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The following are extracts of recent cancer-related news items from local daily newspapers.
Do you see something you want to know more about? Would you like to be sent the whole article? Please contact us.

 

Colon Cancer

Drug combination reduces colon cancer risk: study (Reuters - 14/04/2008)
Bowel cancer screening halves emergency admissions, cuts deaths- (ANI- 2/12/2007)
Genes May Explain Role of Race in Colon Cancer Risk- (HealthDay- 28/11/2007)                                                                                            Transition from polyp to cancer age-dependent-(Reuters- 22/11/2007)          Drug Helps Fight Late-Stage Colon Cancer in Some Patients- (HealthDay- 14/11/2007)
Study Challenges Colon Cancer Surgery Follow-Up (HealthDay- 13/11/2007)  New versions of curry ingredient to fight cancer (Reuters- 6/11/2007)           More power to turmeric in its fight against cancer (IANS- 5/11/2007)           
New test for inherited bowel cancer-(Yahoo News- 17/10/2007)                  
Long-Term Aspirin Use Cuts Colorectal Cancer Risk, But ... (HealthDay News-23/08/2005)                                                                                 
Poor less likely to be screened for colon cancer (Reuters Health-25/07/2005)  
No Evidence Calcium Fights Colon Cancer (HealthDayNews-20/07/2005)  
Chinese most prone to colorectal cancer in Asia (Reuters18/07/2005) 
Sigmoidoscopy Helps Catch Colon Cancer-(HealthDay News-05/07/2005)  
Bowel cancer risk higher for men with diabetes-(Reuters Health-05/07/2005) 
Hispanics, Blacks at Raised Colon Cancer Risk-(HealthDay News-27/06/2005)  
Western and Japanese diets up colon cancer risk-(Reuters Health-23/06/2005)  
Study advises cutting back on red meat: Heavy doses can add to risk of colon cancer -(Yahoo News-20/01/2005)  
Calcium Cuts Women's Colorectal Cancer Risk -Study-(Reuters-20/01/2005)  
Selenium May Reduce Colon Cancer Risk-(HealthDayNews-16/11/2004)
FDA Approves Wider Use for Sanofi Cancer Drug-(Reuters-07/11/2004)
Bowel cancer trials 'offer hope'-(Yahoo News-29/10/2004)
Doctors Advise Chemo Before Rectal Cancer Surgery-(Reuter News- 20/10/2004)
Obese Men More Prone to Colon Cancer-(Yahoo News-18/08/2004)
Clue to 'blocking' bowel cancer-(Yahoo News-18/08/2004)
Cancer Drug Warning Won't Change Its Use--(HealthDayNews-16/08/2004)
Researchers locate gene that promotes cancer growth-(Japan Times- 06/07/2004)
Milk May Lower Risk of Colorectal Cancer-(Yahoo News-06/07/2004)
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)
Calcium More Protective Against Some Polyps-(Yahoo News-15/06/2004)
Diseases share common lifestyle factors, study suggests-(Yahoo News-12/06/2004)
Drugs Improve Outlook for Colon Cancer Patients-(HealthDay News-02/06/2004)
Women's Preference for Women Physicians is a Barrier to Colorectal Cancer Screening-(AACR Annual Meeting)
Diabetes Mellitus is a Risk Factor for Colon Cancer: A Case Control Study -(AACR Annual Meeting)
Screening Can Cut Bowel Cancer Deaths-Scientist-(Reuters-18/05/2004)
Drug Route Doesn't Affect Colon Cancer Survival-(Reuters Health-18/05/2004)
Protein promotes cancer metastasis and survival-(Yahoo News-19/04/2004)
Baylor wins $1.3 million grant to study virus related to colon cancer-(Yahoo News-19/04/2004)
'Key-Hole' Surgery Appears Safe for Colorectal Cancer-(Reuters Health- 09/04/2004)
Currying Favor-(Health Sciences Institute e-Alert-04/03/2004)
FDA OKs First-Of-A-Kind Colon Cancer Drug-(ET-27/02/2004)
Hormone Use May Cut Colon Cancer Risk in Women-(Reuters Health- 03/03/2004)
More Evidence Vegetarian Diet May Cut Cancer Risk- (Reuters Health-16/02/2004)
Erbitux Lifts Hopes of Colon Cancer Patients-(Reuters-13/02/2004)
Colorectal Cancer: A Family Matter-(ET-10/02/2004)
High-carb diets may increase cancer risk-(USA TODAY-04/02/2004)
Catching the Culprit in Colon Cancer-(HealthDayNews-03/02/2004)             Heart Disease Marker Now Tied to Colon Cancer-(HealthDayNews-03/02/2004)
New Treatments Improve Outlook for Colorectal Cancer-(ET-12/01/2004)
Vitamin D Has Role in Colon Cancer Prevention-(ET-15/12/2003)
'Virtual' Colonoscopy Effective at Finding Polyps-(Reuters-02/12/2003)
Catching Colorectal Cancer in its Tracks-(HealthDayNews-02/12/2003)
Ginger Snaps Colon Cancer Growth in Mice-(HealthDayNews-28/10/2003)
Treatment Before Surgery Best for Rectal Cancer-(Reuters Health-21/10/2003) Aspirin Suppresses Cells That Lead to Colon Cancer-(Reuters Health-10/11/2003)
Hard Alcohol Ups Risk of Colon Cancer-(HealthDayNews-13/10/2003)
Over Time, Vitamins May Lower Colon Cancer Risk-(Reuters Health- 07/10/2003)
Chemotherapy Plus Radiation Best for Rectal Cancer-(Reuters Health- 17/09/2003)
Drinking doubles risk of colon cancer among men: report-(AFP-13/09/2003) Antigenics Says Cancer Vaccine May Extend Survival-(Reuters-18/08/2003)
Adjuvant 5-FU for Colorectal Cancer Does Not Benefit Patients with High-Frequency Microsatellite Instability-(ET-12/08/2003)
Testing for Colorectal Cancer: How Often Is Enough?-(HealthDayNews- 01/07/2003)
Obesity Worsens Women's Colon Cancer Prognosis-(HealthDayNews- 30/06/2003)
Nurses' Night Shifts Linked with Colon Cancer-(Reuters-03/06/2003)
Office Rectal Exam for Colorectal Cancer Doubted-(Reuters Health-20/05/2003)
Genentech: Colon Cancer Drug Extends Life-(Reuters-19/05/2003)
Big Eaters May Live Longer with Colorectal Cancer-(Reuters Health-13/05/2003)
Drinking May Cause Rectal Cancer, Scientists Say-(Reuters-12/05/2003) Studies Revive Colon Cancer Diet Theory-(AP-01/05/2003)
Cancer Strikes Blacks Harder than Whites-(HealthScoutNews-18/04/2003)
Treating One Cancer May Beget Another-(HealthScoutNews-17/04/2003)
Screening Interval for Colorectal Cancer Questioned-(HealthScoutNews- 15/04/2003)
Bowel Cancer Screening Could Save Lives: Experts-(Reuters-31/03/2003)
Blood Test May Predict Colon Cancer Risk-(Reuters Health-13/03/2003)
Colorectal Cancer: A Potential Killer That Can Be Beaten-(HealthScoutNews- 12/03/2003)
New Mutation In Colorectal Cancer Gene Reported-(ET-28/02/2003)
Western Diet Ups Colon Cancer Risk in Women-(Reuters Health-11/02/03)
Traveler's Diarrhea Bug May Help Treat Colon Cancer-(Reuters Health-10/02/03)

Know the Risks for Colorectal Cancer-(HealthScoutNews-26/01/03)
Blood Sausage May Hinder Colon Cancer Testing-(Reuters Health-20/12/2002)
New Link to Colon Cancer Found (HealthScoutNews-02/12/2002)

Unstable Chromosomes Could Kick Off Colon Cancer-(Reuters Health- 18/11/2002)
Common Virus May be Linked to Colorectal Cancer-HealthScoutNews- 15/11/2002)
Fiber Overload Won't Stop Recurring Colon Polyps-(HealthScoutNews- 05/11/2002)                                                                                             
New Tests May Detect Early Signs of Cancers-(Reuters-29/10/2002)
Women Should Start Colon Cancer Screening at 50 (Reuters Health-21/10/2002)
One Bad Copy of Gene Boosts Colon Cancer Risk-(Reuters Health-20/09/2002)
Radiation Alone Can Treat Rectal Cancer (HealthScoutNews-06/09/2002)
Scientists Find Clue to Bowel Cancer Survival (Reuters Health-03/09/2002)
New Pain Meds Treat Spread of Colon Cancer in Mice (Reuters Health-15/08/2002)
Eloxatin to Treat Colon Cancer (HealthScoutNews-13/08/2002)
Scientists Find New Clues About How Cancer Spreads (Reuters-05/08/2002)  Super side effects (Daily News-04/08/2002)
Growth Hormone Tied to Colon Cancer (HealthScoutNews-25/07/2002)
Folate Supplement May Reduce Colon Cancer Risk (Reuters Health-18/07/2002)

More Aggressive Colon Cancer Screening Urged (HealthScoutNews-15/07/2002)
Keyhole Surgery Better for Colon Cancer-Study-(Reuters-28/06/2002)
Veggies Slow Spread--Not Start--Of Colon Cancer-(Reuters Health-21/06/2002)  New Stool-Based Colorectal Cancer Screen Promising-(Reuters Health- 31/05/2002)
Vitamin D's Cancer Protection Explained (Reuters Health-16/05/2002)
Pope Helps Launch Global Anti-Cancer Effort-(Reuters Health-25/03/2002)       Value of UK Cancer Evaluation Rule Questioned-(Reuters Health-19/03/2002)
Calcium May Cut Risk of Colon Cancer-(HealthScoutNews-10/03/2002)
New test to detect colorectal cancer early-(Times of India Online-27/01/2002)

Researchers caution on colon surgery-(Times of India Online-16/01/2002)
Study Okays chemo for elderly –(Times of India Online-12/10/2001)
Popular test misses 76% of colon tumors: Study-(Times of India Online- 23/08/2001)
FDA approves camera-in-a-pill –(Times of India Online-03/08/2001)

MedImmune Searching for a Winner-(Cancer Info-17/07/2001)
Toxin that slows colon cancer growth-(Times of India Online-09/07/2001)

Study links processed meat to cancer-(Times of India Online-24/06/2001)
Tests on cancer drug suspended-(Times of Online-19/05/2001)
New vaccine promising in fight against colon cancer-(Times of India Online-16/05/2001)
Doctors encouraged by experimental cancer drug-(Times of India Online-14/05/2001)

Contraceptive pill may be answer for bowel cancer-(Times of India-17/04/2001)    Age and gender influence colon cancer risk-(Times of India Online-15/04/2001)
Bowel cancer risk 'may be inherited'-(Cancer Info-04/04/2001)
Ursodiol may lower risk of colon cancer in ulcerative colitis patients at high risk-(Cancer Info-17/01/2001)
Aphton to Commence Colorectal Cancer Clinical Trial in Us with Patients Who Have Failed Approved Chemotherapy-(Cancer Info-10/12/2000)
Colon Cancer Screening-(Times of India-22/11/2000)
Tale of two bugs: One causes cancer, one kills it-(Cancer Info-29/10/2000)
Olive oil may protect against colon cancer-(Times of India-20/09/2000)

Protein may block colon, rectal cancer-(Times of India-25/08/2000)
Intestinal Cancer-(Times of India-22/08/2000)
Thalidomide May Ease Diarrhea Caused by Chemotherapy-(Cancer Info-12/08/2000)
Colorectal cancer-(Times of India-01/08/2000)
Colorectal cancer - (Times of India-26/06/2000)
Efficacy of barium test in colon cancer doubted - (Times of India-17/06/2000)
Hepatic Arterial Infusion of Chemotherapy for Metastatic Colorectal Cancer-(Cancer Info-18/05/00)
FDA Approves Camptosar (Irinotecan Hydrochloride) In Combo Therapy For Metastatic Colorectal Cancer-(Cancer Info-26/04/2000)
New test for colon cancer-(Cancer Info-28/03/00)
Everything You Need to Know about Colon Cancer and How to Prevent It-(Time Europe-20/03/00)
FDA advisors give nod to cancer drug-(Cancer Info-16/03/00)

Doctors develop blood test for colorectal cancer - (Medivision- 15-31 December)
The Colon Checkup (Time-25/10/99)

[Top]

Antigenics Says Cancer Vaccine May Extend Survival-(Reuters-18/08/2003)

Biotechnology company Antigenics Inc said that its experimental cancer vaccine improved survival in 52 percent of advanced colon cancer patients who responded to the drug in a small mid-stage clinical trial. Antigenics, based in New York, said all of the 15 patients who responded immunologically to the vaccine, called Oncophage, were alive two years after treatment, compared with 50 percent of the 14 patients who did not respond. The disease-free survival rate was 51 percent for responders and 8 percent for non-responders. Typically, patients with advanced colon cancer can expect to live for up to a year, said Garo Armen, chief executive of Antigenics. "These results are not randomized, but in all the patients who showed an immune response, there has been a trend toward benefit in our clinical trials," he said.

Oncophage is a personalized vaccine derived from an individual patient's tumor. Because the injected drug contains the patient's own genetic codes, it is believed to be more effective in reprogramming the immune system to attack the cancer without side effects. The vaccine is being studied in a range of cancers, including kidney, pancreatic, skin and gastric cancers. The first pivotal-stage data on Oncophage is expected later this year with preliminary results from a Phase 3 kidney cancer trial, Armen said. In that study, patients who have had their cancer surgically removed are either being treated with the vaccine or simply observed, which is the standard of care for patients with that stage of kidney cancer, the CEO explained.

Initial results will be compiled when 80 to 100 of the 600 or so participants have had their cancer return, Armen said. Patients who do relapse are then offered chemotherapy drugs or other toxic therapies. If the results are promising, Antigenics would expect to file for U.S. Food and Drug Administration approval of the vaccine in 2004, he added. "We are encouraged with the collective data -- all pointing to the fact that there may be efficacy," Armen said. Data from the 29-patient colon cancer study was published in the Aug. 15 issue of Clinical Cancer Research.

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Adjuvant 5-FU for Colorectal Cancer Does Not Benefit Patients with High-Frequency Microsatellite Instability-(ET-12/08/2003)

According to results recently published in The New England Journal of Medicine, a genetic mutation known as microsatellite instability affects responses to the chemotherapy agent 5-fluorouracil (5-FU) in the adjuvant treatment of colorectal cancer. Particularly, patients with high-frequency microsatellite instability do not appear to derive any benefit from adjuvant treatment with 5-FU. Colorectal cancer is the fourth most commonly diagnosed cancer and the second leading cause of cancer deaths in the United States.

The colon and rectum are parts of the body's digestive system and together form a long, muscular tube called the large intestine. The colon is the first 6 feet of the large intestine and the rectum is the last 8-10 inches. If colorectal cancer is diagnosed in early stages, prior to the spread of cancer from its site of origin, cure rates are high following the surgical removal of the cancer. However, even at early diagnosis, some patients remain at a high risk of experiencing a cancer recurrence, as some undetectable cancer cells may remain in the body following surgery. Therefore, many patients are offered chemotherapy following surgery (adjuvant chemotherapy) in an attempt to kill any remaining cancer cells. Adjuvant chemotherapy optimizes a patients chance for a cure. Cancers contain different genetic mutations and researchers are now realizing that different genetic variables affect how a cancer will respond to various therapies.

Microsatellite instability (MSI) is a type of genetic mutation that occurs in approximately 15% of patients with colorectal cancer. Patients with this mutation can have a high degree (high frequency) of MSI or a low degree (low frequency) of MSI. Patients with no detectable MSI mutation are referred to as microsatellite stable. Researchers determine the presence of MSI by taking cells collected from the cancer and processing them with a laboratory test called polymerase chain reaction (PCR) that is able to detect specific genetic mutations. As determined through laboratory processes in tests involving the mixing of cancer cells and specific agents, 5-FU does not appear to have anti-cancer activity in colorectal cancer cells expressing high-frequency MSI mutations. However, other chemotherapy agents, such as those known as topoisomerase inhibitors, have demonstrated the capacity to kill colorectal cancer cells with high-frequency MSI.

At present, standard adjuvant therapy for colorectal cancer involves the use of the chemotherapy agent 5-fluorouracil (5-FU). However, newer chemotherapy agents have demonstrated anti-cancer activity in colorectal cancer and are currently used in the treatment of more advanced colorectal cancers or are being evaluated in clinical trials. As research involving genetics and associated responses to treatment matures, standard practice will undoubtedly become more individualized, enabling physicians to provide specific treatment regimens matched with a patients genetic mutation(s) to ensure optimal outcomes.

Researchers from several institutions recently conducted a study in an attempt to determine if patients with MSI responded differently to fluorouracil-based chemotherapy. This study evaluated the outcomes of patients who had been diagnosed with stages II-III colorectal cancer and had been participants in 5 clinical trials between 1978 and 1988. All of these trials were direct comparisons of adjuvant chemotherapy with 5-FU and leucovorin or levamisole, versus no adjuvant therapy following surgery. From these data involving 570 patients, frozen specimens of their cancer were tested through PCR; 17% had high-frequency MSI, 10.5 had low-frequency MSI and nearly 73% were microsatellite stable. Patients with low-frequency MSI or those who were microsatellite stable had an improved cancer-free and overall survival when treated with 5-FU-based therapy, compared to no adjuvant therapy. Conversely, patients with high-frequency MSI derived no benefit in terms of cancer-free and overall survival following treatment with 5-FU-based adjuvant therapy, and even showed a slight decrease in survival when treated with 5-FU-based chemotherapy, compared to no adjuvant therapy. For all patients not treated with adjuvant chemotherapy, those with high-frequency MSI had an improved long-term cancer-free and overall survival, compared to those with low-frequency MSI or those who were microsatellite stable.

The researchers concluded that patients with stages II and III colorectal cancer with high-frequency MSI do not benefit from 5-FU-based adjuvant chemotherapy. These results are consistent with laboratory results demonstrating that 5-FU does not have anti-cancer activity in colorectal cancer cells with high-frequency MSI. However, other chemotherapy agents that demonstrate the capacity to kill colorectal cancer cells with high-frequency MSI in the laboratory may be effective as adjuvant therapy in this group of patients. The researchers caution that further clinical trials evaluating this issue are necessary to confirm these results and possibly change the standard of practice involving adjuvant chemotherapy in patients with stages II and III colorectal cancer.

[Top]

Testing for Colorectal Cancer: How Often Is Enough?-(HealthDayNews-01/07/2003)

Two new studies come to very different conclusions on the proper timetable for having sigmoidoscopy, the uncomfortable but effective test to screen for cancer of the colon and rectum. American health officials currently recommend that healthy people have a sigmoidoscopy every five years. But a just-released study says there is, perhaps, a 1-in-100 chance that someone who tested negative will develop a cancer, or an intestinal growth that leads to cancer, within three years of the last exam. Yet another study, using completely different methods, found that a single sigmoidoscopy reduced the risk of undetected cancer for as long as 15 years, suggesting the length of time between tests could be extended.Sigmoidoscopy is the insertion of a flexible tube to inspect the lower portion of the colon, where 60 percent of all colorectal cancers occur. The tube allows doctors to look for polyps -- growths that can become cancerous. Most people who have a sigmoidoscopy must take an enema, and there is a slight risk that the intestine may be damaged.

The first study, done by Dr. Robert E. Schoen and colleagues at the University of Pittsburgh Cancer Institute, included 11,583 people who had an initial sigmoidoscopy and 9,317 who had a second examination three years later. Of the second group, 1,292 of the people were found to have some sort of intestinal growth in the second examination, says a report in the July 2 Journal of the American Medical Association. Follow-up exams of 951 of the people revealed that 72 had a precancerous polyp, and six had a cancer. "Although the overall percentage with detected abnormalities is modest, these data raise concern about the impact of a prolonged screening interval after a negative examination," the researchers write in the journal.

The other study, led by Polly A. Newcomb, director of prevention at the Fred Hutchinson Cancer Research Institute in Seattle, collected information on screening history and colorectal risk factors from 1,668 cancer patients and 1,294 healthy people. There was a four-fold reduction in the incidence of cancer in the distal region of the colon -- the part inspected during sigmoidoscopy -- for people who recalled having at least one sigmoidoscopy, compared to those who said they never had one. The reduction in cancer lasted for at least 15 years, says the report in a recent issue of the Journal of the National Cancer Institute. The University of Pittsburgh's Schoen says the second study's conclusion is open to question because it relied on potentially unreliable self-reporting to determine who had had sigmoidoscopies. But Newcomb says "we have found that people can accurately report if they have had a sigmoidoscopy." Newcomb says her study argues for lengthening the recommended period between sigmoidoscopies. It takes a long time for most polyps to become cancerous, she says. "The five-year period recommended by organizations such as the American Cancer Society doesn't appear to be data-based, unlike other recommendations," she contends.

Schoen, who is an associate professor of medicine and epidemiology at the Pittsburgh center, says he is not proposing a change in the five-year recommendation "at this time." "We need more data," Schoen says, adding he'd like to see what the cancer rate was five years after the first screening. "Maybe it's not that different." Because of issues such as "cost, complications, capacity [to do the testing], I don't think the results of [his] paper should be interpreted as saying that everyone has to come back in three years," Schoen says. But "it does look like the more screening, the less the chance of missing something," he says.

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Obesity Worsens Women's Colon Cancer Prognosis-(HealthDayNews-30/06/2003)

Obesity raises the risk of death from colon cancer in women, but not men. That's the surprising conclusion of a new study that found female colon cancer patients can expect a much worse outcome if they're heavy, and perhaps even a greater chance their tumors will return. But the study, reported in the August issue of Cancer, found no such association in men, whose outcomes were unaffected by their weight. Previous studies have found obesity's impact on developing colon cancer and dying from it is stronger in men than in women, says Eugenia Calle, an epidemiologist at the American Cancer Society. "It's one of the most consistently observed gender differences," Calle adds. However, the latest work focused on people who'd already been diagnosed with colon tumors, not the incidence of the disease in the general population, which could help explain the difference. What's not in dispute is the overall connection between weight and cancer.

Earlier this year, Calle and her colleagues reported that overweight and obesity could account for as many as one in seven cancer deaths among men, and one in five among women, each year in the United States. Being overweight increases blood levels of certain hormones and proteins, such as estrogen and insulin, which can stimulate tumors. Weight affects the risk of cancers in both sex-neutral organs, such as the esophagus, colon, liver and gallbladder, as well as sex-specific sites such as the breast, ovaries, cervix in women and the prostate gland in men.

In the latest study, Dr. Jeffrey Meyerhardt, of the Dana-Farber Cancer Institute in Boston, and his colleagues looked at the link between body mass index -- a ratio of height and weight -- and colon cancer in 3,759 men and women who'd been diagnosed with the disease. All the patients were enrolled in a clinical trial of a now-common drug taken after surgery to reduce the risk of relapse. Obese women -- those with a BMI was at least 30 -- were about a third more likely than their normal-weight peers to die within roughly nine years of starting the study. They also appeared to be somewhat more likely to suffer relapses of their cancer, although the study wasn't large enough to prove that. Weight wasn't a factor in survival or return tumors for men, the researchers found.

For patients of either gender, being overweight did seem to provide at least one benefit. Obese patients were less likely than their thinner counterparts to suffer serious side effects from their chemotherapy. Although many cancer drugs are given in proportion to a patient's "ideal" weight, the doses in the latest study were based on actual weight. The results therefore suggest "that we should be treating patients doses based on their actual body weight," Meyerhardt says. It's possible, he adds, that the fewer side effects in the overweight patients is a signal that higher doses of cancer drugs could be used safely and with better results.

Previous research has hinted that women who gain significant amounts of weight in the year after being diagnosed with breast cancer face a worse prognosis than those who stay the same weight. Researchers at Dana-Farber are now looking at whether the same phenomenon occurs in colon cancer patients. Colorectal cancer will be diagnosed in more than 147,000 Americans this year, and more than 57,000 will die from the disease, according to the American Cancer Society.

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Nurses' Night Shifts Linked with Colon Cancer-(Reuters-03/06/2003)

Sunshine may be good for you, and nurses who work regular night shifts have a higher risk of colon cancer, U.S. researchers reported. The study by researchers at Harvard Medical School and Brigham and Women's Hospital in Boston supports earlier research that found women who work night shifts have a higher risk of breast cancer. "Because night-shift work has become very common in developed countries, future studies should assess the relationship of light exposure to the risk of other cancers and consider the risks in men," they wrote in their report, published in the Journal of the National Cancer Institute.

The U.S. Bureau of Labor Statistics estimates that about four percent of adults work rotating night shifts. Shift work disrupts normal melatonin production and increases levels of other hormones such as estrogen. Women's cancers are often linked with estrogen, but Dr. Eva Schernhammer, who led the study, said melatonin may play a more important role. "While this finding needs to be replicated in future studies, the data is beginning to show that it may be melatonin, not estrogen, that is influencing cancer risk," she said in a statement. "If melatonin's anti-cancer properties are the source of our observed effects, this research opens a whole new arena of potential associations between exposure to light and a variety of cancers."

The researchers studied 78,586 women taking part in a long-running program called the Nurses' Health Study. The nurses who worked night shifts at least three times a month for 15 years or more had a 35 percent greater risk of colon or rectal cancer. Melatonin is produced at night and regular exposure to sunlight affects the production cycle, which peaks in the middle of the night. Artificial light suppresses melatonin production. "Melatonin has well established anticarcinogenic properties, and a link between exposure at night and cancer risk through the melatonin pathway could offer one plausible explanation for the increased risk we observed," the researchers wrote. They noted, however, that they could be missing something and urged further study.

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Genentech: Colon Cancer Drug Extends Life-(Reuters-19/05/2003)

Genentech Inc. said its experimental colon cancer drug, Avastin, extends life far longer than it had expected, marking one of the biggest recent breakthroughs in cancer research. Results of a late-stage trial show that the drug, which slows tumor growth by cutting the supply of blood and oxygen, improved survival when used in combination with chemotherapy. The news surprised analysts and scientists, who had become skeptical of the approach, known as anti-angiogenisis, after the drug had failed to prove effective in treating breast cancer.

"Showing a survival benefit is very rare," said Meirav Chovav, an analyst at UBS Warburg. "This is going to transform the treatment of solid tumors, and it's obviously going to transform Genentech." Avastin is the first of a new class of drugs to treat cancer by inhibiting a protein known as vascular endothelial growth factor, which plays an important role in stimulating the growth of new blood vessels to tumors. By slowing the tumor's growth, Avastin appears to help chemotherapy do its work of destroying malignant cells. "This will give a huge boost to the anti-angiogenisis field, which many scientific journals have been questioning lately," said Sapna Srivastava, an analyst at ThinkEquity Partners.

Genentech said the main side effect of Avastin is an increase in hypertension, or high blood pressure. The company said there is also an increase in tearing of the gastrointestinal tract. The company said this is uncommon. Patients with colon cancer live on average 14 months from the time of diagnosis. Genentech said it met the main goal of its trial, which analysts said would likely be an extension of life by about two months. Since the results are beyond Genentech's expectations, analysts said the drug could extend life by about four months.

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Office Rectal Exam for Colorectal Cancer Doubted-(Reuters Health-20/05/2003)

It's an unpopular procedure for patients and doctors alike, and new research suggests that office-based digital rectal exams aimed at detecting colorectal cancers may not even be useful in spotting disease. Instead, researchers advise skipping the in-office rectal examination, waiting instead for a more thorough exam at the time of colonoscopy. "Now that colonoscopy is routinely available, I think it's reasonable -- and I think many doctors are actually already doing this -- not to stick with routine rectal examination in the office," said Dr. Louise Langmead of the University of Sydney Concord Hospital in Australia. She presented the findings here at Digestive Disease Week, the largest annual gathering of gastroenterologists in the world.

In a digital rectal exam, a gloved physician uses a finger to try to detect suspicious growths in a non-sedated patient. While the procedure is usually painless, for most patients "it's not a comfortable procedure -- it's undignified," Langmead said in an interview with Reuters Health. Usually, patients with symptoms suggestive of colorectal cancer will also receive a digital rectal exam at the time of their colonoscopy, when they are under sedation. When questioned, most of the patients in Langmead's study said that, if given a choice, they would much prefer undergoing the digital exam at that time, rather than while wide awake in their doctor's office.

So how useful is the in-office rectal exam? In their study, Langmead and her colleagues looked at the location of tumors in 68 patients with colonoscopy-confirmed rectal cancers. One limitation of the digital rectal exam is that "it is dependent on the length of the person's finger who performs it," Langmead said. Her team judged the length of the average index finger to be roughly 7 centimeters (about 2.75 inches). Looking over the medical records of the 68 patients, the researchers found that cancers in a full 45 were located beyond that 7-centimeter range, meaning they would most likely have been missed during a digital exam. Furthermore, factors such as the presence of stool in the rectum mean that the test is generally assumed to have about a 75 percent detection rate. All this means that, according to the researchers' calculations, physicians would have to perform "280 rectal examinations to detect one cancer," Langmead said. "And this is in patients who are going to have a rectal examination at the time of their colonoscopy anyway." She points out there are no official guidelines dictating that doctors perform these exams when looking for colorectal cancers -- just "conventional wisdom" stemming from a period before the advent of colonoscopy and other high-tech diagnostic tools. "I think patients could be asked their opinion on it -- would they like to have it now or would they like to wait until colonoscopy?," she said. "So my recommendation would really be 'ask the patient'."

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Drinking May Cause Rectal Cancer, Scientists Say-(Reuters-12/05/2003)

Drinking large quantities of alcohol may increase the risk of rectal cancer, although wine appears to be less of a threat than beer or spirits, scientists said. "Regular drinkers significantly increase their risk of rectal cancer, but that risk is reduced if wine makes up a third or more of weekly consumption," researchers from the National Institute of Public Health, in Copenhagen, Denmark said. People who had more than 14 drinks per week of beer and spirits, but no wine, were 3.5 times as likely to suffer rectal cancer as non-drinkers, they wrote in the journal Gut. Those who drank just as much alcohol, but a third of it in the form of wine, had a much smaller increase in their risk.

The authors said the benevolent effect of wine might be due to wine drinkers having a healthier lifestyle, but it may also be because of a chemical found in grapes that could protect against cancer. Previous research shows that a chemical called resveratrol, found in grapes and wine, inhibits tumor growth. The authors found no link between alcohol and cancer of the colon, and said it was not clear why alcohol might cause cancer in the rectum but not the colon. The authors could not be certain why alcohol might cause rectal cancer, but suggested drinks could be contaminated with cancer-causing compounds during production, or drinking may damage the liver, inhibiting the breakdown of carcinogens. The findings are based on a study which assessed weekly smoking and drinking habits of 15,491 men and 13,641 women aged 23-95 years old. The researchers also examined other risk factors for colorectal cancer and followed up their patients after 15 years. According to the World Health Organisation (WHO), colorectal cancer is one of the most common cancers worldwide and accounts for 940,000 new cases every year and 500,000 deaths. The WHO suggests eating less meat but more fruit and vegetables can reduce the risk of colorectal cancer.

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Big Eaters May Live Longer with Colorectal Cancer-(Reuters Health-13/05/2003)

Despite the dangers associated with a high-calorie diet, new research that people who eat more calories live longer after a colorectal cancer diagnosis than light eaters. However, eating a high-calorie diet has also been linked to a higher risk of developing colorectal cancer in the first place, according to study author Dr. Marie-Christine Boutron-Ruault. Although the reasons behind these seemingly contradictory findings are not clear, Boutron-Ruault said that she and her colleagues suspect that people who develop colorectal cancer as a result of eating a high-calorie diet may have a form of the disease that is less deadly than people who have cancer as a result of other causes. "The main hypothesis is that the cancer due to this particular risk factor -- here, high energy intake -- has a lesser malignant potential than cancers due to other causes," Boutron-Ruault, based at the Institute for Food and Nutrition in Paris, France, told Reuters Health.

Since so much remains unknown, Boutron-Ruault cautioned that people should not interpret these results to mean that eating too many calories is healthy, even if they have colorectal or other cancers. "I would say that getting a cancer is certainly not a good thing and that there are many studies leading to the conclusion that high energy (intake) increases the risk of cancer. It is too early to know if once the patient has got a cancer, it is beneficial to have a high-energy diet," she said.

Colorectal cancer is the second-deadliest form of the disease in the U.S., and only approximately 45 percent of patients are alive five years after being diagnosed. To determine whether calorie intake influences survival time, Boutron-Ruault and her colleagues looked at an earlier study that recorded 148 patients' eating habits during the year before they were diagnosed with colorectal cancer. The researchers then followed up with the patients about 10 years after they underwent surgery. Reporting in the journal Gut, the researchers found that people who ate the most calories -- from carbohydrates, protein, or fat -- were more than 80 percent more likely to be alive five years after a cancer diagnosis than people who ate the least amount of calories. Boutron-Ruault noted in an interview that whether patients were obese had no influence on their risk of dying. "Our findings do not encourage (patients) to be obese to better survive colorectal cancer," she said. "What we hope will be the main consequence of our findings is that medical doctors, especially oncologists, take some interest in the nutritional status and the diet of their patients," Boutron-Ruault said. She added that more research is needed to investigate the relationship between post-diagnosis diet and cancer prognosis.

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Studies Revive Colon Cancer Diet Theory-(AP-01/05/2003)

New research has revived the notion that a high-fiber diet may protect against colon cancer. Long-standing recommendations for high-fiber diets have taken a hit over the last few years after a handful of carefully conducted studies failed to find a benefit. But experts say two major studies published in The Lancet medical journal - one on Americans and the other on Europeans - indicate previous research may not have examined a broad enough range of fiber consumption or a wide enough variety of fiber sources to show an effect. "These two new findings show that the fiber hypothesis is still alive," said the leader of the American study, Ulrike Peters of the U.S. National Cancer Institute.

Figuring out the relationship between nutrition and disease has always proved difficult, but experts say fiber is particularly complicated because there are various types and they all could act differently. Fiber is found in fruits, vegetables and whole grains. Americans eat about 16 grams a day, while Europeans eat about 22 grams. The new studies indicate fiber intake needs to be about 30 grams a day to protect against colon cancer. There are 2 grams of fiber in a slice of whole meal bread. A banana has 3 grams and an apple has 3.5 grams, the same as a cup of brown rice. Some super-high fiber breakfast cereals have as much as 14 grams per half cup.

In the American study, investigators compared the daily fiber intake of 3,600 people who had precancerous growths in the colon with that of around 34,000 people who did not. They were divided into five groups, according to how much fiber they ate. The average roughage intake in the lowest group was 12 grams a day, while in the highest group it was 36 grams a day. People who ate the most fiber had a 27 percent lower risk of precancerous growths than those who ate the least. In the European study, the largest one ever conducted on nutrition and cancer, scientists examined the link in more than 500,000 people in 10 countries. As in the American study, questionnaires separated the people into five groups, according to fiber intake. Following them for an average of four years, 1,065 of them had developed colorectal cancer. Those who ate the most fiber, about 35 grams a day, had about a 40 percent lower risk of colorectal cancer compared with those who ate the least, about 15 grams a day, the study found."In the top quintile (group) they were eating 15 grams of cereal fiber, which is equivalent to five or six slices of whole meal bread, plus they were eating seven portions of fruit and vegetables a day, which is basically the Mediterranean levels," said the study's leader, Sheila Bingham, head of the diet and cancer group at Cambridge University's human nutrition unit.

Discussions about the link between fiber and bowel health - or, at least the relative merits of white and brown bread - date back to antiquity. In a twist on modern thought, Hippocrates, who lived in the 5th century B.C., believed white bread was more nutritious because it creates less feces than brown bread. Scientists now believe the extra feces is a benefit. The contemporary theory that fiber wards off colon cancer began in the 1970s, when a British doctor, Denis Burkitt, noted that poor people in Africa produce more feces than Westerners and get much less colon cancer. One obvious difference between the two groups was that Africans consumed more fiber. Scientists believe that fiber dilutes and absorbs cancer-causing agents and makes them flow more quickly through the body. Researchers have also theorized that a high-fiber diet makes protective changes to cells or curtails bile acids that irritate the intestinal lining and promote growths.

The first big dent in the theory came in 1999 from a study that tracked the eating habits of 88,757 American nurses for 16 years. The risk of colon cancer was the same, regardless of how much fiber the women were eating. Then in 2000, two studies which used a different method also came up negative. They put people on different diets and counted precancerous growths in their colons for up to four years. There was no apparent effect from high-fiber diets or supplements. One major difference between the former and current studies is that the new ones examine more diverse populations who eat different types of fiber and in hugely varying amounts. However, Andy Ness, a lecturer in epidemiology at Bristol University in England, who was not connected with either study, said the latest research is not the last word. "Across Europe, there is an amazing variation in risks of cancer. There is also a huge variation in diet, so across these cultures you can get this breadth of intake. However, what you might be picking up across this range of diet is a range of cultures. It's possible it's something else that goes with that pattern of diet," he said.

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Cancer Strikes Blacks Harder than Whites-(HealthScoutNews-18/04/2003)

Despite a substantial decrease in cancer among blacks over the last decade, this racial group still has consistently higher rates of almost all cancers than do whites, and their death rates are higher. Statistics comparing incidences of colon, prostate, lung and breast cancers, the most common cancers for both whites and blacks, show the latter group's chances of developing certain types of cancer -- as well as dying from them -- are much higher than whites, says Dr. Mark Clanton, first national vice president of the national board of the American Cancer Society. "Prostate cancer occurs in African-American men 60 percent more often than in white men, and they die from it 1.3 times more often, and African-American women have a 20 percent higher incidence rate of colon cancer and a 40 percent higher mortality rate than do white women of the same ages," Clanton says.

Further, while the incidence of lung cancer among black men has decreased 1.6 percent annually since 1995, their chances of contracting lung cancer are still 50 percent higher compared to the risk to white men. These are among the sobering statistics released by the American Cancer Society in its latest report on the incidence of cancer among the 37 million Americans of black and Hispanic descent in the United States. The report is published in conjunction with National Minority Cancer Awareness Week. "Even without new advances in treatment and diagnosis of cancers, if we can engineer among African-Americans a similar reduced rate of cancer as that of whites, then tens of thousands of lives would be saved," Clanton says.

Dr. Harry Harper, an oncologist at the Hackensack University Hospital Medical Center, says oncologists are very aware of this discrepancy in cancer incidence. "This information is out there among oncologists, but we haven't really taken a global approach to the problem," he says. "This report provides very helpful information so we can take the knowledge and start to use it to reach out to the communities that haven't shared in the benefits of cancer research and treatment." The report is not all bad news. The overall incidence of cancer and mortality from the disease has dropped by 1.2 percent a year since 1993 for blacks. For black men, in fact, the drop in cancer rates was more than for white men during that same period, 2.1 percent a year versus 1.4 percent for white men. For black women, there has been a 0.4 percent drop annually since 1991, compared to a 0.8 percent drop for white women.

Also, five-year survival rates have also improved for blacks, more black women are getting regular mammograms -- 67 percent now compared to only 30 percent 10 years ago -- and black men, though not women, are smoking less. But these improvements still leave a huge gap between cancer rates for blacks and whites, Clanton says, who points to economic disparities and lifestyle differences between the two groups. While blacks make up only 12 percent of the population, they account for a third of the poor in this country, the report states. Twelve percent of blacks have no health insurance, Clanton says, "which means they have considerably less access to screening and prevention advice." Difficulty in geographical access to health care and less education about the importance of early screening for cancers are also factors, leading to later diagnoses of illness and thus lower rates of survival from cancers, Clanton says. "Further, health-related behavior may predispose African-Americans to increased cancer risk, with smoking and exercise rates being the most important," Clanton says. "Exercise is emerging as a powerful way to reduce cancer, diabetes and heart disease."

While smoking rates between the two ethnic groups are not too dissimilar, black men and women have lower rates of exercise than do whites -- 48 percent of whites report engaging in regular, sustained exercise compared to 39 percent of blacks. In addition, blacks are heavier. In 2000, 77 percent of black women were overweight, a jump from 59 percent in 1962. They also have a higher rate of obesity than do whites -- 30 percent versus 20 percent, according to the U.S. Centers for Disease Control and Prevention. Obesity is associated with an increased risk for diabetes, heart disease and several types of cancer including those of the breast, colon, uterus and esophagus. Clanton says that focus on disparities in cancer incidences between racial and ethnic groups is beginning to get the attention it deserves. "The National Institutes of Health is creating a major focus on studying and trying to understand these disparities," he says. "We have to equalize the progress and improve the progress for the whole population."

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Treating One Cancer May Beget Another-(HealthScoutNews-17/04/2003)

The molecular action of a drug used to treat colon cancer might cause cancer in other tissues, researchers report. That discovery calls for caution in the search for other anticancer drugs with the same action, but it is no cause for immediate concern, says Rudolf Jaenisch, a professor of biology at the Massachusetts Institute of Technology's Whitehead Institute for Biomedical Research. Jaenisch is the leader of the group reporting the finding in Science. The drug is 5-azadeoxycytidine. It fights colon cancer by reducing the activity of a simple molecule, methane, in the cancer cells. Intricate animal studies now show this process, hypomethylation, can cause leukemia, the journal paper says. Methane consists of one atom of carbon and four atoms of hydrogen. It is found in a vast number of organic chemicals, such as methyl alcohol. Inside a living cell, methyl molecules attach themselves to DNA, the genetic molecule, turning genes off or on. "It has been known for 30 years that cancer cells are hypomethylated, but it has not been known whether this is cause or effect," Jaenisch says. "We show that it is causal."

The discovery is important because several drug companies are searching for drugs that use the same mechanism as 5-azadeoxycytidine, which is very toxic, Jaenisch says. The new drawback could affect the use of such a drug, when and if it is found, he says. The finding was years in the making. It started with a long effort by François Gaudet, a graduate student in the lab, to develop a strain of mice with abnormal hypomethylation. When that effort succeeded, it was found that 80 percent of those mice developed an aggressive form of leukemia, which originates in the thymus. Amir Eden, a postdoctoral fellow, then showed that hypomethylation speeded the development of other forms of cancer in mice engineered to have those tumors. "There seems to be a selective advantage for tumors to be hypomethylated, because their chromosomes are more unstable," Jaenisch says.

It's a fascinating discovery, says Dr. Stephen Baylin, a professor of medicine in the Johns Hopkins University Oncology Center, but no reason to lose one's head. "This is not something we should ignore, something to think about, but I would caution against any suggestion that this would be a problem in treating cancer," Baylin says. One important reason is the finding was made in very young mice that were altered as embryos, he says. "The study of tumors very early in the lifespan is very different from blocking tumors later in adult life," he says. "We can't extrapolate these results to what they would mean for treating cancers in adults, and probably in children." Jaenisch plans to look at hypomethylation in other cancers, such as those of the pancreas, breast and liver. Studying metabolic differences in those tumors could lead to a better understanding of tumor formation, he says.

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Screening Interval for Colorectal Cancer Questioned-(HealthScoutNews-15/04/2003)

A new study questions the recommended guidelines for a common colorectal cancer screening procedure, and suggests the current five-year screening interval may be excessive. The benefits of the procedure, called a sigmoidoscopy, can last as long as 10 or even 15 years, the study researchers say. Almost 1 million cases of colorectal cancer are diagnosed worldwide each year. Several effective tests are available that can detect the disease in its earliest and most treatable stages, but little is known about how often patients over 50 should undergo these screenings. Previous studies have shown that precancerous tissue, called polyps, can take up to 15 years to progress to cancer, suggesting that screening may not be necessary as often as every five years. Researchers from the Fred Hutchinson Cancer Research Center in Seattle looked at the efficacy of sigmoidoscopy screening -- a procedure where a scope is used to examine the lower part of the large bowel -- in reducing the incidence of colorectal cancer. They also asked the question: How often should this test be used for the greatest risk-to-benefit ratio?

The study examined the screening history and colorectal risk factors of 1,668 patients between the ages of 20 and 75 living in Washington state. The researchers compared the rate of colorectal cancer in this group to 1,294 healthy individuals within the same age range. The findings show those who had received a screening sigmoidoscopy had a fourfold reduction in the incidence of colorectal cancers compared with individuals who had never had the procedure. Moreover, this benefit appeared to be sustained for more than 15 years, indicating the recommended screening interval is too aggressive. "If screening by sigmoidoscopy every 10 years was widely adopted by adults over age 50, the incidence and mortality of colorectal cancer could be substantially reduced," says Polly Newcomb, a researcher at the Fred Hutchinson Cancer Research Center in Seattle and lead author of the study, which appears in the Journal of the National Cancer Institute.Patients don't like invasive screening procedures such as sigmoidoscopies and compliance is an ongoing problem for physicians. Moreover, if the screening was recommended once every 10 years, the reduction in usage would translate into significant savings for the health-care system, the researchers argue.

But Jack S. Mandel, chairman of epidemiology at Emory University's Rollins School of Public Health, says the structure of the study may undermine its findings. "There's a tendency for these types of studies to overstate the benefits. We're trying to understand the precise magnitude of the benefit [of sigmoidoscopy screening] and in this study there's uncertainty in that benefit," he says. The number of individuals involved in some of the study's analyses are so small that they could easily be distorted by a mistake or classification error. Moreover, says Mandel, the study looked at self-reported data that was not verified using patient records to ensure that the subjects had really undergone screening sigmoidoscopy. That bias tends not to be a problem because sigmoidoscopy isn't a procedure that a patient is likely to forget, Newcomb says. People rarely confuse it with other screening tests because the experience is unique from the other available options, she says. Mandel argues a decision to lengthen the recommended five-year sigmoidoscopy screening interval should be postponed until more accurate data are available from a large randomized control trial -- several of which are currently under way. Newcomb, however, cautions results from those studies are unlikely to be available for another 10 years. In the meantime, the results of studies like this one are the next best thing to a randomized control trial.

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Bowel Cancer Screening Could Save Lives: Experts-(Reuters-31/03/2003)

British medical experts predicted a sharp fall in deaths from bowel cancer by 2020 if the government introduces screening for the disease. "The biggest step forward in the next decade is likely to be screening -- as a result we will see the number of people dying from this disease fall dramatically," said Professor John Northover, one of Britain's top bowel cancer surgeons. He said better diagnostic techniques, including powerful "finger-printing" techniques will help doctors determine how a tumor will behave. "This will allow us to do smaller operations without chemotherapy or radiotherapy for the early low aggression tumors, while precisely targeting increasingly powerful drugs at the more high aggression tumors," Northover, of St. Mark's Hospital in London, added in a statement.

Bowel, or colorectal, cancer is the second most common cause of cancer deaths in men and women in Britain, but if the disease is diagnosed early, 80 percent can be successfully treated. Britain is considering introducing screening and is looking at two types of tests to detect the disease. One type of screen, fecal occult blood testing (FOBT), looks for blood in the stool. During the other test being considered, flexible sigmoidoscopy, a flexible probe with a camera on the end is used to look for benign growths that can turn into cancer in the lower part of the bowel. Two-thirds of all bowel cancers develop in this area. The government is analyzing results from trials of the two types of tests. A spokesman for the Department of Health said experts will be looking at which is the most clinically effective, cost effective and how they will be implemented. "There are a whole range of things that have to be decided," he told Reuters.

Dr. Wendy Atkin, who is also at St. Mark's Hospital, said if screening is introduced, the disease will be more treatable. "Currently only 40 percent of patients survive for more than five years," she said in a statement. The disease is more common in people 50 years and older. Bleeding from the rectum or blood in the stool, diarrhea or constipation lasting more than two weeks, pain, discomfort or a lump in the abdomen and unexplained tiredness are symptoms of the illness. The latest figures from the charity Cancer Research UK show that in 1999 there were 34,661 British cases of bowel cancer.

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Blood Test May Predict Colon Cancer Risk-(Reuters Health-13/03/2003)

A simple blood test that looks for a certain genetic alteration may identify people at risk of colorectal cancer, preliminary research suggests. The blood test, still in the experimental stages, does not detect colorectal cancer, but it may identify people who are likely to develop the disease and who would benefit from additional screening, the study's lead author told Reuters Health. "This is preliminary and needs to be confirmed by more research," said Dr. Andrew P. Feinberg. "But we hope that it will be possible to identify patients in the general population at risk of cancer before they develop cancer." In an interview, Feinberg, who is at Johns Hopkins University Medical School in Baltimore, Maryland, noted that "we have made much progress" in identifying people who are at risk of cardiovascular disease, such as those with high cholesterol. These people can be treated early, even before disease develops. "We hope eventually to do the same kind of thing for cancer," he said.

The new blood test may identify people who should undergo more frequent screening for colorectal cancer, according to Feinberg. On the other hand, he said, people who have a low risk may be able to be screened less often. But the researcher emphasized that "there is a lot of work that needs to be done" to show that a person who tests positive on the blood test is more likely to develop cancer in the future. He noted that the present study looked at the risk of past or present cancer, but not the risk of cancer in the future. And for the blood test to become practical, Feinberg said that it needs to be refined and made easier and cheaper to perform.

The test looks for "loss of imprinting" in the gene for a protein called insulin-like growth factor II (IGF2). Imprinting marks on DNA tell whether a gene came from the mother or the father. Previous research has shown that loss of imprinting in the IGF2 gene occurs in about 30% of people with colorectal cancer, compared with only 10% of people without the disease. To see whether the loss of imprinting in this gene could be used to identify people at risk of colorectal cancer, Feinberg used a DNA-based blood test to look for the alteration in 172 people who were undergoing the cancer screen colonoscopy. Loss of imprinting was much more common in people with a family history of colon cancer and those who had the disease themselves, Feinberg's team reports in the journal Science.

People with a family history of the disease were about five times more likely to have lost imprinting in the IGF2 gene. And people with a history of growths called adenomas, which can become cancerous, were more than three times more likely to have loss of imprinting than people with no history of the growths. Loss of imprinting was almost 22 times more common in people who had colorectal cancer or who'd had it in the past than in those with no personal history of the disease. The study is "a step toward the goal of developing a noninvasive test for detecting cancer," according to Dr. David F. Ransohoff of the University of North Carolina at Chapel Hill. In a related editorial, he, too, points out that the test does not look for cancer itself, but a person's "tendency" to develop cancer. If this test is sensitive enough, however, Ransohoff adds, it may be useful in identifying people who can forego conventional cancer screening because they have a low lifetime risk of colorectal cancer. Feinberg and a co-author are entitled to a percentage of any royalties that Johns Hopkins may receive through the sale of the technology used in the study. In addition, Feinberg is a paid consultant to the German biotech company Epigenomics AG, which has a licensing arrangement with the university.

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Colorectal Cancer: A Potential Killer That Can Be Beaten-(HealthScoutNews-12/03/2003)

Colorectal cancer is the second-leading cancer killer in the United States, claiming more than 57,000 lives every year. Yet, the vast majority of these deaths could be prevented. How? Through regular screening by a medical professional. Because March is National Colorectal Cancer Awareness Month, 50 organizations have joined forces to spread the message that screening measures -- plus a healthy lifestyle -- can help stop this killer in its tracks. "People are great procrastinators, [but] a screening test will help save your life," says Dr. Sidney Winawer, co-chairman of the International Digestive Cancer Alliance and a professor of medicine at Memorial Sloan-Kettering Cancer Center in New York City.

While lifestyle is important -- specifically, regular exercise combined with a balanced, healthy diet that includes plenty of fruits and vegetables and fewer animal fats -- screening is the proven key to prevention. Virtually all colorectal cancers start as polyps, or abnormal growths, so the key is to find the polyps before they turn malignant. "The National Polyp Study, an Italian study and a University of Minnesota study have shown that removing polyps prevents colon cancer," Winawer says. When it comes to spotting potentially dangerous polyps, the technique of choice is the colonoscopy, although other promising tools are under review. And Medicare now pays for colonoscopies, an indication of just how seriously the medical establishment is taking the issue of prevention and early diagnosis of colorectal cancer.

New guidelines issued in February by the U.S. Multisociety Task Force on Colorectal Cancer state that all men and women over age 50 who have no symptoms and no family history of colorectal cancer should have a colonoscopy. People with a family history need to be screened starting at an earlier age. The procedure, which usually takes half an hour and is done under mild sedation, involves the insertion of a long, flexible tube with a camera mounted on the end up through the rectum and on into the colon, or large intestine. The camera takes pictures and transmits them outside the body. Perhaps the best thing about a colonoscopy is that it's "one-stop shopping," says Winawer, lead author of the new guidelines. "You can do screening, diagnosis and treatment by removing the polyps all in one examination," he adds. The downside of the procedure is the preparation, which involves taking potent laxatives to make sure the colon is completely clear. "The preparation is not pleasant, but I think it's a small price to pay for one's life," Winawer says.

In the future, patients may benefit from a "virtual colonoscopy," the procedure newswoman Katie Couric underwent on the NBC "Today" show last March. Less invasive than a conventional colonoscopy, a virtual colonoscopy uses a computer assisted tomography (CAT) scanner to survey the colon from outside the body. However, a virtual colonoscopy requires the same preparation as a conventional colonoscopy, is not able to perform biopsies or remove polyps, and may or may not be as effective as the traditional treatment. "It's potentially promising, but we don't know how accurate it is yet," Winawer says.

Another promising screening method under investigation is DNA testing that hunts for genetic mutations in stool samples that might indicate the presence of cancer or precancerous growths. "Right now, the pick-up rate [for spotting cancerous polyps] is about 50 percent and it's a very complex laboratory assay that's required," Winawer says. "It's not generally available nor is it approved for general screening use." Taking a chapter from Fantastic Voyage, researchers have also developed a tiny capsule containing a camera. The capsule is swallowed as if it were a regular pill, then the camera takes pictures as it travels through the digestive tract. The video transmittals are relayed to doctors viewing a computer monitor on the outside. The procedure is only FDA approved for the small intestine, which is located above the large intestine. "It works well for the small bowel [small intestine], but it doesn't work well for the colon [large intestine]," says Dr. David Beck, chairman of the department of colon and rectal surgery at the Ochsner Clinic Foundation in New Orleans. "It's not as good a picture of the colon as the scope."

Again, the miniature camera would not be able to perform a biopsy or remove a troublesome growth. "You'd have to go back in, but that may be a way to see who really needs a colonoscopy," says Dr. Michael Bouvet, a surgical oncologist at the Rebecca and John Moores University of California San Diego Cancer Center. "These are all not ready for prime time."

There have also been advances even when screening does detect cancer. Surgery to remove cancerous portions of the colon or rectum is still the primary treatment. "If the cancer is caught early, it's very curable," Beck says. "If the tumor is more advanced, we may add some additional things like radiation or chemotherapy." If a tumor is found in the rectum, physicians will often do chemotherapy to shrink the tumor before surgically removing it. This is in an effort to preserve the sphincter at the entrance of the rectum so the patient can continue with normal bowel movements, Bouvet says. "The big message really is: Please don't wait for something like this down the road," Winawer says. "Save your life today by going in for a screening test that's available today."

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New Mutation In Colorectal Cancer Gene Reported-(ET-28/02/2003)

A newly discovered gene mutation that causes colorectal polyps and cancer has been described in the New England Journal of Medicine (Vol.348, Number 9; 791-799). Although this is not a common mutation, its discovery is another step forward in learning why some people develop this cancer.Almost all researchers agree that most colorectal cancers begin as benign polyps that slowly transform into cancer. They think this process takes about 10 years. Most of these polyps and cancers occur in people with no evidence of a gene mutation. But, about 5 to 10% of colorectal cancers are caused by known gene mutations.

There are two major types of mutations. In the most common kind, called HNPCC, a person forms a few polyps, which are benign growths. One or more of these goes on to become cancer. The second kind of gene mutation is due to a malfunction in the APC gene. People with mutations in this gene form hundreds of polyps that inevitably transform into cancer. They must be treated by removal of their entire colon. But many times, patients, along with their family members, will have many polyps in their colon but no gene abnormality can be found. It was these people who formed the basis of this study. Oliver Sieber, BSc., Lara Lipton, MB, BS, and their colleagues at the London Research Institute and in other European countries, examined the genetic makeup of patients who had no known gene abnormality but had multiple polyps. Some of them had developed cancer. One group was comprised of people with fewer than 100 polyps, which is far less than APC gene mutation carriers. A second group had more than 100 polyps, so they appeared as if they might have an APC gene mutation, but didn't.

The researchers found that about 30% of people who had more than 15 polyps but less than 100 had a mutation in a gene called MYH. Of the people with more than 100 polyps, 7.5% had a mutation in this gene. All these people carried the mutation in both copies of the gene. A mutation may not cause any problem if it occurs on only one copy of the gene. This kind of mutation is called recessive. The researchers estimated that about 1% of us carry a mutation on the MYH gene, but because we also have a normal MYH gene we don't develop cancer - or do we? The researchers say that they can't be sure that having even one copy of the mutation may not make someone more susceptible to developing polyps and colorectal cancer. But according to them, only studies of large numbers of people can answer this question.

Colorectal cancer is the third most common cancer for men and women in the US (excluding non-melanoma skin cancers) and the second leading cause of cancer deaths. Nearly 150,000 people will be diagnosed with this cancer in 2003 and 57,000 people will die from it. Only lung cancer causes more cancer-related deaths in the US.

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Western Diet Ups Colon Cancer Risk in Women-(Reuters Health-11/02/03)

A large new study has found that eating a diet rich in fruits and vegetables may cut a woman's risk for colon cancer. However, the investigation found no tie between diet and rectal cancer risk. Previous research has suggested that diet plays a significant role in colon cancer, the third most common cancer in the US, according to the American Cancer Society Web site. The ACS estimates that about 105,500 new cases of colon cancer and 42,000 new cases of rectal cancer will be diagnosed this year. Dr. Teresa Fung of the Harvard School of Public Health in Boston and colleagues analyzed dietary patterns and the development of colorectal cancer in 76,402 women aged 38 to 63 who were participating in the Nurses' Health Study.

During the 12-year follow-up period, 445 of the women developed colon cancer and 101 developed rectal cancer, the researchers note in the Archives of Internal Medicine. Women who ate more processed and red meats, soda, sweets, refined breads and high-fat dairy products-what the researchers termed a "Western" diet--had a 46% increased risk for developing colon cancer, compared to women who were consuming the least amount of foods associated with a Western diet. Women who ate more foods that characterized a "prudent" diet, including fruits, vegetables, whole grain products, poultry and fish, were less likely to develop colon cancer, but the relationship was not statistically significant. The study also did not identify a relationship between diet and rectal cancer. "Our study provides further evidence that switching from a typical Western diet to a more prudent diet may reduce the risk of colon cancer," Fung and colleagues conclude.

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Traveler's Diarrhea Bug May Help Treat Colon Cancer-(Reuters Health-10/02/03)

A toxin released by the bacteria that cause traveler's diarrhea and chronic diarrhea in developing countries may also slow the growth of colorectal cancer, researchers said. The protective effect of the toxin from the E. coli bacterium responsible for traveler's diarrhea may explain why rates of colorectal cancer are lowest in countries with the highest rates of infection with the bacteria, Dr. Stephen Carrithers of the University of Kentucky in Lexington told Reuters Health. During the study, the researchers used the toxin to slow the growth of a sample of laboratory-grown colorectal cancer cells originally taken from a human patient. Eventually, doctors may be able to use this bacterial toxin, known as ST, to treat or even prevent colon cancer in patients, according to study author Dr. Scott A. Waldman of Thomas Jefferson University in Philadelphia.

Waldman told Reuters Health in an interview that small doses of the E. coli toxin ST-- along with medications to prevent diarrhea--could help control the spread of colorectal cancer cells in patients with cancer that has spread throughout the body. Even if patients have only small polyps inside their colons, he said, ST could help shrink those polyps, or perhaps even prevent colorectal cancer in people who are at risk of the disease. "You can block diarrhea, but still have the anti-proliferative effects. So that's important," study author Dr. GianMario Pitari, also of Thomas Jefferson University, told Reuters Health.

ST likely protects against colon cancer only while it is inside the body, the authors noted--which suggests that people who suffered one bout of traveler's diarrhea while abroad are no longer enjoying the anti-cancer benefits of the toxin. Waldman added that the ST appears to only curb the spread of colorectal cancer, so patients whose cancers are advanced enough to spread to other parts of their bodies would likely have to use other chemotherapy treatments as well. "This doesn't kill the cells, it just makes them slow down," Waldman noted. Waldman and Pitari, along with researchers at the Mayo Clinic in Rochester, Minnesota, published their findings in the early edition of the journal Proceedings of the National Academy of Sciences.

According to Waldman, ST slows cancer growth by binding to a protein on the surface of cancer cells. This stimulates the production of a substance that in turn allows calcium to enter into the cell. The influx of calcium effectively stops the cell from dividing. He added that the role of calcium in this mechanism could help explain the observation that people who take calcium have a lower risk of developing colorectal cancer. E. coli is present in the US and other countries besides those marked by chronic diarrhea, Waldman said. However, only certain strains of E. coli carry the genetic material needed to produce the particular ST featured in the current report, he added. Carrithers, who wrote a commentary accompanying the study, told Reuters Health that previous research has suggested that this ST may also kill colorectal cancer cells--not just slow them down. This suggests that this treatment could eventually even rid some patients of the disease, he said. He added that he agreed that the ST toxin holds promise for the treatment of colorectal cancer, and is likely one that patients will embrace if it is shown to be safe and effective in humans. "If the sacrifice is for one to have occasional diarrhea yet prevent the (tumors) in the colon from ever forming or progressing, it's worth it," Carrithers said.

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Know the Risks for Colorectal Cancer-(HealthScoutNews-26/01/03)

Colorectal cancer -- or cancer that begins in either the colon or the rectum -- is the second-leading cancer killer in the United States. Like so many cancers, this disease has both a genetic and a lifestyle component. Here are some common risk factors: · If you have parents or siblings who have had colorectal cancer, you are more likely to develop it yourself. · Women who have had ovarian, uterine or breast cancer are also at a higher risk, as are men and women who have already had colorectal cancer. · Although research continues into possible behavioral factors, diets that are high in fat and calories and low in fiber seem to be likely culprits. · The disease is much more common in people over the age of 50.

The good news is that the disease is almost entirely preventable. Most colon or rectal cancers start as small polyps, or benign growths on the inner wall of the colon and rectum. Detecting and removing these polyps soon after they appear can prevent most cases of colorectal cancer. Talk to your doctor about a regular screening program. In general, the American Cancer Society recommends that screening start at age 50. People have different options, but the one preferred by the cancer society is a fecal occult blood test (FOBT) once a year and flexible sigmoidoscopy every five years. You could also opt to have a colonoscopy every 10 years. A sigmoidoscope is a lighted tube about the thickness of a finger that's inserted into the lower colon via the rectum. A colonoscope is basically a longer sigmoidoscope.

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Blood Sausage May Hinder Colon Cancer Testing-(Reuters Health-20/12/2002)

People with a hankering for black pudding should abstain while they're being screened for colorectal cancer, British researchers advise, as the congealed pig's blood in the British delicacy can interfere with screening tests used to identify blood in the stool. In the British Medical Journal's holiday issue, traditionally a repository of the more entertaining sort of evidence-based medicine, Dr. Neil Haslam and colleagues conducted a rigorous study into the effect of eating blood sausage on fecal occult blood testing, also called Haemoccult testing. They conducted their study in Bury, "black pudding capital of the world," although they note that variations on the blood sausage theme are also served in Germany, France and Spain.

The British version is made of congealed pigs' blood, fat, and rusks, or sweetened bread crusts, contained in a piece of intestine. The 10 participants under the age of 35 completed a Haemoccult test, requiring six stool samples taken over three consecutive days. "Participants then eagerly ate a locally produced 7-ounce black pudding and then had a further Haemoccult test," they write. A positive test result was defined as the occurrence of one or more positive specimens from the six provided.

Initially all volunteers returned negative tests, but after consumption of black pudding, four people tested positive. The researchers then questioned 100 people about their black pudding consumption and found that 63% succumbed on occasions, 8% weekly. In Bury, the numbers eating the "almost irresistible" delicacy would mean a doubling of the proportion of people who would test positive for fecal occult blood, the researchers calculate. "Gourmets should be advised to avoid black pudding during screening for fecal occult blood," they conclude. The research team reports no external funding, however they do note under the heading of competing interests: "NH is extremely fond of black pudding".

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Fiber Overload Won't Stop Recurring Colon Polyps-(HealthScoutNews-05/11/2002)

Don't toss your All-Bran yet, but new research shows that fiber intake did not affect the recurrence rate of colon polyps. All the participants entering the trial were already consuming higher-than-average amounts of fiber, however, which may have skewed the results. "Because they were already consuming fiber, they may already have been protected," says Elizabeth Jacobs, lead author of the study appearing in the Journal of the National Cancer Institute.

Colon cancer, the second biggest cancer killer in the United States, starts with tiny polyps in the colon. Plenty of evidence suggests that the cancer is at least partially caused by environmental factors. And anecdotal evidence suggests that high-fiber diets may protect against the cancer. This research examined data from the Wheat Bran Fiber (WBF) trial, which looked at about 1,500 men and women in the Phoenix area, all of whom had had at least one colorectal adenoma removed within the past three months. Adenomas or adenomatous polyps are abnormal growths in the colon that are generally thought to be precursors to cancer. The participants had been randomly assigned to receive a cereal fiber supplement of either two grams per day or 13.5 grams a day. After three years, there appeared to be no difference in recurrence rates between the two groups.

The participants were then divided into four groups according to how much fiber they were eating when they joined the trial. Here, again, baseline fiber intake did not affect adenoma recurrence between the groups or within the groups. Nor did the source of dietary fiber (fruits; breads, cereals and crackers; and vegetables) at baseline seem to have any effect on polyp recurrence. It's difficult to draw any firm conclusions from the results because the men and women studied were already consuming more fiber than your average American (17.5 grams per day vs. 14.8 grams per day). "This only represents three years and since the participants already may have eaten more fiber, all we know is that three years of supplementation did not work," Jacobs says.

"In the world of polyps, three years is probably not long enough, biologically, to expect any real results," says Dr. Irwin Grosman, chief of gastroenterology at Long Island College Hospital in Brooklyn, N.Y. The ideal study, Jacobs adds, would look at what people eat through their entire lives, because it takes at least 10 to 20 years for colorectal cancer to develop. Such a study, however, is unlikely to occur. Another important area for research is to determine where intake is most important: for prevention or to slow down growth rates of the polyps. Still, Jacobs says, none of this means you should stop eating fiber, especially given that it seems to have beneficial effects on other aspects of health, such as heart disease and diabetes.

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Unstable Chromosomes Could Kick Off Colon Cancer-(Reuters Health-18/11/2002)

A mutation in a gene called APC is believed to be present in most cases of colorectal cancer, but new research raises the possibility that a defective APC gene may not be the first step on the road to cancer. According to a mathematical model created by Dr. Christoph Lengauer of Johns Hopkins University in Baltimore, Maryland and colleagues, it is possible that unstable chromosomes may trigger changes in the APC gene that lead to cancer. In an interview with Reuters Health, Lengauer stressed that the idea is only a possibility and still needs to be proven. What comes first, APC mutations or chromosomal instability, is a bit a "chicken or the egg" question, he said. Unlike that age-old question, though, determining whether changes in APC or unstable chromosomes come first could have important implications for cancer therapy, according to Lengauer. Documenting the first step in colorectal cancer, he said, will give scientists a target for developing new treatments to destroy cancer in its earliest stages, before it has a chance to spread.

In the interview, Lengauer explained that about 85% of the time, the APC gene is defective in colorectal cancer. This gene helps regulate the growth of cells, so if it is not working properly, cancer cells can grow unchecked. Most cases of colorectal cancer also involve another type of chromosomal defect, Lengauer said, in which the rate at which chromosomes are lost and gained is increased. The Johns Hopkins researcher noted, however, that it has been uncertain whether this chromosomal instability is a result of an APC mutation or itself triggers such a genetic defect. The question still awaits a conclusive answer, but it is possible that chromosomal instability could come first, Lengauer's team asserts in a report in the journal Proceedings of the National Academy of Sciences. The authors developed a mathematical model suggesting that genetic mutations that cause chromosomal instability could develop before APC mutation occurs.

To develop new therapies for colorectal cancer, it is important to know what the earliest steps in the cancer process are, Lengauer said. If changes in APC come first, then it might be possible to develop a drug to prevent those changes, he said. Alternately, a drug that keeps chromosomes stable might stave off cancer if chromosomal instability is the initial step in colorectal cancer, according to Lengauer. The model does not prove that chromosomal instability is the first step, but it does give researchers a starting point, he said. To see if unstable chromosomes are indeed the "driving force" behind colorectal cancer, Lengauer and his colleagues plan to look for chromosomal instability in the earliest forms of precancerous growths called adenomas. Finding chromosomal instability in these growths would support the idea that chromosomal instability is the instigator of colorectal cancer, he said.

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Common Virus May be Linked to Colorectal Cancer-HealthScoutNews-15/11/2002)

A virus that lurks harmlessly in the bodies of tens of millions of Americans may play a role in the development of colorectal cancer, new research suggests. The findings are preliminary, and the germ -- known as human cytomegalovirus -- might not actually contribute to the development of the second deadliest type of cancer, says study co-author Dr. Charles S. Cobbs, a neurosurgeon at the Birmingham VA Medical Center in Alabama. "But if other people can confirm this data, then the plot thickens," he says.

Colorectal cancer is "notoriously difficult to treat," Cobbs says, especially if it spreads to other organs such as the liver. An estimated 148,300 cases will be diagnosed this year, and the disease will kill approximately 56,600 Americans, according to the American Cancer Society. Among all cancers, only lung cancer takes more lives. Colorectal cancer typically strikes people over the age of 50. Screening tests are available, and experts estimate that they could detect and prevent 90 percent of the cases. Cobbs says his investigation into colorectal cancer was inspired by his previous research into the possible role that human cytomegalovirus (CMV) could play in brain tumors.

CMV is a type of herpes virus, a member of the same family of germs that cause cold sores, genital herpes, chicken pox, some kinds of mononucleosis and Epstein-Barr virus. An estimated 40 percent of the U.S. population has been infected with CMV, says Frank Myers, an epidemiologist with Scripps Mercy Hospital in San Diego. However, except for infants, who can be especially vulnerable, the virus almost never causes symptoms. "It's thought to lie around latent in the body and not do anything," Cobbs says. The exceptions are people with weak immune systems, such as AIDS patients, and those who are on special drugs because of organ transplants. CMV is extremely common in Third World countries, where close to 100 percent of the population may be infected. The virus is transmitted through saliva and urine, Myers says. Breastfeeding can transmit the disease, says Cobbs, and so can sex. Gay men are especially at high risk.

In his previous research, Cobbs found signs of CMV in almost every brain tumor he examined. Studies from the 19