A study published last month offers some new hope for helping prevent ovarian cancer - in the form of a baby aspirin - and may add to the growing body of evidence that inflammation plays a role in the disease. But researchers caution that more study is needed.
Ovarian cancer, the fifth most common cause of cancer-related death among women in this country, “is a high-fatality cancer, primarily because it’s usually diagnosed at a later stage,” says Marian Neuhouser of the Fred Hutchinson Cancer Research Center in Seattle. There’s no diagnostic test for it and symptoms are maddeningly nonspecific, which makes preventing it from developing even more vital.
The study, led by researchers at Harvard T.H. Chan School of Public Health and published in the journal JAMA Oncology, found that women who had been recently taking low-dose (or baby) aspirin at least twice per week were 23 percent less likely to develop ovarian cancer than nonusers or past users. The results were based on data from more than 200,000 women followed for more than 25 years as part of the Nurses’ Health Study at Brigham and Women’s Hospital in Boston. An earlier study had found that almost daily aspirin use could reduce ovarian cancer risk by 10 percent.
Interestingly, in the Harvard study, use of standard-dose aspirin didn’t appear to affect ovarian cancer risk. Use of acetaminophen also didn’t seem to have an effect. However, long-term use of non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, were associated with increased risk.
The differing results and possibility of statistical anomalies raise questions that will need to be explored in future research. But because aspirin is known to lower inflammation, authors of the study believe their results bolster the theory that inflammation is a culprit in ovarian cancer. Inflammation occurs with ovulation, and it can also be chronic, because of environmental pollutants, harmful lifestyle behaviors such as smoking, and some health conditions.
Does this mean that women who don’t already take low-dose aspirin should start? Not necessarily, said Mollie Barnard, who led the study as a doctoral fellow in epidemiology at Harvard. “If future studies confirm our findings, conversations between doctors and patients on the risks and benefits of low-dose aspirin use may broaden to include ovarian cancer prevention.”
Although there are other factors, such as diet, that can influence inflammation and, potentially, cancer, links between diet and ovarian cancer risk are less clear than they are for other forms of the disease. That’s partly because there’s less research to draw from, Neuhouser said; ovarian cancer is relatively rare compared with other cancers, so studies would have to enroll a very large number of women to spot any patterns or associations.
One existing study, a 2007 randomized controlled trial from the Women’s Health Initiative, assigned women to eat their usual diet or a low-fat diet rich in vegetables, fruits and whole grains. It found that the women in the low-fat diet group were 17 percent less likely to develop ovarian cancer during an average of eight years of follow-up. “That’s stronger than for most of the other cancers,” Neuhouser said.
A 2014 Women’s Health Initiative study, which Neuhouser co-led, looked at diet quality and survival after a diagnosis of ovarian cancer. Of the 636 postmenopausal women studied, those with the best diet quality before diagnosis, meaning those who hewed most closely to the Dietary Guidelines for Americans, were 27 percent less likely to die of ovarian cancer or any other cause during 17 years of follow-up.
“Often ovarian cancer feels like a dire diagnosis because if you look at the statistics, the five-year survival rate is very low,” Neuhouser said. “Some of these data that are coming out do offer a glimmer of hope that there are things people can do to improve their odds of survival.” Controlling weight would be one example; Neuhouser points out that the link between higher body weight and ovarian cancer is stronger than it is for most other cancers.
As for diet, she recommends the Mediterranean diet as one option. Like other anti-inflammatory diets, it is rich in vegetables, fruits, whole grains, beans and legumes, nuts and seeds, and healthy fats from foods like fish, avocados and olive oil, while limiting saturated fat, sugar and refined carbohydrates, and avoiding excess alcohol and caffeine. The value of an anti-inflammatory diet extends far beyond possible cancer prevention and better survival odds, because chronic inflammation contributes to heart disease and other health conditions.
Unfortunately, the ideal time to think about eating for cancer prevention is long before most people are concerned about developing it. “It does take decades for people to develop cancer,” Neuhouser said. “The most common years to develop cancer are when they’re in their 50s, 60s or 70s. Most people are not thinking about what they can do now to prevent risk of cancer later, other than maybe smoking avoidance or smoking cessation.”
But prevention - and survival - strategies take on more importance when detection is difficult. Symptoms of ovarian cancer - bloating, pelvic or abdominal pain, difficulty eating or feeling full quickly, and frequent or urgent urination - are similar to symptoms caused by other health problems. But the American Cancer Society says that when these symptoms are caused by ovarian cancer, they tend to occur more often or are more severe than normal. If you have these symptoms more than 12 times a month, talk to your doctor.