CANSA Research Highlights Issue 40 17 March 2009
Freckles, Moles may indicate risk for eye cancer
People with moles and other features that put them at higher risk of skin cancer may also have an increased chance of developing melanoma of the eye, a new study says.
Canadian researchers found links between skin moles, freckles, moles on the iris and risk of uveal melanoma — cancer of the eye’s iris, ciliary body or choroid. Among the findings were that people with atypical moles (ones that appear different in shape or color from common moles) had almost three times the risk of having uveal melanoma as did those without such moles.
The research, published in the March issue of Ophthalmology, might help clarify a long-unclear issue. Previous studies have been mixed about whether moles and freckles indicate a higher uveal melanoma rate.
“Our study points to an interaction of genetic susceptibility and an environmental insult in the form of UV exposure,” Dr. Ezekiel Weis, of the University of Alberta’s ophthalmology department and leader of the study, said in an American Academy of Ophthalmology news release. Weis’s team believes the analysis they performed on previous studies adjusted for factors that might have skewed earlier results.
Each year, about six people in a million develop uveal melanoma, the most common non-skin melanoma in the United States. People age 70 or older with light skin and eye color and who are prone to sunburn most often develop the condition, according to earlier research by Weis. Treatment is available, but the mortality rate remains high.
Combo of Tests Might Spot Ovarian Cancer Early
Used together, a blood test and an ultrasound scan may be effective in detecting ovarian cancer in its early and more curable stages, British researchers report.
The two-step detection method could become a new standard in the fight against this deadly and hard to spot malignancy, experts say.
“It appears to be an approach that may be workable,” said Robert Smith, director of cancer screening at the American Cancer Society.
The report was published in the March 10 online edition of The Lancet Oncology.
Experts note that, when found early, ovarian cancer is 90 percent curable. But early detection is often impossible, because the disease causes few or no symptoms as it begins. For that reason, 70 percent of cases of ovarian cancer are diagnosed when the cancer has already reached an advanced stage.
In these later stages, the survival rate drops to only 20 percent to 30 percent. For that reason, scientists and doctors have long sought an effective early screening test.
The new study was led by Dr. Usha Menon, head of the Gynaecological Cancer Research Unit at University College London. The team randomly assigned almost 203,000 postmenopausal women to either no ovarian cancer screening or to screening with transvaginal ultrasound plus a blood test that finds a marker for ovarian cancer, called CA125. A third group was screened using transvaginal ultrasound alone.
Between 2001 and 2005, the researchers uncovered 87 ovarian cancers. The specificity of the tests was best in the combined screening group. In that cohort, fewer retests were needed and almost ninefold fewer surgeries were required, the researchers noted.
The team found that screening was able to identify most women with cervical cancer. The combination of the blood test and ultrasound found 90 percent of the cancers, while ultrasound alone found 75 percent of the cancers.
Almost 50 percent of all the cancers found were in an early stage (stage I or II), the researchers noted. And 48 percent of the more invasive ovarian cancers detected were designated as being stage I tumors. Usually, only 28 percent of ovarian cancers are identified in this early stage, the researchers pointed out.
To see whether these screening strategies have an impact on mortality, the women will continue to be screened through 2012 and followed until the end of 2014, the researchers said.
Menon stressed that it’s too early to make firm recommendations based on these early findings.
“Preliminary results are encouraging,” she said. “Both types of screening can be used on a large scale, and both successfully pick up ovarian cancers. But for a final answer as to whether ovarian cancer screening will save lives, we need to wait till 2015, when the trial will be finished.”
For his part, the ACS’ Smith said that experts have learned to be cautious when it comes to advocating a particular screening method for ovarian cancer.
“What we have is a long line of disappointing findings using either CA125 alone or ultrasound alone,” he explained. But he added that, “in combination, the performance appears to be much better.”
Although some women are getting these tests in the United States, women should not be asking to get these tests based on this preliminary data, Smith said. “Right now, the only group of women that is recommended to undergo any testing for ovarian cancer are women who are at very high risk due to family history,” he said.
“This screening trial is both a test of whether we can actually deliver these tests and whether we have shown better survival. But more importantly, have we shown that there is a lower rate of ovarian cancer deaths?” Smith said.
Wine Color Won’t Change Breast Cancer Risk
Despite red wine’s healthy reputation, study finds it won’t lower cancer odds
Although moderate consumption of red wine may offer some benefit for your heart, it won’t help decrease the risk of breast cancer in women, new research suggests.
“If you choose to drink at all, choose your drink based upon what tastes good to you, because wine is not associated with a decreased risk of breast cancer, regardless of the type,” said study author Polly Newcomb, program head of cancer prevention at the Fred Hutchinson Cancer Research Center in Seattle.
The findings were published in the March issue of Cancer Epidemiology, Biomarkers & Prevention.
This study comes on the heels of research released last week that found even one drink a day could increase a woman’s risk of developing cancer. That study, which was published in the online version of the Journal of the National Cancer Institute, reported that for every additional drink consumed per day, there are about 15 extra cases of cancer diagnosed for every 1,000 women under age 75, and that most of those cancers are breast cancer.
However, although alcohol has been found to be a factor that increases breast cancer risk, Whitcomb and her colleagues wondered if the type of alcohol might make a difference. Red wine has been touted as a heart-healthy drink, and the researchers set out to see if wine type made a difference in breast cancer risk.
The researchers enrolled 6,327 women between the ages of 20 and 69 who had been diagnosed with invasive breast cancer, and 7,558 women without cancer to serve as a control group. All of the women were from Wisconsin, Massachusetts (excluding Boston) and New Hampshire.
All of the women were surveyed by telephone about their breast cancer risk factors, including their drinking habits. Women with cancer were surveyed within a year of being diagnosed.
The researchers found that women who drink more than 14 drinks per week had a 24 percent increased risk of breast cancer. However, in this study, wine consumption was not associated with an increased risk of breast cancer, though it wasn’t associated with any benefit either.
“So many causes of cancer are unknown, but alcohol is a modifiable risk factor for breast cancer,” said Newcomb, who suggested that if women choose to drink alcohol at all, they should limit their consumption to no more than one drink per day.
Oncologist Dr. Virginia Kaklamani, from Northwestern Memorial Hospital in Chicago, agreed. “Drinking a small amount of alcohol is generally not harmful, but more than two drinks a day can become harmful,” she said.
And, women who have other risk factors for breast cancer, such as a family history or obesity, should talk with their doctor about how alcohol might affect their risk profile.
Folic Acid Supplements Raise Prostate Cancer Risk
But 10-year study also showed having enough folate in diet might offer protection
A 10-year study has found that men who took folic acid supplements faced more than twice the risk of prostate cancer as those who didn’t take the supplements.
But the incidence of prostate cancer in the study was slightly lower in men who simply got adequate amounts of folate in their diet, according to a report in the March 10 online issue of the Journal of the National Cancer Institute.
“What we think is that perhaps too much folate is not necessarily beneficial, whereas adequate levels may be,” said study leader Jan Figueiredo, an assistant professor of preventive medicine at the University of Southern California.
Folic acid is a synthetic version of folate, a basic nutrient found in green, leafy vegetables. In the study, which followed 643 men for slightly more than a decade, the estimated prostate cancer risk was 9.7 percent for the men who took the daily 1-milligram supplements, and 3.3 percent for men who took a placebo.
“Folate plays an important role in cell growth and division, and cancer cells often uprate their folate receptors,” Figueiredo noted. “Folic acid, the synthetic version, has more bioavailability, meaning that the effective dose in the cell is higher than what you get from natural sources.”
Dietary sources of folic acid in the United States now include cereals and other grain products. The U.S. Food and Drug Administration has required folic acid enrichment of those foods since 1996, in part to reduce the incidence of birth defects affecting development of the central nervous system.
“Since we fortified, the amount of folate we consume from fortified foods is probably more than sufficient,” Figueiredo said.
The newly reported results resemble those of a study done several years ago by Victoria Stevens, strategic director of laboratory services at the American Cancer Society, who specializes in research on folate metabolism.
That study of folate intake and prostate cancer “found that it really didn’t have much effect,” Stevens said. “Our study actually suggested that folate might be protective for men with advanced prostate cancer, a group that wasn’t included in this study.”
Overall, “it’s a pretty complicated picture,” Stevens said. “Previous epidemiological evidence suggests that not having enough folate can be bad, but having an excess might not be good. You need to have adequate folate nutrition. But it doesn’t get better if you have more, and it may get worse.”
The study is the latest to throw cold water on the hope that supplements can reduce the risk of cancer. Two studies reported late last year that supplements containing selenium, vitamin E and vitamin C had no effect on the incidence of prostate cancer.
One of those studies included more than 35,000 men aged 50 and over who were followed for more than five years, and the other included almost 15,000 male physicians aged 50 and over who were followed for an average of eight years.
“It is safe to conclude that cancer prevention is not going to be as simple as recommending high-dose micronutrient supplements for middle-aged and older adults,” said an editorial accompanying the latest report.
Detailed studies to understand how diet and supplements affect biological mechanisms of cancer in humans are needed, as well as large-scale epidemiological studies looking for ways in which diet can reduce risk, according to the editorial by Alan Kristal of the Fred Hutchinson Cancer Research Center in Seattle and Dr. Scott Lippman of the M.D. Anderson
Cancer Center in Houston.
“There is no evidence that supplements of any type reduce cancer risk, and increasing evidence that they may increase the risk for some cancers in some people,” said Kristal, who is a professor of epidemiology and associate director of the cancer prevention program at Fred Hutchinson. “The only exception is calcium for recurrence of colorectal polyps, where there is solid evidence that calcium can reduce risk.”
Study links blood types to pancreatic cancer risk
People with type O blood have a much lower risk for pancreatic cancer, while those with type B blood have the worst risk, researchers said in a study that may help explain what causes one of the deadliest kinds of cancer.
Compared to people with type O, those with blood type A have a 32 percent higher risk of pancreatic cancer, those with type AB have a 51 percent higher risk and those with type B have a 72 percent higher risk, the researchers found.
The findings, appearing in the Journal of the National Cancer Institute, were based on 107,503 men and women whose health has been tracked since the 1970s and 1980s.
The findings are not likely to have immediate value for doctors and patients dealing with the disease, but could play a role in the future in developing useful screening methods, said Dr. Brian Wolpin of the Dana-Farber Cancer Institute in Boston and Harvard Medical School, who led the study.
Finding this association between blood type and pancreatic cancer risk gives scientists new insight into the biological mechanisms involved in the disease, Wolpin said.
“There are very few known genetic risk factors for pancreatic cancer. And what this study shows is that blood type, which is defined by a gene on your ninth chromosome, appears to be associated with risk of developing this disease,” Wolpin said in a telephone interview.
“It may indicate that either this gene that defines your blood type, or a nearby gene on chromosome nine, is important and may actually be an inherited risk factor for pancreatic cancer,” Wolpin added.
The American Cancer Society says 34,290 Americans die of pancreatic cancer every year, making it the fourth leading cause of cancer death in the United States.
Pancreatic cancer often spreads quickly and in many people is not detected until it is in an advanced stage when surgical removal is not possible.
Clean living could cut third of many cancers
Healthier living could prevent about a third of the most common cancers in rich countries and about a quarter in poorer ones, international researchers said.
Better diets, more exercise and controlling weight could also prevent more than 40 percent of colon and breast cancer cases in some countries, according to the study which urged governments and individuals to do more to cut the number of global cancer deaths each year.
“At the time of publication, roughly 11 million people worldwide are diagnosed with cancer and nearly eight million people die from cancer each year,” said Michael Marmot, who led the study from the World Cancer Research Fund and the American Institute for Cancer Research.
“However, cancer is mostly preventable.”
The study involved 23 experts who analyzed both the incidence of 12 common cancers across the world and data on diet, exercise and weight to see how these factors contributed to kidney, mouth, lung, gallbladder and the other cancers.
The researchers found that healthier living would prevent 43 percent of colon cancer cases and 42 percent of breast cancer cases in Britain, and 45 percent of bowel cancer and 38 percent of breast cancer cases in the United States.
The findings follow the same groups’ study in 2007 that showed how quickly people grow and what they eat are both significant causes of cancer.
They recommended — in line with what health experts, including governments and the U.N. World Health Organization, have long been advising — that people follow diets based on fruits, vegetables and whole grains and go easy on red meats, dairy products and fats.
The team also looked at China and Brazil as representatives of low- and middle-income countries, respectively.
Overall improving diet, exercise and weight would in the United States prevent more than a third of the 12 most common cancers — which also included stomach, womb (uterus), prostate, pancreas and esophagus tumors.
This amounted to 39 percent of the cancers in Britain, 30 percent in Brazil and 27 percent in China.
“This report shows that by making relatively straightforward changes, we could significantly reduce the number of cancer cases around the world,” Marmot said in a statement.
“On a global level every year, there are millions of cancer cases that could have been prevented and this is why we need to act now before the situation gets even worse.”
Waiting Is the Hardest Part in Biopsies
Study finds stress hormone levels abnormal among women waiting for breast biopsy results.
What has been intuitively obvious to women for eons now has “real” scientific backing. Women who are waiting for results after a breast biopsy experience abnormalities in the levels of a stress hormone known as cortisol, a fact that might not only be damaging to overall health but might compromise future treatment if, in fact, the results come back positive.
The findings, appearing in the March issue of Radiology, argue for faster relaying of results to patients.
“For a long time, there has been the recognition that women should find out sooner what they have, but there was just not much effort put into it,” said Dr. Elvira V. Lang, an associate professor of radiology at Harvard Medical School in Boston and an author of the study. “When women just say they’re stressed, there’s a tendency to put it aside as psychological. But once you can show there can be adverse effects on the immune system and on what the next steps are, particularly in women who may be diagnosed and women who have future interactions with the health-care system, then this gets a completely different light on it.”
“The medical community isn’t going to believe this until there’s some biochemical data,” she added.
“These findings don’t surprise me,” said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. “It’s very stressful, and we try to have biopsies that have as quick a turnaround as possible. We have emergency medical records so patients today are going to get a CAT scan, are going to get off the table, walk off the elevator and see me and get their results immediately.”
More than a million breast biopsies are performed in the United States each year, with 80 percent of them turning up clear.
The researchers obtained cortisol samples from the saliva of 126 women, 18 to 86 years old, each day for five days after they had undergone a large-core breast biopsy.
They then compared cortisol levels among women who did not yet know the outcome of the biopsy (“uncertain group”), women who had a diagnosis of cancer (“known malignant group”) and women who were relieved to know they did not have cancer (“known benign group”).
Women learned their outcome between one and six days after the procedure. The mean cortisol “slope” for women in the uncertain group was flatter than that of women who had a benign result but similar to that for women who had learned they had cancer.
“Normally, cortisol levels are high in the morning and get lower during the day, so what really counts is the slope over the daytime,” Lang explained. “The cortisol mechanism is set up for responding to acute stress so we can adapt quickly, like fight or flight. That’s a good thing. But if the system gets overstressed, then you don’t react to quick things that happen in daily life in an appropriate fashion.”
“It’s not like this fine-tuned Swiss clock anymore,” she said. Everything from wound healing to blood sugar, blood pressure and immune defense can be affected if the mechanism that regulates the cortisol system is impaired.
“Particularly now, in these times of uncertainty, let’s acknowledge that uncertainty can wreck your immune system,” Lang said.