Bladder Cancer

Vitamins Don't Curb Bladder Cancer Risk-(Reuters Health-12/10/2003)

A few reports have suggested that certain vitamins protect against bladder cancer. However, new research indicates that the apparent anti-cancer effect disappears after accounting for a person's smoking history. In the current study, people with high levels of vitamins in their blood had a low risk of bladder cancer. As it turns out, however, these people were also the ones who rarely, if ever, smoked. Because smoking is a well-known risk factor for bladder cancer, it was probably their lack of smoking, not the high vitamin levels, that protected these people from cancer.

The results, which are published in The Journal of Urology, are based on a study of 9345 men who had blood samples frozen when the study began and then were followed for more than 20 years to determine the rate of bladder cancer. During the study period, 111 men developed bladder cancer. The stored blood samples from these men and from 111 similar men without cancer were analyzed for several vitamins. Dr. Abraham M. Y. Nomura, from Kuakini Medical Center in Honolulu, and colleagues found that as blood levels of alpha-carotene, beta-carotene, lutein plus zeaxanthin, beta-cryptoxanthin, and total carotenoids rose, the risk of bladder cancer decreased. However, after accounting for how much a person smoked, none of the vitamin levels had much of an effect on bladder cancer risk, the team found.

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Selenium May Cut Bladder Cancer Risk in Ex-Smokers- (HealthScoutNews-01/11/2002)

If you're a former smoker and want to protect yourself against bladder cancer, you might want to include selenium-rich foods in your diet. A new study, published in Cancer Epidemiology, Biomarkers and Prevention, found that ex-smokers who had high levels of selenium had a decreased risk of bladder cancer. This effect didn't hold true for current smokers or non-smokers. The study authors suggest this is because non-smokers have not exposed their bodies to the same oxidative stress that former smokers have, and current smokers are overwhelming any positive effects from selenium due to the toxic chemicals found in tobacco.

Selenium is an essential trace mineral and antioxidant. It helps keep the immune system and the thyroid gland working properly. It is found in plant foods, meat, fish, cereal, dairy products, eggs and some nuts, particularly Brazil nuts. The selenium content of food varies, depending on how much selenium is present in the soil the food is grown in. Selenium deficiency is unusual in the United States, but not so in other parts of the world. In places such as China and Russia, where the selenium content of the soil is low, selenium deficiency is more common. The recommended daily intake of selenium is around 55 micrograms. Doses higher than 400 micrograms daily could lead to side effects such as gastrointestinal problems, hair loss and mild nerve damage, according to the National Institutes of Health. More than 50,000 Americans are diagnosed with bladder cancer every year, according to the National Cancer Institute. Worldwide, about 200,000 new cases occur annually, reports the study. Those at greatest risk for the disease include smokers, males, people over 40, whites and people who work with chemicals.

For the new study, researchers in the Netherlands studied data on more than 3,000 men and women who had participated in the larger Netherlands Cohort Study. The average age of the study volunteers was between 55 and 69 at the start of the study. Just over 400 of those studied developed bladder cancer during the six years of research. All of the participants completed a questionnaire that helped the researchers assess and control for other possible cancer risk factors, such as alcohol use, diet, chemical exposure and a family history of bladder cancer. The volunteers also provided a toenail clipping, because analysis of toenail clippings gave the researchers an estimate of the average selenium intake during a year. People who had at least 30 percent more selenium in their toenails had a slightly decreased risk of bladder cancer. However, the decrease in risk was greatest for ex-smokers. The researchers also found that higher selenium levels only seemed to affect invasive forms of bladder cancer. None of the other known antioxidants, such as vitamin C, E and beta carotene, appeared to have any effect on bladder cancer rates in the study.

Commenting on the study, nutritionist Samantha Heller of New York University Medical Center says one possible reason smokers don't seem to get any benefit from selenium is that smoking might be depleting the mineral in their bodies. She adds that if you want to prevent bladder and other cancers, supplementing with selenium isn't the answer. "All of these healthy things work together as a team," Heller explains. So, if you supplement with selenium and a couple of other vitamins, you could still be missing out on essential nutrients. The key, she says, is keeping everything in balance. That means stop smoking and start eating a balanced diet that includes lots of vegetables, nuts and legumes, Heller says. The authors of the study conclude that more research needs to be done, and they don't recommend taking selenium supplements until more conclusive proof of its benefits is available.

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Arsenic in Water Tied to Bladder Cancer Mutations-(Reuters Health-20/11/2002)

High arsenic levels in drinking water are already thought to raise the risk of bladder cancer, and now research suggests that heavy arsenic exposure may also cause bladder tumors to be more aggressive. The study of bladder cancer patients in Argentina and Chile found that those whose drinking water contained high levels of arsenic tended to have more chromosome abnormalities in their tumors. These genetic alterations were also associated with later-stage and more-quickly growing tumors, according to findings published in the Journal of the National Cancer Institute. All of this suggests that bladder tumors in people with high arsenic exposure "may behave more aggressively" than those of patients with lower exposure, report Dr. Lee E. Moore, of the National Cancer Institute in Bethesda, Maryland, and her colleagues.

A naturally occurring element found in the earth's crust, arsenic is released into water sources when rocks, minerals and soils erode. People are typically exposed to arsenic through water or food, but exposure can also come from industrial waste. High arsenic exposure has been linked to elevated risks of several cancers, including those of the bladder, kidneys, liver and lungs. In the current study, Moore's team examined tumor samples from 123 patients who had been exposed to arsenic in their drinking water. Participants were separated into four groups according to their 5 years of highest arsenic exposure. In the lowest-exposure category, patients had yearly been exposed to less than 10 micrograms per liter (mcg/L) of water--the new standard that has been adopted in the US, set to take effect in 2006. In the next-lowest group, exposure was between 10 and 99 mcg/L; the current US standard calls for arsenic levels of no more than 50 mcg/L.

Moore's team found that the average number of chromosome abnormalities per tumor went up in tandem with patients' arsenic exposure. For those in the two lower-exposure groups, there were five to six alterations per tumor, on average. Patients with the highest arsenic exposure--at least 300 mcg/L each year--showed nine chromosome alterations per tumor, on average. According to the researchers, these findings suggest that higher arsenic exposure causes greater "genetic instability" in bladder tumors, possibly by disrupting the normal capacity of body cells to manage the DNA damage that causes cancer. This, they note, could both boost the rate of bladder cancer development, and--if the current findings are an indication--lead to bladder tumors that are more aggressive and deadly.

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Bladder Cancer and Smoking Link Studied-(HealthScoutNews-05/10/2002)

Researchers at the UCLA's Jonsson Cancer Center recently launched a wide-ranging study on ways to prevent smoking-related bladder cancer. The $5.9-million program has a number of objectives. They include: development of biomarker tests to help predict who will get bladder cancer; discovering the molecular profile of the disease to identify people who are most at risk; a clinical trial of green tea extract and the experimental drug Iressa to determine how effective they are in bladder cancer prevention; and creation of a tumor bank to assist research into bladder cancer.

The five-year effort is funded by a grant from the National Cancer Institute and is the largest prevention study in the United States to focus on bladder cancer in current and former smokers. Smoking is a major risk factor for bladder cancer, says the project's principal investigator, Dr. Arie Belldegrun, chief of the cancer center's urologic oncology division. "We will study innovative approaches to reduce the risk of bladder cancer. And while we'll study prevention in patients who already have bladder cancer, our goal is to develop effective prevention strategies for people who may be at risk, but who do not yet have bladder cancer," Belldegrun says. This year, health estimates predict there will be 56,500 cases of bladder cancer diagnosed in the United States and 12,600 people will die from it.

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Urine Test May Catch Bladder Cancer Early (Reuters Health-17/07/2002)

A urine test for a cancer-linked protein may be better at catching bladder cancer than standard urine testing, UK researchers report. Although it is too early to say what role the test might have in diagnosing bladder cancer, the study authors say their findings show it is "highly predictive" of the disease. Dr. Kai Stoeber of University College London and his colleagues report the findings in the Journal of the National Cancer Institute. Stoeber was with the University of Cambridge at the time of the study.

Right now, urine tests for bladder cancer involve looking for abnormal cells, a method called cytology. While cytology is good at catching high-grade tumors--those with lots of abnormal cells that are likely to spread quickly--it is able to spot far fewer low-grade bladder cancers. Cystoscopy, in which a thin scope is threaded into the bladder, is the "gold standard" test for bladder cancer. However, Stoeber and his colleagues note, it is invasive and costly, and many patients with vague urinary symptoms may needlessly undergo the procedure.

Their new urine test looks for levels of a protein called minichromosome maintenance 5, or Mcm5. Mcm5 belongs to a family of proteins important in initiating the replication of DNA. Stoeber's team had previously found that cancerous epithelial cells--thin layers of cells that line the organs--show an abnormal expression of proteins in this family. In this study, of 353 patients with possible bladder cancer symptoms, the Mcm5 test caught up to 92% of new or recurrent cases of the disease. However, it also produced false-positives 22% of the time, according to the report. Still, at this level of accuracy, Stoeber and his colleagues note, the test could help spot patients with early, low-grade bladder cancer. In addition, they say, it shows promise for catching higher-grade tumors, as well.

"The test detects bladder cancers of all stages and grades, including those often missed by urine cytology," the authors write. "One of the most important results of this work is that the protein test can establish early diagnosis of bladder cancer," Stoeber said in a statement released by Cancer Research UK. And although the study was aimed at bladder cancer, Stoeber's team found another potential benefit of the Mcm5 test: Twelve study participants who turned out to have prostate cancer ( news - web sites) also showed elevated levels of the protein in their urine. According to the researchers, this suggests the "potential applicability" of the test to other types of cancer.

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New arsenic study pressures EPA-(Times of India Online-14/09/2001)

A National Academy of Sciences report shows that the Environmental Protection Agency has greatly underestimated the cancer risks of arsenic in drinking water, according to EPA officials and other environmental experts familiar with the report. The report being issued to EPA Administrator Christie Whitman this week, which has been kept under wraps, says the cancer risks are much higher than the agency had previously acknowledged under the Clinton and Bush administrations. For the first time, the Bush EPA is conceding it will be hard-pressed not to accept arsenic standards for drinking water at least as stringent as those adopted by the Clinton administration but put on hold by the Bush administration.

``This makes it more difficult,'' Whitman spokeswoman Tina Kreisher. ``Their study reinforces the cancer risks. ... If anything, they believe that there is more risk than the EPA thought previously.'' In particular, the 189-page report reinforces that the cancer risks are high even for low levels of arsenic in tap water. The current standard of 50 parts per billion of arsenic in drinking water has been in place since 1942. Arsenic is both a naturally occurring substance and industrial byproduct, entering the water supply from natural deposits and pollution. It is found at high concentrations in Western mining states and other areas heavy with coal-burning and copper smelting.

One of former President Clinton's last actions, three days before leaving office in January, was to adopt a tougher standard of 10 ppb, but the Bush administration suspended that, citing the high costs to local communities of implementing that standard and calling for additional study while questioning the scientific basis for the Clinton rule. The standard was suspended until next February, leaving in place at least for the time being the 50 ppb arsenic standard. The Bush administration had said the EPA lacked evidence to justify the $200 million annual cost to municipalities, states and industry of meeting the Clinton standard by 2006. Whitman also had convened an EPA working group to study costs to local communities.

Now, however, the academy report says that even at 3 ppb, the risk of bladder and lung cancer is between four and 10 cancer deaths per 10,000 people, according to one person who's seen the report. The EPA's maximum acceptable level of risk for the past two decades for all drinking water contaminants has been one in 10,000. While the report makes no recommendations more specific than that the standard should be set lower than 50 ppb, its authors studied the health effects of establishing a standard of 3, 5, 10 or 20 ppb — as was requested by Whitman. At each level, the study found, the cancer risks were much higher than the EPA had estimated. The report points to health effects other than cancer that should be considered, including heart disease, high blood pressure and diabetes. It also rejects arguments by industry and some local water utilities that there is a clear, safe threshold below which arsenic does not cause cancer.

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Chemotherapy before surgery doubles bladder cancer survival-(Times of India Online-16/05/2001)

The typical survival of victims of early but advancing bladder cancer nearly doubles to six years when doctors treat them first with chemotherapy rather than relying solely on surgery, as is now standard. The research is the latest to support the trend of shrinking cancer with drugs before attempting to remove it. The strategy is now sometimes attempted for a variety of tumours, including breast, colon and oesophageal cancer, though the improvement in survival ordinarily amounts to a few months. An estimated 54,000 Americans are diagnosed with bladder cancer annually, and 12,500 die from the disease. The study was conducted on people with what doctors call locally advanced disease - cancer that had grown into the muscular wall of the bladder but has not clearly spread beyond. Nevertheless, even though the tumour cannot be seen outside the bladder, microscopic bits of cancer often have already escaped. In the United States, an estimated 18,000 to 20,000 cases are discovered at this stage each year.

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'Acceptable' levels of arsenic linked to cancer-(Times of India Online)

As US regulators work toward lowering arsenic levels in drinking water, a new study from Taiwan shows that levels currently considered ''acceptable'' can increase cancer risk. Earlier this year, the US Environmental Protection Agency (EPA) issued a ruling that called for maximum allowable arsenic levels to be lowered from 50 parts per billion (PPB) to 10 PPB in an effort to cut the health risks associated with the contaminant. The new EPA administrator is reviewing that ruling, due to take effect in 2002.

Now, researchers report that arsenic levels between 10 PPB and 50 PPB in drinking water increase a person's risk for developing bladder cancer. They looked at the occurrence of cancers affecting the bladder, kidney and urinary tract among 8,102 residents of northeastern Taiwan, as well as their level of exposure to arsenic in drinking water. The risk of urinary cancer increased as exposure to arsenic increased, the investigators found. Exposure to arsenic levels between 10.1 PPB to 50 PPB in drinking water nearly doubled cancer risk compared to the risk in the general population. Risk was roughly eight times higher when levels were between 50 PPB and 100 PPB and 15 times higher for people exposed to arsenic levels exceeding 100 PPB. Arsenic is found naturally in rocks, soil, water and air. Industrial, agricultural or mining operations can also cause arsenic contamination in the surrounding environment. Scientists say that most water sources in the United States contain less than 5 ppb of arsenic, but there may be hot spots with higher than the predicted occurrence.

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Urine Test may help Diagnose Bladder Cancer-(Reuters Health-30/12/1999)

Two compounds found in urine of bladder cancer patients could be the basis for a new, non-invasive test for bladder cancer, according to researchers. The finding could ``improve traditional methods of bladder cancer surveillance,'' concludes Dr. Thomas Stanisic of Affiliated Urology Specialists in Peoria, Illinois. His comments come in response to a study published in the December issue of the Journal of Urology. Bladder cancer is the fourth leading cancer in men, and the eighth leading cancer in women, affecting over 54,000 Americans every year. Patients suspected of having bladder cancer are usually referred for an invasive procedure where tissue is removed from the bladder lining and then examined under the microscope. Researchers have long sought a non-invasive test for bladder cancer that might ease the way to routine screening and earlier detection.

Investigating this possibility, Spanish researchers led by Dr. Marta Sanchez-Carbayo of the Hospital General Universitario de Alicante, compared levels of CYFRA 21-1 and NMP22 -- two compounds found in urine -- in a group of 267 adults. About two thirds of the subjects were either currently battling bladder cancer or had a previous history of the disease, while one-third were either healthy or suffered from some other, non-cancerous form of bladder illness. According to the investigators, NMP22 and CYFRA 21-1 urine tests correctly detected 75.7% and 83.8% of bladder cancers, respectively. Using the two markers in combination, researchers were able to accurately spot nearly 90% of bladder cancers.

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