up colon cancer risk-(Reuters
Health-23/06/2005)
Both the meat-laden "Western" diet and the
traditional, salty diet of the Japanese apparently increase the risk of
colon cancer -- at least for women -- findings from a large study suggest. Researchers in Japan found that among more than 42,000 adults followed
for 10 years, women (but not men) with either a Western pattern of eating or
a diet heavy in traditional Japanese foods like salted fish and pickled
vegetables had a higher risk of colon cancer compared with women who were
deemed healthy eaters.
For their study, the investigators defined three different dietary
patterns based on survey respondents' reported eating habits. One was dubbed
the Western dietary pattern, and was marked by high intakes of meat,
poultry, cheese and bread and butter. A second category, the "traditional"
dietary pattern, was built around rice, miso soup, salted fish and pickled
vegetables. The third dietary pattern was the "healthy" one, and it included high
amounts of fruits, vegetables, soy products, beans and dairy. Overall, women whose diets were the most Western had more than double the
risk of developing colon cancer as women with the least Westernized diets.
Similarly, women who ate the most traditional foods were twice as likely as
those who ate the fewest to be diagnosed with colon cancer.
The healthy eating pattern was not linked to colon cancer risk at all. Dr. Mi Kyung Kim and colleagues at the National Cancer Center in Tokyo
report the findings in the July 10th issue of the International Journal of
Cancer. A number of studies have suggested that diets high in animal products and
saturated fat may raise the risk of colon cancer. A large European study
published last week found that people who regularly ate hefty servings of
red or processed meat had an elevated risk of the disease, as did people who
got little fiber in their diets. In that study, fish consumption in general was tied to a lower risk of
colon cancer.
In addition, heavy consumption of salted fish and vegetables, staples of
the traditional Japanese diet in the current study, has been tied to higher
colon cancer risk. The reasons are unclear, but research in lab animals has
shown that substances in salt-preserved foods called nitrosamines may
promote cancerous changes in cells, Kim's team points out. Why the various diets in their study were linked to colon cancer only
among women is uncertain. It's possible, the team suggests, that smoking and
habitual drinking -- two habits associated with colon cancer -- weighed more
heavily than diet in men's risk of the disease. The American Cancer Society recommends that people exercise regularly
and follow a diet rich in fruits, vegetables and whole grains as one way to
lower the risk of colon cancer.
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Study advises cutting back on
red meat: Heavy doses can add to risk of colon cancer -(Yahoo
News-20/01/2005)
Men who eat a hamburger-sized portion of red meat most days of
the week can have a heightened risk of colon cancer, according to an
American Cancer Society study published this month.
The same risk exists for women who eat red meat two to three times a
week.
The national study of nearly 150,000 adults older than 50 said those who
reported eating the most red meat in a 10-year period were 30 percent
more likely to develop colon cancer than those who reported eating
little or no red meat.
Processed meat increased the risk to 50 percent in those eating at least
1 ounce per day. That's similar to a slice of bologna up to six days a
week for men and three days a week for women.
The risk posed by eating red and processed meat multiple days a week for
10 years, according to the Cancer Society, is slightly less than the
risk factors of physical inactivity and obesity.
"The fortunate side is that some of those factors are within our
control, such as lifestyle and dietary choices," said Liz Swords,
director of clinical research at the Cancer Care Institute in Decatur.
"For instance, populations that have diets high in fat, protein, high
calories, alcohol and low folate are more likely to develop colorectal
cancer than those populations that are low in fat but high in fiber,
fruits and vegetables."
Other choices that can help decrease the
risk of colorectal cancer include quitting smoking and avoiding diets
high in saturated fats combined with sedentary lifestyles.
Yet, Swords added, avoiding the controllable risk factors does not
guarantee immunity.
Colorectal cancer was the second leading cause of cancer death in
Illinois between 1996 and 2000, according to the Illinois Department of
Public Health. It was the third most commonly diagnosed in Illinois
during that period.
The Cancer Society described colon cancer and rectal cancer as similar,
developing slowly over several years. The five-year survival rate is as
high as 90 percent for those who catch the cancer in its early stages,
such as through colorectal screenings.
However, only 37 percent of colorectal cancers are found at the early
stage, according to the American Cancer Society's Illinois Cancer Facts
and Figures 2004.
Screenings should begin at age 50 and include fecal occult blood test
every year, flexible sigmoidoscopy every five years, double-contrast
barium enema every five years and colonoscopy every 10 years.
Laura Sechrest, director of St. Mary's Hospital Food and Nutrition
Services, said there are ways to reduce the risk of colorectal cancer
without cutting out red meat or animal fat completely:
*Limit meat intake and eat low-fat meats, such as eye round, top round,
round tip, top sirloin, bottom round, top loin, tenderloin and flank.
*For processed meats, limit bacon, hot dogs and luncheon meats or buy
the 95 percent fat-free versions.
*Use cooking methods that limit or eliminate extra fat: broiling,
grilling, roasting, stewing, steaming and stir-fry.
* Use nonstick pans or a thin coat of vegetable oil spray.
* Trim all visible fat before cooking.
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Calcium Cuts Women's Colorectal Cancer Risk -Study-(Reuters-20/01/2005)
Diets rich in calcium reduce women's risk of
colorectal cancer, and women who also take calcium supplements can cut their
risk even more, researchers said. The protective effect of calcium likely works in men as well as women,
though dairy products rich in calcium are also known to heighten the risk of
prostate cancer, doctors from the University of Minnesota Cancer Center
said. Roughly 150,000 people in the United States are diagnosed with colorectal
cancer annually, and it ranks second to lung cancer as the leading cause of
cancer death, the report published in the journal Cancer Epidemiology,
Biomarkers and Prevention said.
Of the more than 45,000 cancer-free women surveyed at the start of the
study, 482 developed colorectal cancer after being tracked for an average of
8.5 years. Those who consumed at least 800 milligrams of calcium daily had a 26
percent lower risk of the disease compared to women who consumed less than
530 milligrams. Women who consumed more than 412 milligrams of calcium from dietary
sources and also took more than 800 milligrams in supplement form had a 46
percent lower risk. The U.S. government recommends a daily calcium allowance of 1,200
milligrams.
"Risk reduction was present regardless of the source of the calcium,"
said study author Andrew Flood. "It was the calcium per se, and not merely
dairy products or some other variable that accounted for the reduction in
risk." One theory holds that calcium neutralizes bile acids produced during the
digestion of fat that can irritate the cells lining the colon, he said. Or,
calcium might act on the cells' biochemical pathways that regulate how they
grow and mature, and determine whether the cells become cancerous.
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Selenium
May Reduce Colon Cancer Risk-(HealthDayNews-16/11/2004)
High levels of selenium in the blood may
reduce the risk of colorectal cancer, according to a new study that
suggests but doesn't prove the mineral's role as a preventive. Selenium is
a trace mineral found in meats, grains, seafood and some nuts. However,
how much you get varies according to where you live, because different
areas have different concentrations of selenium in the soil. Those who
live in areas where selenium intake is low have higher rates of colorectal
and other cancers. "Your risk of colorectal cancer can vary by the
amount of selenium you consume," said lead researcher Elizabeth T.
Jacobs, from the Arizona Cancer Center. "People with higher blood
selenium levels tended to have a decreased risk of a recurrence of colon
cancer." Selenium may protect against not only colon cancer but also
prostate cancer and lung cancer, Jacobs added.
Jacobs and her colleagues collected data
from three randomized trials of colon cancer patients: the Wheat Bran
Fiber Trial, the Polyp Prevention Trial and the Polyp Prevention Study.
Looking at the data from these trials, they were able to determine the
effect of selenium in the development of new cancerous colon polyps in
patients. The researchers found that those with the highest selenium
levels had a 34 percent lower risk of developing a new colon cancer,
compared with those who had the lowest selenium levels. Their report
appears in the Nov. 17 issue of the Journal of the National Cancer
Institute. Whether increasing your selenium intake will actually be
beneficial is not clear. Jacobs said that increasing selenium consumption
will help people who have low levels of the element. "It will benefit
those whose intake of selenium is low," she said. "However, it
may not benefit those who already have adequate selenium levels."
The risks of having too much selenium are
not known but are being studied, Jacobs said. In addition, studies are
under way to determine the optimum selenium levels needed to prevent colon
cancer and prostate cancer. Jacobs also said there are ongoing studies to
see if selenium can help treat patients with prostate cancer.
"Selenium is a promising preventive agent for colorectal cancer, but
we are hopefully going to confirm this," Jacobs said.
"This study is not definitive,"
said Dr. Scott M. Lippman, chairman of the department of clinical cancer
prevention at the University of Texas M.D. Anderson Cancer Center,
"because it is not from a large randomized control trial of
selenium." Based on this study, Lippman believes that such trials
should be done to test the benefit of selenium in preventing colon cancer.
Data from ongoing trials may provide an answer, he said: "I believe
that over the next five to 10 years, we will have some very compelling
data one way or the other regarding selenium's ability to suppress
colorectal cancer." Lippman, who co-wrote an accompanying journal
editorial, said there are biological reasons that may make selenium
effective in preventing colon cancer.
"There is laboratory information that
suggests that selenium might prevent colorectal cancer," he said.
One of these mechanisms is selenium's role in turning on genes that prevent
cancer. Another is the mineral's effect in altering the metabolism of
polyunsaturated fatty acids found in red meats, which are involved in
the development of colorectal cancer, Lippman said. "Not only are
the epidemiological data very consistent and supportive, but there are
actually fairly strong biologic plausibility for selenium's ability to
protect against colorectal cancer," he said. However, Lippman cautioned
that the results of this study do not mean that people should start taking
selenium supplements in the hope of preventing cancers. "The epidemiological
and biological data strongly support going to the next step of a definitive
randomized trial to find out if in fact it does work," he said.
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FDA
Approves Wider Use for Sanofi Cancer Drug-(Reuters-07/11/2004)
Sanofi-Aventis said on Friday
that U.S. regulators have approved wider use for its colon cancer drug
Eloxatin. The drug, currently used to treat patients whose cancer has
spread to other parts of the body, can now be used following surgery and
before the disease has spread, the company said. The
news was expected as Eloxatin has already been approved for wider use in
Europe.
Recently introduced drugs such as Genentech
Inc.'s Avastin and ImClone Inc.'s Erbitux are currently used to treat
patients in the later stages of the disease. Patients
who have recently had surgery are typically treated with standard chemotherapies.
Dr. Sunil Gupta, senior director of clinical
development, oncology at Sanofi-Aventis, said he believes about 40 percent
of colon cancer patients fall within the category that Eloxatin is now
approved for -- post surgery but before the disease has spread to other
organs.
[Back]
Bowel cancer
trials 'offer hope'-(Yahoo News-29/10/2004)
A treatment breakthrough should mean
many more people with bowel cancer can be cured, say experts.When caught
early and treated, there is already a good chance of survival, but in some
patients the cancer can return. In trials, surgery combined with a new mix
of chemotherapy drugs improved the chance of a complete cure by 25%
compared to standard chemotherapy. The
data was presented by its Paris-based author at a European Society for
Medical Oncology meeting in Vienna.
Bowel cancer affects about 38,000 people in
the UK each year - mainly over 60s - killing about 14,000. While it is
obvious that picking up the disease and treating it as early as possible
is the best way to ensure a cure, the success rates have not been high
enough. Dr Rob Glynne-Jones, Macmillan lead clinician at the Mount Vernon
Cancer Centre in Middlesex, said: "This is the first time for years
that we have had a major advance where patients are actually going to be
cured." He said for about 50 years there had been only one
chemotherapy treatment available to treat bowel cancer, which was based on
a drug called 5-FU. Giving this treatment after surgery to remove the
tumour reduces the risk of the cancer coming back by about 30%, he said.
In the trials on 2,246 patients with colon cancer, adding another drug,
called oxaliplatin, reduced the risk by a further 25%.
Dr Glynne-Jones explained: "I know
that may not sound very much, but when you think there are 38,000 patients
getting colon cancer a year and probably 10 or 15,000 of them having
chemotherapy afterwards, you are going to save quite a lot of lives.
"For the 30% of those who would have relapsed you are going to reduce
that by a quarter. That's quite a big issue," he said. He
said adding in the extra drug did make the chemotherapy side-effects
worse, but he said patients tended to accept that as a trade off for the
increased likelihood of a cure. In particular, the treatment can cause
numbness or tingling in hands by affecting the nerve endings.
Oxaliplatin chemotherapy is available in
some places in the UK. The National Institute for Clinical Excellence is
looking at its availability and is expected to make recommendations in May
2006. The patients in the study all had stage three bowel cancer, which
means the tumour is confined to the bowel and has not spread. Author of
the research, Dr Aimery de Gramont, from the St Antoine Hospital in Paris,
told the Vienna conference the findings confirmed the importance of
treating early with chemotherapy and surgery.
Jola Gore-Booth, chief executive
of Colon Cancer Concern, said: "Lack of awareness is one of the main
reasons colon cancer remains a killer. "There is still considerable
lack of knowledge and embarrassment surrounding this condition, which
means that many people do not recognise the symptoms or do not act upon
them. "We need to get across
the message that colon cancer is curable if caught through early diagnosis
and treated appropriately, and encourage patients to act upon their symptoms
as early as possible."
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Doctors
Advise Chemo Before Rectal Cancer Surgery-(Reuter News- 20/10/2004)
Administering
chemotherapy and radiation before surgery for rectal cancer may not help
patients live longer, but it produces fewer side effects than when it is
given afterward, doctors reported on Wednesday. The new finding, published
in The New England Journal of Medicine, could translate into less
suffering for people with rectal cancer, which affects about 42,000 people
in the U.S. each year. Traditionally, doctors have performed surgery
first. "Preoperative chemoradiotherapy is the preferred treatment for
patients with locally advanced rectal cancer," said a team led by
Rolf Sauer of the University of Erlangen in Germany. Giving chemotherapy
and radiation first may make chemotherapy more tolerable and may shrink
the tumor, making it easier to remove with less damage to the rest of the
body, they said.
Nearly 800 volunteers and doctors in 26
hospitals were involved in the test, which followed each patient for an
average of four years. The Sauer team found that the five-year survival
rate was about 75 percent, whether or not surgery was done first. The rate
of complications during surgery was about 35 percent in each group. But
far more people who had their surgery first suffered from side effects
when they eventually received their radiation and chemotherapy. The rate
of short-term side effects such as diarrhea was 40 percent among patients
who got surgery first, versus 27 percent for those who got it after drug
and radiation treatment. Having surgery after chemoradiation cut the risk
of long-term side effects nearly in half. In an editorial in the Journal,
Robert Madoff of the University of Minnesota in Minneapolis said the Sauer
team has provided "convincing evidence" that it's better to have
surgery last with that type of cancer. He said evidence has been steadily
accumulating from other studies supporting the conclusion of the Sauer
group.
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Obese
Men More Prone to Colon Cancer-(Yahoo News-18/08/2004)
Obese adult men are more prone
to colon cancer, according to research conducted by a university team.
Assistance professor Kim Chang-sup of Ulsan University Medical School on
Friday released the results of research on 618 adult men in their 40s-70s
conducted for two months last year. Kim discovered that obese men have a
higher risk of developing large intestine polyps, which may develop into
cancer. The finding is the first of its
kind to show a close link between obesity and colon cancer.
Kim's research team divided the
participants into one obese and two normal groups for the study. According
to the research on all three groups, 142 adults or 23 percent were found
to have lower polyps in the colon, while 99 men or 16 percent had
adenomatous polyps, which are more likely to develop into colon cancer.
However, in the obese group, 32.7 percent were found to have large
intestine polyps, while only 18.6 percent of the first normal group and
17.7 percent of the second normal group tested positive for them. Obese
men also turned out to have a higher chance of having adenomatous polyps
with 22.5 percent while 15.3 percent of the first normal group and 14.4
percent of the second group tested positive.
The research reported that
those who smoke heavily and are older or particularly obese around their
waist and hips have higher chances of having large intestine polyps.
``Colon cancer is quite prevalent, ranking fourth among all the cancers as
the main killer in terms of fatality and occurrence rates,¡¯¡¯ Kim
said, adding that adults should stay in shape because obesity is closely
related to the occurrence of large intestine polyps.
[Back]
Clue
to 'blocking' bowel cancer-(Yahoo News-18/08/2004)
The
removal of a cell "switch" in mice stopped growth of lesions in
the bowel that can turn cancerous with time. The Vanderbilt University
team hopes a drug that blocks this switch, which has been developed in
France, could have the same effect in humans. The scientists told Cancer
Cell journal they planned to test this drug in mice. Cancer Research UK
said it was a long way from human therapy.
Cells have receptors that can be turned on and off to control different
processes in the body.
A
receptor called PPARdelta is thought to be important for the development
of tag-like lesions of bowel tissue called polyps. Bowel polyps are
generally harmless but can become cancerous with time, leading to
full-blown bowel cancer. A hormone-like substance called prostaglandin E2
(PGE2) has also been linked to the development of polyps and bowel cancer.
Dr Raymond DuBois and colleagues investigated the relationship of these
receptors and substances in mice. They bred mice with a certain genetic
mutation that made them prone to developing polyps in the bowel. When
these mice were exposed to PGE2 they had many more polyps than they
normally would have. The scientists then mated these mice with mice that
lacked a gene for PPARdelta. The offspring would then be able to develop
polyps but these polyps would not contain any PPARdelta receptor, they
reasoned. When these mice were exposed to PGE2 they had the usual number
of polyps. This shows PPARdelta is important for PGE2 to encourage polyp
growth and, therefore, cancer growth, according to the scientists.
"Now we can really focus on key components," said Dr DuBois.
His
team plan to test a French drug that has the same effect as knocking out
the gene for PPARdelta. This work will begin in mice. Dr Elaine Vickers,
science information officer at Cancer Research UK, said: "Several
scientific studies have suggested a role for PPARdelta in the development
of polyps in the bowel. "This work has increased the evidence that
PPARdelta is important in polyp formation. But this research is still at
an early stage, and there is a long way to go before this work could be
applied to humans."
Colon
Cancer Concern welcomed the study and said it would be important for
people who are prone to bowel cancer. A spokeswoman said: "Genetic or
familial cancers are particularly challenging and require as much research
as possible to improve the long term survival for these specific
patients."
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Cancer
Drug Warning Won't Change Its Use--(HealthDayNews-16/08/2004)
Government advisory that
colorectal cancer drug Avastin had adverse side effects was based on
updated trial data. Last week's warning that the colorectal cancer drug
Avastin has life-threatening side effects seems unlikely to change its
application, experts say. "We will continue to use the drug,"
said Dr. Peter Kozuch, an attending physician at St. Luke's-Roosevelt
Hospital and Continuum Cancer Centers of New York in New York City.
"It represents an important option in the treatment of metastatic
colorectal cancer."
The U.S. Food and Drug
Administration approved the drug in February to treat colorectal cancer
that had spread to other parts of the body. According to product
information, Avastin is a monoclonal antibody that cuts off blood supply
to cancer cells. In pre-approval studies, researchers found Avastin, in
combination with chemotherapy, gave patients an extra five months of life.
But last week, the FDA and Avastin's manufacturer, Genentech Inc., alerted
health-care providers that the drug carried with it a heightened risk of
blood clots, which can lead to stroke, heart attack and chest pain. The
warning letter to doctors, to be followed by new drug labeling, said the
risk of serious heart problems was doubled for cancer patients who took
Avastin with their chemotherapy.
In the research on which the
approval was based, a small number of such "events" was noted,
Dr. David Ross, deputy director of the FDA's Office for Drug Evaluation 6,
said. Recently, newer study data showed that, in a trial of 200 people, 10
of those on Avastin (5 percent) had an adverse effect, compared to five in
a control group. Ross noted, however, that the newer group of people was
older and more frail than those in the initial study. But, he added,
"The company's analysis of the data and the FDA's analysis, which is
ongoing, is that there is enough data to update the labeling and focus on
arterial [heart attacks and strokes] versus venous events. This is
important information for providers to have."
"There were a small number
of cases before, and now a small number of cases in a different patient
population," added FDA spokesman Jason Brodsky. "Taken together,
the prudent thing to do was to issue a warning and follow up with labeling
revisions to reflect the new information."
Because labels take time to
update and distribute, Genentech sent a letter to health-care providers on
Aug. 12. As the first monoclonal antibody approved for this type of
cancer, Avastin is, in a way, a breakthrough drug. It is considered a
"biologic" drug, meaning it's more targeted than previous
generations of drugs. Still, Avastin is only approved for use in
combination with traditional chemotherapy. It is still not proven that the
side effects seen are related to the drug or represent a statistical
anomaly, Kozuch pointed out. Regardless, any decision to use Avastin will
clearly have to consider both risks and benefits. "Avastin is
indicated for a life-threatening disease, but these side effects are also
life-threatening," Ross said. "The challenge is to individualize
the decision for a particular patient."
Colon cancer is the third most
common cancer among men and women in the United States, according to the
American Cancer Society. ACS estimates say there will be 106,370 new cases
in 2004. Kozuch said, however, that even though colorectal cancer is
extremely grave, there are patients who are asymptomatic. And the new
warning may need to be addressed. "They may have many months of good
quality of life left and we would hate to diminish that for something
catastrophic like a stroke," he said. "This is not a matter of
killing the horse twice. We
will have to have very careful discussions with patients regarding chest
pain, heart attack and stroke," he added. "In patients who have
recently had a heart attack or stroke, they may not want to take this drug
at all."
[Back]
Researchers
locate gene that promotes cancer growth-(Japan Times-06/07/2004)
A university research group has discovered
a particular gene that frequently leads to malignant tumors in the colon,
rectum or liver, possibly paving the way for the development of a new
treatment. Cancer can stem from genetic abnormalities and the gene
involved in the proliferation of cancer cells--SMYD3--could provide
researchers with valuable information. The discovery was made by a
research group led by Prof. Yusuke Nakamura and assistant researcher Ryuji
Hamamoto at the Institute of Medical Science at Tokyo University and was
reported Sunday in the online edition of the British journal Nature Cell
Biology.
According to the researchers, SMYD3 is a
class of enzyme called methyltransferase. Their study suggests that the
gene contributes to the proliferation of cancer cells through its
interaction with the oncogenes, homeobox genes and other genes associated
with cell-cycle regulation. The study found that SMYD3 enhanced cell
growth and was a contributing factor in increasing not only ordinary
cell-growth, but that of cancer cells as well. But the researchers
confirmed the effects of SMYD3 on colorectal and liver cancer could be
significant suppressed and believe that SMYD3 is one of the main enzymes
that trigger extraordinary cell growth.
According to statistics compiled by the
Health, Labor and Welfare Ministry in 2003, cancer was the main cause of
death in the country, while colorectal cancer ranked fourth as the cause
of death for men and top for women. Liver cancer ranked third among men
and ranked fourth for women. "It (the study) may be instrumental in
curing colorectal and hepatocellular cancer," Nakamura said.
[Back]
Milk
May Lower Risk of Colorectal Cancer-(Yahoo News-06/07/2004)
Drinking at
least a glass of milk a day may lower the risk of colorectal cancer,
say researchers who pooled some of the world's largest studies on the
long-believed link. Calcium, from milk or other sources, has long been
thought to play a role in preventing colorectal cancer, the nation's
second-leading cancer killer. Studies show high calcium intake reduces the
occurrence of polyps that can turn cancerous. But diet-tracking studies
stopped short of finding final proof of a truly lowered cancer risk.
To better define
that link, scientists at Boston's Brigham and Women's Hospital analyzed 10
studies that together tracked nutrient consumption of more than half a
million people, nearly 5,000 of whom eventually got colorectal cancer.
People who consumed 6 to 8 ounces of milk a day had a 12 percent lower
risk of later developing colorectal cancer than those who drank less than
two glasses a week, the researchers report in the Journal of the National
Cancer Institute. With more than a glass a day, the risk reduction was 15
percent. Other dairy foods didn't show a statistically significant
relationship.
A total calcium
intake — from diet plus calcium supplements — of 1,000 milligrams a
day was protective, too. The researchers calculated that if all study
participants had consumed that much, the women may have suffered 15
percent fewer cases of colorectal cancer and the men 10 percent fewer.
Vitamin D, commonly added to milk, also is thought to play a role, either
alone or because it helps the body absorb calcium. The study couldn't
tease out vitamin D's role, but found the biggest protective effect with
the highest doses of both nutrients.
Health Tip: Eat
Grilled Meat Only Occasionally
Despite their
luscious taste, grilled meats should only be eaten occasionally, according
to the American Institute for Cancer Research. This is because grilling
and other high-heat cooking methods can produce compounds on meat and fish
that are suspected of causing cancer. There are other foods that make
great grilling options and don't form the compounds, says the University
of Texas Health Science Center. Vegetables, such as corn, asparagus,
squash, and broccoli, are great on the barbeque, as are some fruits. Brush
fruit and veggies with a little olive oil and grill them over medium heat,
the institute suggests.
[Back]
Combination
of CAMPTOSAR(r) (Irinotecan HCL Injection) and AVASTIN(tm) (Bevacizumab)
Shows Survival Benefit in First-Line Treatment of Advanced Colorectal
Cancer-(AScribe Newswire- 28/06/2004)
Data
presented today at the annual meeting of the American Society of Clinical
Oncology (ASCO) showed that first-line therapy with a combination of
CAMPTOSAR (irinotecan HCL injection) plus bolus 5-flouruocil/leucovrin
(5-FU/LV) (IFL) and Avastin (bevacizumab) prolongs survival in patients
with metastatic colorectal cancer (MCRC) when compared with a standard
first-line MCRC therapy. In a separate report, data from a trial of
combination therapy of Erbitux (cetuximab) and CAMPTOSAR plus infusional
5-FU/LV (FOLFIRI) showed the combination to be generally safe and
well-tolerated, and active as a first-line MCRC treatment. "The
body of scientific evidence demonstrating the safety and efficacy of
CAMPTOSAR combinations with select targeted agents continues to
grow," said Paulo Hoff, MD, associate professor in the Department of
Gastrointestinal Medical Oncology at the University of Texas, M. D.
Anderson Cancer Center in Houston. "The survival advantage of
CAMPTOSAR combinations in the treatment of MCRC seems to be further
improved when coupled with these promising targeted therapies, making
CAMPTOSAR-containing regimens one of the preferred choices for treatment
and an excellent candidate for further clinical research."
Data from patients enrolled in a Phase III
trial that compared the survival impact of IFL plus Avastin therapy with
IFL plus placebo therapy in the first-line treatment of MCRC, who
continued to be monitored throughout post-progression therapy (PPT),
showed that patients who received first-line treatment with Avastin and
IFL, followed by second-line treatment with an oxaliplatin-containing
regimen, lived an average of 25.1 months compared with patients who
received first-line IFL plus placebo therapy and second-line treatment
with a non-oxaliplatin regimen who lived an average of 15.8 months. In
separate subgroup analysis, researchers found the first-line survival
benefit observed with IFL plus Avastin therapy was present among all
pre-defined subgroups with the largest increases in survival noted among
patients with rectal cancer and among male subjects.
"It appears from the post-progression
analysis that the sequencing of therapeutic regimens may play an important
role in further extending survival in advanced colorectal cancer
patients," said S. Hariharan, MD, Medical Director at Pfizer
Oncology. "The survival data showing an average survival of 25.1
months is the highest we have seen with any sequence of first- and
second-line therapies in MCRC."
In another first-line therapy study,
preliminary results from a Phase II trial of combination therapy with
Erbitux plus CAMPTOSAR and infusional 5-FU/LV (FOLFIRI) in the treatment
of EGFR-expressing MCRC indicate the combination is effective, with 10
patients (46 percent) achieving partial response and 9 patients (41
percent) achieving stable disease. Safety analysis from additional
patients (enrolled later) show the regimen to be well-tolerated.
"CAMPTOSAR is currently being studied
in more combinations with targeted therapies than any other chemotherapy
agent," added Dr. Hariharan. "With the proven survival advantage
of CAMPTOSAR at their core, these new combinations have already increased
survival for patients with advanced colorectal cancer beyond what was
thought possible only a few years ago and with continued research may one
day transform advanced cancers from deadly killers to manageable
diseases."
About the Avastin + IFL Trial (No. 3517)
The randomized Phase III trial (AVF2107)
evaluated the safety and efficacy of a combination regimen of Avastin plus
CAMPTOSAR and 5-FU/leucovorin (using the bolus IFL regimen) as a
first-line treatment for patients with MCRC compared with IFL plus
placebo. Interim results from this study were used to support the recent
FDA approval of Avastin for use in the first-line treatment of MCRC after
demonstrating that the combination provides significant improvement in
survival (20.34 months) compared with IFL alone (15.61 months)
(p=0.00004). Patients from the trial also were monitored for survival
based on their first-line therapy (IFL + Avastin or IFL + placebo) and
whether they received second-line therapy with a regimen containing
oxaliplatin.
815 patients were enrolled in two treatment
arms for first-line treatment (IFL/Avastin or IFL/placebo). Following
disease progression, patients who continued on in the study were divided
based on their first-line therapy (IFL + Avastin or IFL + placebo) and
their second-line therapy (oxaliplatin, no-oxaliplatin) resulting 4
groups: IFL + placebo and non-oxaliplatin group (122 patients); IFL +
placebo and oxaliplatin group (109 patients); IFL + Avastin and non-oxaliplatin
group (125 patients); IFL + Avastin and oxaliplatin group (97 patients).
Following first-line treatment, patients who received IFL + Avastin had an
overall progression free survival of 10.6 months compared with 6.2 months
for IFL alone (p<0.00001). Patients in both treatment arms who received
second-line treatment with oxaliplatin had higher overall survival than
patients who received the same first-line therapy (IFL + Avastin: non-ox
19.6 months, ox 25.1 months (p<0.05): IFL: non-ox 15.8 months, ox 22.2
(p<0.01). The highest overall survival, 25.1 months, was achieved by
patients, who received first-line therapy with IFL + Avastin and
second-line treatment with an oxaliplatin containing regimen.
About the Erbitux Trial (No. 3513)
The Phase II study evaluated the safety and
efficacy of combination therapy with Erbitux plus CAMPTOSAR, and 5-FU/LV
administered via the FOLFIRI regimen in the first-line treatment of EGFR-expressing
MCRC. All patients received a 400 mg/m2
initial dose of Erbitux and 250 mg/m2 Erbitux weekly for the remainder of
the study period. Patients were divided into two treatment arms and
received either low-dose FOLFIRI (LD) (180 mg/m2 CAMPTOSAR plus 400 mg/m2
leucovorin (bolus) and 300 mg/m2 5-FU (bolus) followed by 2,000 mg/m2 5-FU
(via 46-hour infusion)) or high-dose FOLFIRI (HD) (180 mg/m2 CAMPTOSAR
plus 400 mg/m2 leucovorin (bolus) and 300 mg/m2 5-FU (bolus) followed by
2,400 mg/m2 5-FU (via 46-hour infusion)) therapy every two weeks.
The study initially enrolled 10 patients in
the LD group and 13 patients in the HD group, who were monitored for
dose-limiting toxicities (DLTs), response, and time-to-tumor progression (TTP),
and adverse events. Following a low incidence of DLTs in both groups, the
HD group was expanded to include an additional 29 patients. No DLTs were
observed in the LD arm and 3 DLTs were reported in the HD arm (grade 3
diarrhea, grade 3 allergy, grade 4 neutropenia).
Among the initial 23 patients enrolled, 22
were evaluable for efficacy. Ten patients (46 percent) achieved partial
response, 9 (41 percent) achieved stable disease, 3 (14 percent) had
progressive disease. Median TTP stands at 10.9 months. Additional safety
analysis from the 42 patients in the HD arm show the most frequent grade
3-4 adverse events to be diarrhea (14.3 percent), neutropenia (11.9
percent), rash (11.9 percent), and nausea/vomiting (9.5 percent).
About CAMPTOSAR(r) (irinotecan
hydrochloride injection)
CAMPTOSAR(r) is approved in combination
with 5-fluorouracil/leucovorin (5-FU/LV) as initial, or first-line,
therapy for the treatment of advanced (metastatic) colorectal cancer. The
combination shown to increase survival in multiple studies has
demonstrated consistent success in first-line treatment in objective tumor
response rates and time to tumor progression. CAMPTOSAR is also a central
component of combination therapy playing a primary role in the studies
that supported the FDA approvals of molecular targeted agents, Avastin(tm)
and Erbitux(tm).
CAMPTOSAR is associated with neutropenia
and both early and late forms of diarrhea, which can be life threatening
if not managed properly. Full prescribing and safety information,
including black box warning, can be found at http://www.pfizeroncology.com/camptosar
[Back]
Calcium
More Protective Against Some Polyps-(Yahoo
News-15/06/2004)
High-Fiber,
Low-Fat Diet Helps Calcium Prevent Colon Cancer.
Calcium supplements could cut colon polyp risk -- especially advanced
polyps that lead to colon cancer, new research suggests. The
report appears in the latest issue of the Journal of the National
Cancer Institute. "Our results suggest that calcium
supplementation may have a more pronounced ... effect on advanced [colon
polyps] than on other types of polyps," writes lead researcher
Kristin Wallace, MS, with Dartmouth Medical School in Lebanon, N.H.
While some research has looked at this
link, few have addressed it in any detail -- to look for the effects of
calcium on different types of colon polyps, Wallace explains. These
studies make no distinction on the effects of calcium supplements on polyp
size or other characteristics. Also, what are the effects of calcium in
the diet and from pills? One study has suggested that a 700 mg supplement
daily may prevent polyps. However, it's not been clear whether a
high-calcium diet boosts or hinders that effect, she writes.
The researchers analyzed data from patients
involved in the large Calcium Polyp Prevention Study. The analysis
involved 913 patients whose average age was 61 and who were followed for
at least four years. They had been randomly assigned to take either 1,200
mg calcium supplements or a placebo. Each volunteer was asked about the
calcium, fat, and fiber they typically got in their diet. Each participant
had a history of having a polyp removed at least three years prior to the
start of the study. They also had a colonoscopy at the beginning of the
study to document no remaining polyps in the colon.
After four years
the calcium group had 18% fewer noncancerous polyps and 35% fewer advanced
polyps -- those with features that have a higher potential to become
colorectal cancer -- compared with the placebo group.
There was another interesting pattern:
Those with fewest polyps ate a high-calcium, high-fiber, low-fat diet.
However, the numbers did not tally up as a definitive finding, notes
Wallace. In all, her study suggests that total calcium intake over 1,200
mg daily is necessary for colon protection -- and that a high-fiber diet
with modest levels of fat will boost the protective effects, she writes.
Wallace's findings are in line with similar
studies but fall short of proving a preventive link between calcium, colon
polyps, and colon cancer, writes Arthur Schatzkin, PhD, with the National
Cancer Institute, in an editorial. However, studies are in place that
could prove that this one nutritional factor -- calcium -- could offer
protection against colon cancer. "That would be a tremendous
advance," writes Schatzkin.
It's not clear how calcium acts to reduce
colon polyps, writes Wallace. It may be that calcium binds
"irritants" like bile acids and other fats in the bowel that are
carcinogenic -- acting as a sort of "soap," possibly preventing
colon cancer.
[Back]
Diseases
share common lifestyle factors, study suggests-(Yahoo News-12/06/2004)
Diabetics
may have three times the normal risk of developing colorectal cancer,
researchers said. They found that a marker for raised sugar levels in
blood samples could be an indicator of people more likely to develop the
cancer that kills more than 490,000 people each year.
In
a study of 10,000 people, those with the highest blood sugar levels, even
if they were below amounts diagnosed for diabetes, were more likely six
years later to have bowel cancer. “Raised levels of blood glucose, even
in the absence of diabetes, is still associated with an increased risk of
colorectal cancer,” Professor Kay-Tee Khaw, of the University of
Cambridge in England, said in an interview. She and her colleagues are not
suggesting that diabetes, which affects 194 million people worldwide,
causes colorectal cancer but that it may be a marker for something else
that increases the risk. “We think the interpretation of this is that
there are common lifestyle factors that appear to predispose to both
diabetes and to colorectal cancer, such as diet or physical activity,”
Khaw said.
People
can have raised glucose levels without having diabetes but those with the
highest levels are considered to be diabetic. “Even
levels below those (of diabetics) seem to be associated with increases in
colorectal cancer,” she added. The research, which was published in the
journal Cancer Epidemiology and Biomarkers, was part of the European
Prospective Investigation into Cancer study and looked into whether
abnormal glucose metabolism increases the risk of bowel cancer.
Participants
in the study filled in questionnaires about their health and lifestyle and
blood samples were taken and analyzed. Six years later they were followed
up and 67 had developed bowel cancer. The
people who had the most raised blood sugar levels had the highest rates of
colorectal cancer -- or about three times the risk of people with the
lowest blood sugar levels. Dietary
changes, losing weight and physical exercise can reduce blood glucose
levels, Khaw said.
“This
is giving us some clues as to what the causes of colorectal cancer might
be, particularly the lifestyle factors. Diabetes and colorectal cancer may
share common lifestyle causes,” she said. “If we can identify what
these factors are, then we can slow down the growth of tumors. It (the
research) is providing potential in terms of identifying future treatments
and potential for screening.” But she stressed that it was a small study
and that the findings must be replicated in larger research projects.
[Back]
Drugs
Improve Outlook for Colon Cancer Patients-(HealthDay News-02/06/2004)
Two new drugs improve the outlook for patients with very different
cases of colorectal cancer, researchers in the United States and Europe
report. One prolongs life in advanced cases,
and the other prevents recurrence, new research says. One drug
buys some precious extra months of life when the cancer has spread throughout
the body. The other provides a significant increase in the rate of disease-free
survival when the cancer is detected early enough to be removed surgically.
The one thing both treatments have in common is that each drug is added
to the standard regimen for cancer of the colon and rectum -- a combination
of fluorouracil and leucovorin, say separate reports in the June 3 issue
of the New England Journal of Medicine.
The American trial probably will get most
public attention, since the drug it used, bevacizumab, has been widely
acclaimed as the first example of a unique attack against cancer proposed
years ago by Dr. Judah Folkman of Harvard University. That process is
called antiangiogenesis, which tries to stop the growth of new blood
vessels that a cancer needs to flourish. The study covered just one use of
the drug, for patients whose cancers have spread so much that surgery is
not possible. Their survival time usually is measured in months. "Our
study demonstrated several things," said study author Dr. Herbert I.
Hurwitz, an associate professor of medicine at Duke University. "The
first is that the addition of bevacizumab to first-line therapy conferred
a significant benefit in terms of survival, tumor control and tumor
shrinkage."
The study also appears to provide "the
first blue-chip data set to validate the antiangiogenesis
hypothesis," Hurwitz said. But he leaves open the possibility that
the drug might act in a different way. The 402 patients who were given
bevacizumab in addition to other cancer drugs survived for an average of
20.3 months, compared to 15.6 months for those who got the standard
regimen. "We hope that the validation of the drug's value with one
target can be expanded to provide better benefits against other
targets," Hurwitz said. A number of studies using the drug, whose
brand name is Avastin, have already begun, he said.
In the European study, the rate of
disease-free survival for patients who got a different new agent,
oxaliplatin, in addition to standard therapy after surgery was 78.2
percent after three years, compared to 72.9 percent for those who got only
the standard regimen, said a report by a group led by Dr. Aimery de
Gramont of the Hospital San Antoine in Paris.
The improvement is statistically
significant, said Dr. Robert J. Mayer, director of the center for
gastrointestinal oncology at the Dana-Farber Cancer Institute in Boston.
He grumbled somewhat about the failure of the European researchers to
provide data on survival for more than the three years covered in the
report, but said he stood by the title of an editorial he wrote in the
same issue: "Two Steps Forward in the Treatment of Colorectal
Cancer." Mayer urged caution about Avastin, noting there has been
"a great deal of publicity about this molecule. Many patients come to
me with the understanding that it is a cure. We need to be clear in
exactly what settings it should be used."
Given the need for carefully controlled
trials, progress is inevitably slow, Hurwitz said, but it is being made.
"In
2004, we have seen approval of three drugs for colorectal cancer," he
said. "If this pace of progress continues, then we will be doing very
well."
[Back]
Women's
Preference for Women Physicians is a Barrier to Colorectal Cancer Screening-(AACR
Annual Meeting)
Female
patients tend to prefer seeing female physicians in most specialties of
medicine. A study presented by researchers at the University of Michigan
found that for colorectal screenings in particular, women patients' preference
for a female health care professional is strong enough to delay the procedure
and incur additional expenses, as there is a lack of available female
endoscopists. To confirm their hypothesis, researchers administered a
questionnaire to a prospective cohort of 202 female patients between the
ages of 40 and 70 at four primary care offices.Forty-three
percent of the respondents preferred a female endoscopist. Of those, 87
percent were willing to wait more than 30 days for the female and 14 percent
were willing to pay additional costs for one. Five percent of respondents
said they would not undergo the procedure unless guaranteed a female endoscopist.
Analysis
of the questionnaires showed that the preference for a female endoscopist
was most often predicted by the gender of the primary care physician,
younger patient age and employment status. The sole independent factor
associated with adherence to screening was doctor recommendation. Other
barriers to the colonoscopy procedure included dislike of preparation
and test (31%) and discomfort (18%). "Colorectal cancer can be treated
and lives can be saved if the disease is caught early," according to Stacy
Menees, M.D., lead author of the study. "The preferred screening method
for identifying colorectal cancer is colonoscopy. Our research shows that
seventy-five percent of women report embarrassment as a reason for female
gender preference and in five percent of women, not guaranteeing a female
endoscopist at the time of a colonoscopy is an absolute barrier to having
the procedure performed. Interventions to improve adherence to colorectal
screening must address gender preference with women patients."
[Back]
Diabetes
Mellitus is a Risk Factor for Colon Cancer: A Case Control Study -(AACR
Annual Meeting)
Researchers
at the Overton Brooks VA Medical Center in Louisiana have found a strong
association between diabetes and the risk of developing colon cancer,
according to a conclusive study of more than 50,000 US veterans. In the
retrospective, cross-sectional, case-control study, researchers evaluated
the medical records of 60,697 patients between October of 1998 and June
2003 using regression analysis and adjusting for obesity, smoking, use
of aspirin and alcohol. The 17.7 percent of patients in the study who
had diabetes (8,974 patients) were 32 percent more likely to develop colon
cancer than patients without diabetes.
"Given
the increasing prevalence of diabetes and the serious mortality associated
with colon cancer, we cannot ignore the strong possibility that the two
diseases are related in some way and hope to confirm this theory with
further study," said Rambabu Chalasani, M.D., lead author of the study.
"However, our results should be viewed with caution due to the limitations
of a case-control study and the population in the database." Duration
and degree of control of diabetes was not factored into the analysis and
some factors known to increase the risk of colon cancer, such as family
history of colon cancer and personal history of inflammatory bowel disease
were not incorporated.
However,
their effects were limited by the large size of the patient population.
The incidence of insulin resistance is rising in the US and colon cancer
remains the second leading cause of cancer death. The geographic patterns
of the two diseases are extremely similar; both were considered relatively
rare before industrialization and the incidence has increased in regions
undergoing economic development. Insulin resistance has been associated
with hyperinsulinemia, increased levels of growth factors and alterations
in receptor signaling, which may promote colon cancer.
[Back]
Screening
Can Cut Bowel Cancer Deaths-Scientist-(Reuters-18/05/2004)
A
national screening program in Britain to detect bowel cancer could save
lives but the government must make sure there are enough trained staff
to ensure it runs efficiently, a cancer expert said. "Over the past 15
years dramatic reductions in incidence rates of bowel cancer in the United
States have been attributed to screening," Dr Wendy Atkin, of St Mark's
Hospital in London, told a science conference. "During the same period
in the UK incidence rates have remained unchanged in women and have even
increased in men." Bowel cancer is now the second highest cause of cancer
death in Britain and the government has been considering introducing a
screening system to detect the disease early when it is most treatable.
A national screening program is expected to be introduced within the next
five years.
Atkin
said she has no doubt that the program will reduce deaths from the disease
but said it is essential that the state-funded National Health Service
(NHS) can cope with it. Britain is considering two screening options for
the program, Atkin told a meeting of the charity Cancer Research UK. One
test will detect hidden blood in the stool, which can be an early sign
of the cancer, and another is a more invasive method, to look for precancerous
growths in the lower part of the bowel. Trained staff to conduct the tests
are in short supply, according to Atkin. She found wide variations in
detection rates in a study in trial centers testing for precancerous growths.
"Making sure that the NHS is ready for the implementation of a bowel screening
program in terms of staffing, resources and access to services should
be a high priority for the government," Atkin told the meeting.
[Back]
Drug
Route Doesn't Affect Colon Cancer Survival-(Reuters Health-18/05/2004)
Chemotherapy
drugs are often given after surgery for colon cancer. New research now
indicates that the route these drugs take in entering the body doesn't
affect survival. Chemotherapy can be injected into veins to deliver the
drugs throughout the body, known as systemic delivery, or into veins that
largely limit delivery to the liver, called intraportal delivery. Doctors
have been unable to reach a consensus regarding which method is best.
The current findings are based on a study of 1,084 patients who underwent
surgery for colon cancer and were randomly selected to receive chemotherapy
delivered systemically, intraportally, or by both routes. The results
are published in the Journal of the National Cancer Institute.
During
a follow-up period of more than 8 years, 389 adverse events, including
recurrences, new cancers, or deaths, were observed, Dr. Roldano Fossati,
from Istituto Mario Negri in Milan, Italy, and colleagues note. A total
of 361 patients died. Despite the different drug routes, the survival
rates for the three groups were similar--about 74 percent, the authors
note. Moreover, the body regions where cancers returned were comparable
in the groups. "To our knowledge, this is the largest study of patients
with colon cancer that has compared the efficacy" of this form of chemotherapy
delivered by these methods, the investigators state. The main finding
is that combining the intraportal and systemic drug delivery methods did
not provide an increase benefit to patients, and that the results were
similar to those seen when the individual routes were used separately.
[Back]
Protein
promotes cancer metastasis and survival-(Yahoo News-19/04/2004)
A
new study demonstrates that a protein called periostin promotes deadly
spreading and late stage progression of colon cancer. The research results
demonstrate that periostin promotes metastatic growth of colon cancer
by activating signaling molecules that encourage cell survival and identify
the protein as a potential therapeutic target for the control of colon
cancer. Colorectal cancer commonly metastasizes to the liver and is the
second leading cause of death from cancer in the United States. As with
most cancers, it is the metastasis and not the primary tumor that is responsible
for cancer fatality. However, the complex mechanisms associated with tumor
metastasis are not very well understood.
Dr.
Xiao-Fan Wang from Duke University Medical Center and colleagues searched
for genes associated with metastatic tumors in samples from primary and
metastatic colon cancers and found that periostin was highly expressed
in metastatic tumors. When periostin was introduced into human colon cancer
cells grown in the laboratory, the cells were much more likely to metastasize
to the liver when subsequently introduced into mice. The researchers went
on to show that the underlying molecular mechanism for periostin-mediated
tumor metastasis is related to an increase in survival of cancer and blood
vessel cells under stressful conditions. The researchers conclude that
periostin plays a critical role in the progression of colon cancers and
may be involved in metastasis of other cancers as well. "Metastasis accounts
for the majority of the mortality associated with colorectal cancer, making
control of metastasis an attractive treatment goal," explains Dr. Wang.
"Our findings identify periostin as a potent promoter of late stage tumor
progression. It is likely that periostin and similar types of proteins
enable tumor cells to thrive in distant organs and grow under conditions
that normally would be inhospitable. Targeting these proteins may prove
to be a highly effective strategy for preventing late-stage progression
of deadly metastatic cancers."
[Back]
Baylor
wins $1.3 million grant to study virus related to colon cancer-(Yahoo
News-19/04/2004)
The
National Institutes of Health recently awarded Baylor Research Institute
a $1.3 million grant to study a common virus suspected to play a role
in causing colon cancer. C. Richard "Rick" Boland, M.D., chief of gastroenterology
at Baylor University Medical Center at Dallas, will lead the research
effort. Colon cancer, one the most common cancers in America, affects
about 150,000 people yearly. Although lethal in late stages, with a cure
rate less than 10 percent for advanced metastatic cancer, 90 to 100 percent
of early stage colorectal cancers are curable.
In
the research study, Boland will examine the JC virus, a common virus carried
by approximately 80 percent of healthy people in their colons. People
who carry the virus, which is caught during childhood, show no obvious
ill effects. "Since most of us carry the virus, the virus itself is not
the culprit," Boland said. "It seems to exist in a latent state in most
people. But when the virus replicates, it can make mistakes or mutate.
We think it very likely causes a problem called chromosomal instability
and could be a trigger that starts the process that leads to colorectal
cancer." If the study experiments are successful in determining the role
of the JC virus, Dr. Boland plans to propose clinical trials that would
seek to develop an immunization strategy for colon cancer. These clinical
trials would be conducted in collaboration with Jacques Banchereau, director
of the Baylor Institute for Immunology Research in Dallas. "Ultimately,
we hope to develop a vaccine that might delay or prevent the emergence
of neoplastic lesions in the colon," Boland said. "Our success could have
significant implications for public health."
[Back]
'Key-Hole'
Surgery Appears Safe for Colorectal Cancer-(Reuters Health-09/04/2004)
Several
reports have shown that recovery after surgery is more rapid when patients
with colorectal cancer undergo a less-invasive laparoscopic, or "key-hole"
procedure, rather than conventional surgery. Now, new research indicates
that the laparoscopic approach does not adversely affect disease control
or jeopardize survival. There has been concern about the adequacy of surgery
with the laparoscopic approach after reports linked the procedure with
early recurrence at the site of incision. Until the long-term effects
were clear, it was recommended that laparoscopic surgery be limited to
the clinical trial setting.During
laparoscopic surgery for colorectal cancer, a tiny scope and instruments
are inserted through small incisions. A surgeon then draws the cancerous
tissue through a small incision, removes it, and then reconnects the colon.
In
a study reported in the medical journal The Lancet, Dr. Ka Lau Leung,
from the Chinese University of Hong Kong, and colleagues describe the
outcomes of 403 patients with colorectal cancer who were assigned to undergo
laparoscopic or conventional open surgery between 1993 and 2002. After
the procedures, the probability of survival after 5 years in the laparoscopic
group was 76.1-percent higher, but not significantly different from the
72.9-percent rate in the conventional group, the researchers note. The
probability of being disease-free after 5-years for the laparoscopic and
conventional groups were 75.3 and 78.3 percent, respectively.
Consistent
with previous reports, the laparoscopic surgery took longer to perform
than open surgery. The average operating time for laparoscopic surgery
was 189.9 minutes-about 45 minutes longer than the time needed for open
surgery. Postoperative recovery, as determined by factors such as time
to first bowel movement and hospital stay, was significantly accelerated
in the laparoscopic group. However, this benefit came at the expense of
a higher direct cost--$9297 per patient for laparoscopic procedure versus
$7148 per patient for open surgery. No differences were seen between the
groups in overall illness or operative mortality, the investigators point
out. Laparoscopic surgery did not worsen survival or disease control for
patients with colorectal cancer compared with open resection, and "its
benefits in reducing pain and allowing earlier postoperative recovery
were confirmed," the authors conclude.
[Back]
Currying
Favor-(Health Sciences Institute e-Alert-04/03/2004)
Last
week the FDA approved a new drug called Avastin; a breakthrough therapy
that fights cancer by impeding the blood supply that tumors need to survive.
Apparently this remarkable drug will help some patients add months or
even years to their lives. But Avastin may have some competition - not
market competition from another brand, but competition for effectiveness.
Because the most popular prescription drug on the market today (taken
by millions of people worldwide) actually stimulates the growth of new
blood vessels. Miracle drugs won't work many miracles if they simply undo
one another.
Cancer
cells thrive and multiply when they prompt the body to create new blood
vessels; a process called angiogenesis. When anti-angiogenesis therapy
was first conceived of more than 40 years ago it was dismissed as a farfetched
idea. Today it's considered the future of mainstream cancer therapy, and
as of last week Avastin is leading the vanguard of this new class of drugs.
The FDA approved Avastin specifically to treat cases of colorectal cancer
where the cancer has metastasized and spread to other areas of the body.
While additional trials are underway to determine Avastin's effectiveness
against other types of cancer, you can be certain that some oncologists
will want to prescribe Avastin for a variety of cancer types right away.
The question is: Will insurance companies cover off-label use of the drug?
That could be a sticking point, because a patient who takes Avastin for
a year can expect to pay more than $100 per day. Given that 150,000 new
cases of colorectal cancer are diagnosed each year in the U.S., it's no
wonder that analysts are predicting that Avastin's sales may approach
$2 billion a year for Genentech, Inc., the maker of the drug.
As with most drugs, Avastin use comes with a formidable list of possible
side effects, including high blood pressure, diarrhea, blood clots and
a lowered white blood cell count, which can increase the risk of infection.
Some patients have also reported internal bleeding and ruptures in the
colon. And Avastin has been shown to be effective only when used with
a program of traditional chemotherapy, which often subjects the body to
alarming stresses. Of course, for most cancer patients, the side effects
and the exorbitant cost of Avastin will be tolerable trade offs in exchange
for the promise of additional months or years of life. So it would be
a particular shame if they were taking another medication that actually
worked against their best efforts to survive. In the e-Alert "Missing
the Forest" (7/23/03), I told you about the concern that cholesterol-lowering
statin drugs may promote cancer. Few studies have been conducted in this
area, and so far the results are conflicting. One of the primary reasons
that further research needs to explore the statin/cancer question is this:
Statins have been shown to stimulate the growth of new blood vessels -
the very situation that Avastin is designed to reverse. It's impossible
to predict which drug would win out in such a confrontation. But with
the number of statin prescriptions estimated at well over 100 million
worldwide, you can be sure that there will be statin-users who will also
end up using Avastin.
Avastin
is not a preventive therapy, of course. But there is a natural botanical
that may provide protection against cancer in the same way that Avastin
fights cancer. In 2002 I received a newsletter from well-known cancer
researcher, Ralph W. Moss, Ph.D., in which he noted that in Sri Lanka
the cancer mortality rate per 100,000 is 26.1 for females and 29.3 for
males. The comparison of these numbers to America is unsettling: Cancer
mortality per 100,000 in the U.S. is 138.6 for women and an astounding
206.0 for men. He adds that this difference is probably not due to genetic
or hereditary factors, for two reasons: 1) the population of Sri Lanka
has a wide diversity of ethnic backgrounds, and 2) the cancer rates of
emigres from Sri Lanka to North America and Europe rise considerably within
just a generation or two. Researchers believe that one nutritional element
might be the key to the differences of these cancer statistics. In Sri
Lanka a typical diet includes large amounts of turmeric -a spice that
contains curcumin, used in curry powders. In his article, Dr. Moss lists
the following as the three important benefits of curcumin intake: * Rich
in antioxidants * A natural anti-inflammatory * Inhibits growth of new
blood vessels in tumors. It seems that the people of Sri Lanka may be
centuries ahead of the Western world in taking advantage of the cancer-fighting
benefits of an anti-angiogenesis agent.
[Back]
FDA
OKs First-Of-A-Kind Colon Cancer Drug-(ET-27/02/2004)
Genentech
Inc. began shipping its widely anticipated colon cancer-fighting drug
just hours after the government approved the novel biotechnology treatment.
Avastin is designed to choke the blood supply that feeds tumors and is
the first drug of its kind to be approved by the FDA. When used with chemotherapy,
has been found to extend the life of the sickest patients by an average
of about five months. Some 30 other experimental drugs based on similar
technology are in various states of human testing and large drug makers
such as Novartis, Bayer and Pfizer are in advanced development. Genentech
also said it's experimenting with Avastin in several other forms of cancer,
including kidney and lung.
The
idea is that tumors must form a network of blood vessels to survive -
and that shutting down that process, called angiogenesis, could fight
cancer in a manner completely differently than other treatments. That
theory was pioneered by Harvard University's Dr. Judah Folkman, who made
front-page news in 1998 with reports that his anti-angiogenesis drugs
had cured mice of cancer. But attempt after attempt to make such drugs
work in people failed. Genentech Inc. saw its stock plummet as recently
as 2002 when the drug failed to help breast cancer patients. But in May,
the South San Francisco-based company surprised Wall Street when it announced
that Avastin showed promise after doctors tried it in the sickest of colon
cancer patients. Analysts expect the drug, which will cost each patient
about $4,400 per month, to surpass $1 billion in sales in the next few
years.
In
a study of 800 people, half received intravenous Avastin in addition to
routine chemotherapy. Not only was tumor growth delayed in those getting
Avastin, but the Avastin patients lived about 20 months, five months longer
than those getting standard treatment. It was the first time in three
decades of research that an anti-angiogenesis drug was proven to help
people. Avastin occasionally causes some serious side effects, including
formation of holes in the colon that may require surgery to fix, impaired
wound healing and internal bleeding, the FDA said. More common side effects
are high blood pressure, fatigue, blood clots, diarrhea, appetite loss
and increased risk of infection because of decreased white blood cells.
[Back]
Hormone
Use May Cut Colon Cancer Risk in Women-(Reuters Health-03/03/2004)
Hormone
replacement therapy (HRT) with estrogen and progestin seems to reduce
the risk of colon cancer in women who are past menopause, new research
shows. However, the cancers that do occur seem to be more advanced than
those seen in non-HRT users. Most of the news regarding HRT in recent
years has been bad. Just this week, the National Institutes of Health
announced that the estrogen-only arm of the Women's Health Initiative
(WHI) trial was being stopped early after the therapy was tied to an increased
risk of stroke. This follows the termination of the estrogen/progestin
arm in 2002 due to an observed increase in breast cancer, thrombosis,
stroke, and heart disease events among HRT users. However, when the estrogen/progestin
arm was stopped, the WHI researchers did notice one potentially beneficial
effect for HRT-a decreased risk of colon cancer, according to a report
in The New England Journal of Medicine.
To
better understand the link between HRT use and colon cancer, Dr. Rowan
T. Chlebowski, from Harbor-UCLA Medical Center in Torrance, California,
and colleagues analyzed data from 16,608 women who participated in the
estrogen/progestin arm of WHI. Overall, HRT users were 44 percent less
likely to develop colon cancer than non-users, the researchers found.
"We were quite surprised to find that colon cancers in HRT users were
of higher stage than those seen in controls," Chlebowski told Reuters
Health. The cancers that occurred in HRT users usually affected more lymph
nodes and were more likely to have spread to other organs, the results
indicate.
"Our
findings are somewhat similar to what was seen (last year) in the trial
with Proscar (finasteride) and prostate cancer-overall risk is decreased
but severe disease is more likely," Chlebowski noted. "Interestingly,
among HRT users with colon cancer, those with antecedent vaginal bleeding
were the ones most likely to have advanced...disease," Chlebowski pointed
out. This bleeding may have slowed the clinical work-up so that the cancer
wasn't diagnosed until a more advanced state, he added. Despite all the
unfavorable reports, Chlebowski believes that HRT could still be a viable
therapy. "One strategy would be to see if the risks of HRT could be modulated
with other agents."
[Back]
More
Evidence Vegetarian Diet May Cut Cancer Risk- (Reuters Health-16/02/2004)
Eating
a meat-free, vegetarian diet may reduce the risk of colorectal cancer,
new research suggests. After following more than 10,000 people for 17
years, investigators found that vegetarians were 15 percent less likely
to develop colorectal cancer than meat-eaters. This study adds to the
"increasing scientific evidence" that a diet rich in fruit, vegetables
and fiber and low in meat-especially red and processed meat-can prevent
colorectal cancer, study author Dr. Miguel Sanjoaquin of the University
of Oxford, UK, told Reuters Health. However, Sanjoaquin cautioned that
only a small number of study participants -95--developed colorectal cancer,
making it impossible to determine if fewer vegetarians developed cancer
simply due to chance. Sanjoaquin noted that a previous study featuring
more cases of colorectal cancer confirmed these findings, and he added
that it makes sense that eating vegetarian could cut cancer risk.
The
fat in red meat increases the excretion of substances called bile acids,
he explained, which in turn produce other substances that encourage tumor
growth. Furthermore, meat contains natural compounds and substances formed
during processing and high-temperature cooking that can disrupt the normal
balance of cell growth in the colon, potentially triggering the cancer,
Sanjoaquin noted. Alternatively, substances in fruits and vegetables-staples
of the vegetarian diet-"may inhibit these adverse effects," he added.
During the current study, Sanjoaquin and his colleagues asked 10,998 adults
about their eating habits and other health parameters, then noted who
developed colorectal cancer. People were classified as non-vegetarians
if they ate meat or fish. Vegetarians included vegans, who avoid all dairy
and meat products.
Along
with a decreased risk of cancer from eating vegetarian, the investigators
found that frequent fruit eaters - consuming more than 5 servings of fruit
per week-were over 40 percent less likely to develop colorectal cancer.
Smoking, drinking alcohol and eating more than 15 slices of white bread
per week appeared to increase the risk of colorectal cancer, according
to the British Journal of Cancer report. Sanjoaquin said the fact that
white bread appeared to reduce cancer risk was "unexpected," and suggested
that people who ate large amounts of white bread might have simply had
a less healthy diet overall. Alternatively, he added researchers have
noted that eating large quantities of refined carbohydrates, such as those
found in white bread, may raise colorectal cancer risk, suggesting that
white bread itself may also play a role. "More research will be needed
to clarify this," Sanjoaquin said
[Back]
Erbitux
Lifts Hopes of Colon Cancer Patients-(Reuters-13/02/2004)
Advocacy
groups said patients with advanced colon cancer are hoping ImClone Systems
Inc's new drug, Erbitux, will improve their lives and help some survive
until more effective drugs come along. Patients typically live only 12
to 18 months after colon cancer has spread to other parts of their body.
Although Erbitux did not prolong the lives of such patients in clinical
trials, it did shrink tumors in 23 percent of those who had exhausted
other drug options. Erbitux, which was approved by U.S. regulators and
will be co-marketed by Bristol-Myers Squibb Co., works by blocking receptors
to a protein called epidermal growth factor that are found in large numbers
on the surface of many types of tumor cells. It is less toxic than many
older chemotherapy drugs, which tend to harm healthy tissues as they go
after cancer cells. "If you can shrink tumors and slow down their growth,
there's always a potential of extending a patient's life, and that's what
patients are hoping for," said Ernestine Hambrick, founder of Stop Colon/Rectal
Cancer Foundation.
Hambrick, a former colon cancer surgeon whose education and prevention
group is based in Chicago, said patients diagnosed with advanced colon
cancer for decades could only be helped by one drug, called 5-FU. But
survival times have doubled in the past decade with the addition of Pfizer
Inc's Camptosar and Sanofi-Synthelabo's Eloxatine. "Erbitux was tested
in the very sickest colon cancer patients, but now that it's approved,
many doctors will begin prescribing it for less-advanced patients in various
combinations with these other drugs," said Carolyn Aldige, president and
founder of the Cancer Research and Prevention Foundation.
Aldige, whose group is based in Alexandria, Virginia, said new combinations
using Erbitux might extend patient lives additional months, even though
no trials have yet demonstrated that. "It's not necessarily a breakthrough
drug, but by shrinking tumors, it can reduce pain, and that's a clear
potential benefit," Aldige said. Eribitux has also spurred some enthusiasm
in Canada, where it is awaiting approval. Barry Stein, president of the
Colorectal Cancer Association of Canada, has survived eight years after
being diagnosed with advanced colon cancer. "I'm not supposed to be here,
but I am thanks to numerous surgeries to remove tumors" and treatments
approved in recent years, Stein said. He said each new approved drug has
the potential to extend life a bit longer. "And the longer you live with
the disease, the greater chance you'll be around until better drugs are
found." "Every new advance lifts your spirits and gives you the encouragement
to keep on fighting, which influences your quality of life," Stein said.
[Back]
Colorectal
Cancer: A Family Matter-(ET-10/02/2004)
It's
a medical detective story that starts with the emigration of a married
couple from Germany to Pennsylvania in the early 1700s and ends with implications
for today's programs to screen for the risk of colorectal cancer. The
couple had 11 children, a typically large family for that era. Those children
married and had families of their own, until their descendants numbered
in the thousands, a new study reports. And over the decades and centuries,
an unexpectedly large number of those descendants were diagnosed with
cancer. Most were cancers of the colon and rectum, but there also were
other tumors such as endometrial cancer and ovarian cancer among the women.
It wasn't until recently that researchers, armed with the tools of modern
genetics, were able to establish the link.
The
original German immigrants brought with them a mutation of a gene designated
MSH2, a mutation that predisposes people to develop some cancers, particularly
colorectal cancer. The mutation appears to have originated with one of
the married pair. Each of their children had a 50-50 chance of inheriting
what is called the "founder mutation," and each person with that mutation
had a 50 percent chance of passing it on to a child. The existence of
the mutation was first noticed in 1997 by Riccardo Frodde, a geneticist
then at Leiden University in the Netherlands, who found evidence of it
in more than 50 families there. The story then moved to the United States,
where a group of researchers headed by Dr. Henry T. Lynch, a professor
of preventive medicine at the Creighton University School of Medicine
in Nebraska, found the same mutation in members of seven apparently unrelated
families with a history of colorectal cancer. That discovery indicated
the families might, in fact, be related, says Stephanie M. Coronel, a
genetic research assistant in Lynch's laboratory. "That is how we started
doing genealogical work, looking at different sites on the Web," Coronel
says.
Those
studies pointed toward a common origin of the mutation, and they drew
in another researcher, Dr. Albert de la Chapelle, a professor of cancer
genetics at Ohio State University. He had found the same mutation in two
other families. "It was pure coincidence that Dr. Lynch and I, who knew
each other, identified the same mutation in some of his patients and some
of my patients," de la Chapelle says. "It was not very difficult to start
putting two and two together." The result, reported in the Journal of
the American Medical Association, was detection of the founder mutation
in 61 members of the nine families in admittedly partial testing; only
137 of 566 members of the families have been tested. "We have shown by
now that four of the nine families descended from the founder couple,
and we are almost 100 percent certain that all do," de la Chapelle says.
This is a big surprise, he says, because founder mutations traditionally
have been seen only in relatively small, isolated populations, such as
Icelanders and Ashkenazi Jews. "You do not expect to see it in a mixed
population, such as we have in the United States," de la Chapelle says.
The
implications of the discovery may extend to many Americans outside the
tested families, Coronel says, since it is estimated that 10 percent of
all colorectal cancers are hereditary. The presence of colorectal cancer
in a family can indicate a need for genetic testing, she says. "If you
have a family history of colorectal cancer, or a parent or sibling diagnosed
at an early age, you can call your local genetic counselor," Coronel says.
"If a mutation is found, it can be referred to us." The fact that the
mutation appears to be widespread could help make genetic screening more
efficient, de la Chapelle says. Researchers could start by running a test
for the suspect gene, skipping more costly testing for a variety of genes.
Testing for all cancer-causing mutations costs about $2,500, he says,
so it would be less expensive to start by looking for just one mutation.
"If this is as common as we think, all testing should look at this first,"
de la Chapelle says
[Back]
Catching
the Culprit in Colon Cancer-(HealthDayNews-03/02/2004)
The activation of a particular cellular receptor greatly increases the
development of precancerous polyps in the intestine, says a Vanderbilt-Ingram
Cancer Center study in online edition of Nature.This is the first time
that scientists have found evidence of this activation process. The findings
may suggest a new strategy for preventing colorectal cancer by preventing
activation of this cellular receptor.The results also raise caution about
a possible increased risk of colorectal cancer among people who take drugs
that activate this receptor. Such drugs are currently in clinical development
to treat obesity and atherosclerosis.In this study, researchers found
that mice with a specific genetic mutation - one that's found in 80 percent
of people with colorectal cancer - had a fivefold increase in the number
of larger colon polyps when they were given a compound that binds to the
peroxisome proliferator-activated receptor delta (PPAR-delta)."This is
extremely significant because it is these larger polyps that are most
likely to develop into intestinal cancer," Dr. Raymond N. DuBois, associate
director of cancer prevention, control and population-based research at
Vanderbilt-Ingram, says in a prepared statemnent
[Back]
High-carb
diets may increase cancer risk-(USA TODAY-04/02/2004)
Diets
filled with certain high-carbohydrate foods may increase the risk of colorectal
cancer in women, according to a study published today in the Journal of
the National Cancer Institute. Cakes, cookies and other quickly digested
foods score high on the "glycemic index," a measure of the rate at which
carbohydrates are processed into sugar. A sudden surge in blood sugar
prompts the body to produce a matching rush of insulin, which helps convert
the sugar, or glucose, into energy. Insulin stimulates cells to divide
and keeps them alive longer than normal. That could encourage the growth
of tumors, the study says.Brown rice and wheat breads, in contrast, contain
carbs that are absorbed more slowly by the body.
Researchers
at Harvard Medical School and Brigham and Women's Hospital in Boston followed
more than 38,000 women for an average of nearly eight years and identified
174 with colorectal cancer, according to the article. Women in the study
with high dietary glycemic loads were more than twice as likely to develop
colorectal cancer.Some health experts say the study, although preliminary,
is intriguing."You may pay for that sugar high in more ways than you realize,"
said Michael Thun, head of epidemiologic research for the American Cancer
Society. He noted that results of similar studies have been mixed, however,
and that more research is needed. Others note that measuring glycemic
loads is complicated. "It's difficult for the average person to make sense
of this," said dietitian Melanie Polk, director of nutritional education
for the American Institute for Cancer Research. "An easier guide is to
base your diet on fruits, vegetables, beans and whole grains.
[Back]
Heart
Disease Marker Now Tied to Colon Cancer-(HealthDayNews-03/02/2004)
A
blood chemical that predicts heart attacks and strokes also seems to foretell
who is likely to develop colon cancer, new research shows. Irritation
in the intestines, such as that associated with inflammatory bowel disease
(IBD), has long been known to increase a person's risk of colon and rectal
cancer. The new study "puts forward the idea that low-grade inflammation
could be a risk factor for colon cancer" in people without severely aggravated
intestines, says study leader Dr. Thomas Erlinger, an internist and epidemiologist
at Johns Hopkins Medical Institutions.
The
substance, C-reactive protein (CRP), is a marker of general inflammation
throughout the body. People who developed colon cancer during the study
had a higher CRP count at the start than those who were free of the disease.
The study didn't find a direct connection between CRP and rectal tumors,
though the number of rectal cancer cases was small. A report on the findings
appears in the Feb 4 issue of the Journal of the American Medical Association.
CRP was discovered in 1930 in the blood of patients with serious pneumonia.
More recently, scientists have learned that people with more of the protein
in their blood are at greater risk of heart attacks, strokes and several
other major illnesses.
In
the latest work, Erlinger and his colleagues compared CRP levels and colorectal
cancer risk in nearly 23,000 residents of Washington County, Md., participating
in a long-term study of heart disease and cancer. A blood test for the
protein was included in a battery of exams at the start of the project,
which ran between 1989 and 2000. By the end of the study, 131 men and
women were diagnosed with colon cancer, and 41 got rectal cancer. The
risk of colon cancer for people in the top quarter of initial CRP levels
was about 2.5 times higher than for those in the bottom quartile. Smokers
and people with bowel diseases such as Crohn's and colitis are known to
have increased odds of developing colon cancer. But even after accounting
for these risk factors, the link between elevated CRP and colon tumors
persisted, Erlinger says. If colon cancer is related to inflammation,
aspirin and other anti-inflammatory drugs could in theory prevent the
disease. And indeed, the researchers did see some hints that people who
took these medications were less likely to develop colon tumors. "They
did have a lower risk but we really didn't have good data there," Erlinger
says.
More
studies are need to address the question, he adds. Dr. Boris Pasche, director
of the cancer genetics program at Northwestern University, calls the results
"an interesting first study" that should encourage further research into
the health effects of simmering inflammation. "Maybe the same people with
a higher risk of cardiovascular disease also have a higher risk of colorectal
cancer," says Pasche, co-author of an editorial accompanying the journal
article. But it's not yet clear that elevated CRP predicts colon cancer
or simply reflects tumors that are already present but too small to generate
symptoms. Erlinger's group tried to account for this possibility, but
since they had only one reading of the protein they weren't able to fully
exclude it in their analysis. "If you argue that there is a relationship
[between CRP and cancer] you would expect that the CRP value may increase
over time prior to the diagnosis of colon cancer," Pasche says.
[Back]
New
Treatments Improve Outlook for Colorectal Cancer-(ET-12/01/2004)
A
new study published in the Journal of Clinical Oncology (Vol. 22, No.
1: 23-30) suggests the recently approved drug oxaliplatin can improve
survival and should become standard first-line treatment for patients
with advanced colorectal cancer. Experts say the research illustrates
just how quickly new drugs - and new ways of administering older drugs
- are revolutionizing the treatment of this deadly disease. "Today, fewer
stage III colorectal cancer patients relapse and more and more stage IV
patients are alive at 2 or 3 years, likely as a result of using these
new regimens," said Alberto Sobrero, of the Osepedale San Martino in Genoa,
Italy, who wrote an editorial accompanying the study.
Colorectal
cancer is the second leading cause of cancer related deaths in the United
States. The American Cancer Society estimates that 147,000 Americans will
be diagnosed with colorectal cancer in 2004, and 56,730 people will die
from it. Early detection of this disease can prevent many of these deaths,
but screening rates are low and many people aren't diagnosed until the
cancer is advanced and liable to spread throughout the body. People with
advanced disease are less likely to survive than people whose colon cancer
is found at an early stage.
For
years the standard treatment to try to prevent this spread, and also to
treat the cancer if it had already spread, was chemotherapy with 2 drugs,
5-Fluorouracil (5-FU) and leucovorin. Usually the drugs were given together
as an intravenous injection over a few minutes. Although this regimen
helped some patients, many did not benefit. Things began to change in
the late 1990s when French doctors led by Aimery de Gramont, MD, devised
a more effective and less toxic way of giving these drugs. Instead of
giving the drugs all at once, they gave the 5-FU by continuous intravenous
infusion over 2 days every 2 weeks along with injections of the leucovorin.
More than twice as many patients on that regimen experienced major tumor
shrinkage with fewer side effects (Journal of Clinical Oncology Vol. 15,
No. 2: 808-817). This treatment regimen is now commonly called the de
Gramont regimen.
At
the same time, a new drug called irinotecan, given alone, was helping
patients with widespread colorectal cancer who were no longer responding
to 5-FU and leucovorin. The drug was even more effective when given along
with 5-FU and leucovorin. Researchers led by Leonard Saltz, MD, found
that patients given all 3 drugs were more likely to have tumor shrinkage
and live more than 2 months longer than patients who only received 5FU
and leucovorin (New England Journal of Medicine Vol. 343, No. 13: 905-914).
This treatment is now known as the Saltz regimen.
Oxaliplatin,
which was approved by the US Food and Drug Administration in August, 2002,
has shown even more promise when given along with 5-FU and leucovorin.
Results presented at an oncology meeting last year suggested that this
drug combination could better prevent cancer recurrence in people with
large tumors or tumors that had spread to the lymph nodes. In the new
study, doctors at the University of North Carolina, Chapel Hill, and other
institutions, found that patients who received this drug combination lived
longer than patients receiving 5-FU/leucovorin combinations containing
irinotecan.
The
study enrolled 795 patients who had widespread colorectal cancer. They
were divided into 3 groups. One group received oxaliplatin and 5-FU and
leucovorin, with the 5-FU given by infusion over 2 days. A second group
received irinotecan and 5-FU and leucovorin. This time, the 5-FU and leucovorin
were given by injection over a few minutes. The third group was given
irinotecan and oxaliplatin together, with no 5-FU or leucovorin. The oxaliplatin,
5-FU/leucovorin combination held the tumor in check the longest and appeared
to help patients live longer. It also caused the fewest side effects.
The only major problem for patients on this treatment was numbness and
tingling that eventually went away in most cases. The other regimens were
far more toxic, causing more nausea and vomiting and also severe diarrhea.
Because
the oxaliplatin treatment is more effective and less toxic, the study
authors conclude that it should become standard therapy. Editorialist
Sobrero agreed, but noted that because there has been such a substantial
improvement in treating colorectal cancer recently, other drug combinations
now being tested may prove just as useful. The drug bevacizumab (Avastin),
for instance, appears to help patients with advanced colorectal cancer
respond better to treatment and live longer, when it is given in combination
with 5-FU and leucovorin. Avastin is an anti-angiogenesis drug. It prevents
blood vessel growth and is thought to kill tumors by preventing them from
being nourished. Avastin is on a fast track at the FDA and may receive
approval this year. Another new therapy now in trials is capecitabine,
a form of 5-FU administered as a pill. Replacing the cumbersome 5-FU infusion
with a pill would be a great benefit to patients if it also proved to
be effective.
[Back]
Vitamin
D Has Role in Colon Cancer Prevention-(ET-15/12/2003)
Vitamin D may be more important to colon cancer prevention than previously
believed, according to a study published in the Journal of the American
Medical Association (Vol. 290, No. 22: 2959-2967). The study examined
people with no symptoms of colon cancer to determine what role diet, exercise,
smoking, and other behaviors played in the development or not of colon
polyps, small growths in the colon that can turn into cancer if they aren't
removed. "Higher levels of vitamin D were associated with a lower risk
of serious colon polyps," said lead study researcher David Lieberman,
MD, chief of gastroenterology at the Portland Veterans Affairs (VA) Medical
Center and Oregon Health Sciences University. "There have been some studies
suggesting this, but our data are compelling."
The
role of vitamin D in colon cancer prevention is still a topic of debate,
said Durado Brooks, MD, director of prostate and colorectal cancer for
the American Cancer Society. Previous research has not been able to determine
conclusively whether vitamin D alone is helpful, whether it must be consumed
with calcium to have a protective effect, or whether calcium alone is
really the important nutrient. "Past studies have given more credence
to calcium, and this suggests we need to look at vitamin D as potentially
as important as calcium," Brooks said.
The
new study, conducted at 13 VA medical centers, followed more than 3,000
people for 3 years. All the participants were between the ages of 50 and
75, and almost all of them (97%) were men. Everyone in the study had a
colonoscopy to look for colon polyps, and the researchers compared people
who had advanced (large) polyps with those who didn't. The researchers
asked the participants about many factors that could influence whether
they developed colon polyps: smoking history, alcohol use, physical activity,
family history of colon cancer, use of aspirin or other non-steroidal
anti-inflammatory drugs (NSAIDs), diet, and weight. Men who consumed more
vitamin D in their diet each day were less likely to develop colon polyps,
and men who consumed the most of the vitamin (more than 645 IUs, or international
units) daily reduced their risk the most.
Vitamin
D is found in fortified milk, salmon, cod liver oil, sardines, and mackerel.
Spending time in the sun also helps the body produce vitamin D. However,
too much vitamin D can cause nausea, constipation, weakness, and other
problems, so Lieberman cautioned against overdoing it. According to the
National Institutes of Health, people aged 19-50 need 200 IUs daily (in
either their diet or in supplements) for adequate nutrition, while people
between 51 and 69 should get 400 IUs each day. People 70 and older need
600 IUs of vitamin D each day. The Institute of Medicine's Food and Nutrition
Board recommends an upper limit of 2,000 IUs of vitamin D for most children
and adults, and no more than 1,000 IUs for babies under 12 months.
Cereal
fiber was another important dietary factor for colon cancer prevention.
People who ate more than 4 grams per day had a significantly lower risk
of colon polyps. Exercise, calcium, and multivitamins also had a small
benefit. Taking NSAIDs had a significant protective effect. Men who took
NSAIDs daily were only two-thirds as likely to get colon polyps as men
who did not take the drugs. Other studies have also suggested these drugs
can help prevent colon cancer, but because they can cause side effects
including ulcers and stomach bleeding, experts say it's too soon to recommend
them as a routine method of prevention. "People need to talk to their
doctor about whether [NSAIDS] would be helpful for them," said Brooks.
The
study also identified some lifestyle and medical factors that raised a
person's risk of getting colon polyps - and thus, colon cancer. Of these,
smoking was the most serious. Smoking nearly doubled the risk of having
polyps. Eating a lot of red meat and having more than one alcoholic drink
every day also raised risk. "These data support relatively simple and
safe recommendations that may reduce the risk of colon cancer," said Lieberman.
"Stop smoking, reduce alcohol and red meat consumption, take a multivitamin,
exercise regularly, and consume vitamin D, calcium, and cereal fiber in
your diet."
Regular
screening for colon cancer is also important, he noted, especially for
people who have a relative who had the disease. In this study, people
with a family history of colon cancer had a 66% greater risk of developing
colon polyps. Other studies have also found that family history increases
the risk of developing colon cancer. For this reason, the American Cancer
Society recommends people with a family history begin screening at younger
ages (before age 50) and/or get more frequent screenings. Colon cancer
is the fourth most common cancer in the United States, but the second
deadliest. ACS estimates that more than 57,000 Americans die from this
disease each year; only lung cancer kills more people. Screening can catch
changes in the colon before they become cancerous, or find cancer in its
early stages, when chances of a cure are better.
[Back]
'Virtual'
Colonoscopy Effective at Finding Polyps-(Reuters-02/12/2003)
The
latest CT-scan technique that yields three-dimensional images of the bowel
is faster, simpler and safer than the standard colon exam for preventing
colon cancer, researchers say. If the finding is confirmed and some lingering
questions about the technique are answered, such "virtual" colonoscopies
could become commonplace, said Martina Morrin and Thomas LaMont in an
editorial in the New England Journal of Medicine, where the study will
be published. The study was presented at the annual meeting of the Radiological
Society of North America in Chicago. Using a scan avoids having to sedate
a patient and doctors do not have to put a probe up the length of the
colon, both of which can cause problems. However, people being screened
using either method will still have to follow an often distasteful regimen
for cleaning the bowel. And if something suspicious is found using the
CT scan technique, patients will still need a conventional colonoscopy
to have suspicious polyps removed.
Colon
cancer kills 60,000 people in the United States each year, making it the
second leading cause of cancer deaths. Having a colonoscopy every three
to five years after age 50 virtually eliminates that risk. Only a third
to half of the population is screened for colon cancer, and a safer, simpler
technique might get more people into screening programs. Morrin and LaMont
said it was unclear whether virtual colonoscopies would save money or
whether health insurance companies would pay for the procedure. Also unclear
was whether doctors should remove small polyps found by the CT scan right
away.
The
research team, led by Perry Pickhardt of the University of Wisconsin Medical
School, used CT scanners with multiple detectors that picked up fine details
more quickly than conventional scanners. They also had special software
that permitted doctors to view the colon in three dimensions and ignore
any material lingering in the bowel. Previous attempts to look for colon
cancer with CT scanners have used less sophisticated techniques that produced
two-dimensional images. Most hospitals lack the equipment and software
to do such screening scans. With a conventional colonoscopy, doctors use
drugs to make patients groggy and unable to remember the experience. Too
much sedation can be dangerous, especially if the tube used to search
for polyps punctures the colon and the patient is not conscious enough
to complain of the pain. In such cases, the outcome can be deadly.
People
undergoing a virtual colonoscopy are fully awake but not always comfortable
because air or carbon dioxide is pumped into the colon to expand it and
make it easier for the CT scanner to view. In the Pickhardt study, the
scanning took half the time of a standard colon exam. Although 54 percent
said a virtual colonoscopy was more uncomfortable than a regular one --
probably because there were no drugs to make them sleepy -- 68 percent
said the procedure was more acceptable. The Pickhardt team said doctors
and hospitals that do virtual colonoscopies should be prepared to immediately
perform a conventional colonoscopy to remove suspicious polyps, if only
because the patient's colon is already cleaned out.
[Back]
Catching
Colorectal Cancer in its Tracks-(HealthDayNews-02/12/2003)
Colorectal
cancer patients whose disease is detected by routine screening have an
earlier stage of cancer and lower health-care costs than patients diagnosed
with colorectal cancer because of symptoms, says a study in the December
issue of Gastroenterology. Researchers from the Fred Hutchinson Cancer
Research Center and the Washington state HMO Group Health Cooperative
found health-care costs for patients with colorectal cancer detected by
screening was $24,636 for the three months before diagnosis to 12 months
after diagnosis. That amount was $31,128 for patients whose colorectal
cancer was detected because of symptoms. "By shifting diagnosis to earlier,
asymptomatic stages, screening programs catch cancer at an earlier, more
curable stage and significantly reduce the costs of both diagnosis and
treatment among people with cancer," study author Dr. Scott D. Ramsey,
of the Fred Hutchinson Cancer Research Center, says in a prepared statement.
More
than 90 percent of people diagnosed with early-stage colorectal cancer
survive more than five years after diagnosis, compared with 8 percent
of people diagnosed with late-stage colorectal cancer.
[Back]
Treatment
Before Surgery Best for Rectal Cancer-(Reuters Health-21/10/2003)
Chemotherapy
plus radiation before surgery improves the control of rectal cancers,
new research shows. Moreover, such treatment is less toxic than when it
is given after surgery. For rectal cancers that haven't spread to other
sites, surgery is the standard initial treatment, followed by chemotherapy
plus radiation (CRT). Recent studies, however, suggest that pre-operative
CRT may be advantageous. "Theoretically there are...advantages for (pre-operative)
treatment over post-operative treatment," Dr. Rolf Saur, from Strahlenklinik
in Erlangen, Germany, told Reuters Health. "Therefore we started this
protocol comparing both modalities in the mid 1990s and closed it last
year."
In
the trial, 823 patients with rectal cancer were treated with CRT either
before or after having the cancer removed. After treatment, the patients
were followed for around 43 months. The results were presented this week
in Salt Lake City at the annual meeting of the American Society for Therapeutic
Radiology and Oncology. Pre-operative CRT was better at controlling the
cancer than post-operative CRT, the authors reported. Survival, however,
was similar with either approach. Still, fewer side effects were noted
when CRT was given before rather than after surgery. "We saw a significant
decrease in acute toxicity, especially in diarrhea, as well as in late
toxicity," Saur said. Moreover, pre-operative CRT was better than post-operative
CRT at helping patients with low-lying tumors avoid the need for a colostomy.
[Back]
Ginger
Snaps Colon Cancer Growth in Mice-(HealthDayNews-28/10/2003)
Ginger
prevents the growth of human colorectal cancer cells in mice, new research
has found. But don't count on your spice rack to prevent cancer just yet
because an American Cancer Society spokesman cautions that the research
is very preliminary. "Ginger has been used since antiquity for home remedies,"
says the lead researcher, Ann Bode, assistant director of the University
of Minnesota's Hormel Institute. It has been used as a digestive aid and
for seasickness and motion sickness, she adds, "but it's never really
been tested for its effect on colon cancer."
Bode
and her colleagues fed 20 mice a half milligram of [6]-gingerol, the main
component in ginger, three times a week, then injected human colorectal
tumor cells into the mice. Control mice were treated the same but their
food had no gingerol. Fifteen days after the cells were injected, the
first tumors showed up. Thirteen tumors of a size that could be measured
were found in the control mice, but only four were found in the gingerol-treated
mice. Those who ate the gingerol feed had fewer measurable tumors and
smaller tumors. By the 28th day after injection, all mice in the control
group had tumors of measurable size, but it took the gingerol-treated
group until the 38th day to have tumors of measurable size, and even then
one mouse had no measurable tumors.
Bode
discussed her findings at a teleconference from the American Association
for Cancer Research's annual conference in Phoenix. "The ginger component
we used is a principal component of ginger root," Bode says. Depending
on how the spice is processed, the amount of gingerol in ginger root varies,
she adds, noting, "We really don't know how much ginger root you would
have to eat to get the same effect." Among people who eat a lot of ginger,
she says, she has heard of no reported toxicity. About 147,000 new cases
of colon or rectal cancer are expected to be diagnosed this year, according
to the American Cancer Society, with more than 57,000 deaths. Exactly
how the ginger might slow tumor growth isn't known, Bode says. "It may
directly act on the cancer cells by inducing cell death," she says.
But
Dr. Herman Kattlove, a spokesman for the American Cancer Society, doesn't
think much should be made of the finding just yet. "Compounds are discovered
almost daily that will do this [in the lab]," he says. "Very few make
it past that point." So it appears to be too soon to up your intake of
such ginger-containing foods as ginger ale, ginger between sushi servings,
or ginger snaps and expect colorectal cancer protection. "We probably
already have 20 or 30 drugs that will work better than this," says Kattlove,
adding, "Mice are very easy to treat." Still, he says, "it's nice to see
people are looking for new [cancer-fighting compounds.] It may turn out
to be useful." Even if it does, however, Kattlove says human applications
are probably at least a decade away. On its Web site, the American Cancer
Society urges people with cancer to consult their physician before taking
ginger (sometimes recommended to reduce the nausea that can accompany
chemotherapy drugs) because it has the potential to interfere with blood
clotting and prolong bleeding time.
[Back]
Aspirin
Suppresses Cells That Lead to Colon Cancer-(Reuters Health-10/11/2003)
Regular
use of aspirin seems to suppress abnormal cells that can lead to colon
cancer, new research suggests. Known as aberrant crypt foci (ACF), these
abnormal cell clusters are thought to develop into colon cancer. Findings
from animal studies have suggested that aspirin suppresses ACF, but no
study has ever looked at aspirin's effect on ACF in humans. To investigate,
Dr. B. Shpitz, from the Meir General Hospital in Kfar Sava, Israel, and
colleagues tested for ACF in samples obtained from 194 colon cancer patients
during colon removal. Fifty-nine of the subjects reported regular use
of low-dose aspirin for at least 1 year before surgery. As the researchers
report in the medical journal Gut, nearly 76 percent of the samples from
non-aspirin users contained ACF, compared with only 36 percent of the
samples from aspirin users.
When
the analysis was limited to samples from the last portion of colon --
a common site for cancer -- aspirin use was tied to a 53 percent drop
in the rate of ACF. Moreover, the investigators found that aspirin use
seemed to reduce ACF density, especially in the last portion of colon.
Also, such therapy was linked to a reduction in dysplastic ACF--the type
most strongly linked to cancer. "This study has provided the first evidence
of (a preventive) effect of low-dose aspirin on ACF in humans," the authors
note. Further studies are needed to determine how aspirin achieves this
effect, they add.
[Back]
Hard
Alcohol Ups Risk of Colon Cancer-(HealthDayNews-13/10/2003)
If
you've given up wine in favor of martinis, you might want to give wine
another chance. That's because new research found people who consumed
more than nine drinks a week that contained distilled spirits, such as
vodka and whiskey, were three times more likely to have common types of
colorectal cancer. Wine, on the other hand, appeared to cut that risk.
The study is being presented Oct. 13 at the American College of Gastroenterology
annual meeting in Baltimore. "We found a strong association between spirits
and the presence of left-sided neoplasia [a lesion on the colon that may
be cancerous]," says one of the study's authors, Dr. Gurvinder Sethi,
an assistant instructor in medicine at Stony Brook University in Stony
Brook, N.Y. "The risk was 3.3 times higher than for people who didn't
drink at all."
Colorectal
cancer is one of the most common cancers, taking more than 57,000 lives
annually, according to the American Cancer Society. This year, the cancer
society estimates, more than 145,000 people will be diagnosed with colorectal
cancer. Dr. Joseph Anderson, an assistant professor of medicine at Stony
Brook University who was also involved in the research, says the study
was designed to see whether colorectal cancer screening recommendations
needed to be changed for people who drank alcohol. For the research, almost
2,000 volunteers were recruited to have screening colonoscopies. A colonoscopy
is a test designed to look for colon cancer. Using a thin, flexible tube
equipped with a light and a camera, doctors can examine the length of
the colon. The average age of the study participants was 57 and they were
equally male and female, Anderson says. About 90 percent were white and
all were from the Stony Brook area, which Anderson describes as affluent.
Along
with a colonoscopy, information was gathered from each volunteer on drinking
history, weight, family medical history, diet, smoking history, education
and exercise. The researchers found those who drank more than nine beverages
containing spirits a week had three times the risk of having cancer or
a suspicious lesion found during their colonoscopies compared to people
who didn't drink at all. Heavy beer drinkers appeared to face about double
the risk, but Anderson says the difference wasn't statistically significant.
Drinking wine appeared to have a protective effect, and reduced the risk
of having cancer or a suspicious lesion, Anderson says. Anderson says
he's not sure why spirits would be associated with more suspicious lesions.
Dr.
Ann Silverman, a gastroenterologist at William Beaumont Hospital in Royal
Oak, Mich., says it's possible there may be chemicals involved in the
processing of these products, or it could be another factor altogether,
such as a history of aspirin use, that the volunteers had in common. Because
the group of people drinking more than nine glasses of spirits a week
only comprised 66 people, Silverman says, the sample is too small to really
draw any conclusions. "I think the results are interesting, but it's too
preliminary to make any recommendations or suggest screening changes,"
she adds. Anderson says the most important thing people need to remember
is that "lifestyle, including alcohol consumption, has an impact on your
risk of getting colorectal [cancer]."
[Back]
Over
Time, Vitamins May Lower Colon Cancer Risk-(Reuters Health-07/10/2003)
Taking
multivitamins may modestly reduce a person's chances of getting colorectal
cancer, but not right away. There is a long interval between the start
of taking multivitamins and when the apparent protective effect kicks
in. These new findings come from the Cancer Prevention Study II Nutrition
Cohort, in which researchers examined the relationship between current
and past use of multivitamins and the occurrence of colorectal cancer
among more than 145,000 predominantly white, middle-aged or elderly adults.
"This study was conducted to follow-up on a report from the Harvard Nurse's
Health Study, indicating that prolonged multivitamin use might substantially
reduce risk of colon cancer," Dr. Eric J. Jacobs from the American Cancer
Society in Atlanta, Georgia, told Reuters Health.
At
enrollment in 1992-1993, participants provided information on current
use of multivitamins. All of the subjects had also provided information
on multivitamin use some 10 years earlier in 1982, as part of another
study. This allowed the investigators to examine the potential effects
of past use of vitamins, without relying on what people recalled. Roughly
half of the group reported no multivitamin use, 8 percent said they took
a multivitamin regularly (four or more times per week) only in the past,
and 19 percent said they regularly took a multivitamin only recently.
During follow-up from 1992 to 1997, 797 cases of colorectal cancer were
detected, the research team reports in the American Journal of Epidemiology.
After adjusting for "health conscious" behaviors, participants who were
regular multivitamin users 10 years before the start of the study had
an approximately 30 percent less risk of developing colorectal cancer.
Those who had only recently begun to use multivitamins "were not at reduced
risk," Jacobs said. "Our study, together with results from previous studies,
provides limited evidence that some component in multivitamins may modestly
reduce risk of developing colorectal cancer," Jacobs told Reuters Health.
The
exact component or components of multivitamins that may be protective
remain unclear. The researcher emphasized, however, that the American
Cancer Society does not currently recommend using multivitamins for cancer
prevention, as the evidence is "insufficient." "In contrast, the ACS strongly
recommends that all Americans 50 and over get a screening test for colorectal
cancer," Jacobs said. "Colorectal cancer screening has been proven to
substantially reduce the risk of dying from colorectal cancer."
[Back]
Drinking
doubles risk of colon cancer among men: report-(AFP-13/09/2003)
Men
who drink alcohol on a regular basis are twice more likely to develop
colon cancer than those who do not, a report said, citing a study by a
Japanese cancer center. The research team, led by Kenji Wakai, a senior
researcher of the Aichi Cancer Center, reached the conclusion after studying
the lifestyle of about 58,000 men and women, Kyodo news agency said. Wakai
and his fellow researchers studied the lifestyle of the sample people,
who were aged between 40 and 79, over a three-year period to 1990 and
conducted follow-ups that lasted seven-and-a-half years on average. The
team found that about 420 of the 58,000 people developed colon cancer
during the follow-up period, and calculated the case rate of colon cancer
among drinkers, non-drinkers and those who were abstaining from drinking.
The
team found that the rate of developing colon cancer was nearly twice as
high among drinking males than non-drinkers. Kyodo also quoted Wakai as
saying giving up alcohol would not reduce the risk immediately as those
who abstained from alcohol during the follow-up period had more or less
the same propensity of developing colon cancer as those who were drinking.
For women, the study found that only those who were abstaining from alcohol
had higher risks but the team has yet to find the explanation, the report
said.
[Back]
Chemotherapy
Plus Radiation Best for Rectal Cancer-(Reuters Health-17/09/2003)
New
research suggests that patients with large rectal cancers may do better
if chemotherapy is added to radiation before the tumor is removed surgically.
Surgery is a useful treatment for rectal cancer that hasn't spread or
metastasized. Sometimes, when these tumors are large, radiation is given
first in an attempt to "shrink" the cancer. However, it was unclear if
also giving chemotherapy before surgery was any better than just giving
radiation. The new findings are based on a study of 403 rectal cancer
patients who were treated with radiation before surgery. Of these subjects,
215 also received chemotherapy with a drug called 5-fluorouracil.The
patients were followed for around five years.
Compared
with radiation alone, the combination treatment resulted in a greater
percentage of patients showing tumor shrinkage, lead author Dr. Christopher
H. Crane, from M. D. Anderson Cancer Center in Houston, and colleagues
report. The combination therapy, however, did not improve patient survival,
the authors note in the International Journal of Radiation Oncology, Biology,
Physics. For patients with tumors near the anus, combination therapy was
better than radiation alone at preventing the need for a colostomy and
allowing normal bowel function. The results of the current study suggest
that adding chemotherapy to radiation may improve certain rectal cancer
outcomes, the authors note. It's hoped that an ongoing European study,
currently under way, will define the role of chemotherapy, they add.
[Back]
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