By Genevra Pittman
NEW YORK (Reuters Health) - Older women who regularly took aspirin - but not similar anti-inflammatory drugs - had a lower-than-average risk of developing the most dangerous form of skin cancer in a new study.
The findings are based on 12 years of data from the large, long-term Women's Health Initiative study and account for how much time study participants spent in the sun and whether they typically used sunscreen. But they do not mean all women should start taking aspirin to ward off skin cancer, according to the report's lead author.
"This study... correlates use of aspirin with lower melanoma risk, but it doesn't prove it," Dr. Jean Tang, from the Stanford University School of Medicine in California, told Reuters Health.
Melanoma cases have been on the rise in recent decades. The American Cancer Society estimates that about 77,000 new melanomas will be diagnosed in 2013 and just over 9,000 people will die of the disease.
For their study, Tang and her colleagues tracked almost 60,000 white women, ages 50 to 79, who reported their medication use and any new diagnoses on annual questionnaires.
During the research period, 548 women - less than one percent - were diagnosed with melanoma. Women who said they were regularly taking aspirin - meaning at least twice a week - at the start of the study were 21 percent less likely to develop melanoma than those not on anti-inflammatory medicines.
Use of aspirin for five years or longer was tied to a 30-percent reduction in skin cancer risk, according to the findings published in the journal Cancer.
However, women who took other non-steroidal anti-inflammatories - such as ibuprofen (marketed as Advil and Motrin) and naproxen (Naprosyn) - weren't any less likely to develop melanoma. Neither were users of acetaminophen, marketed as Tylenol.
NSAIDs including aspirin inhibit certain proteins that are known to play a role in tumor growth. So it's not clear why aspirin might lower the risk of melanoma, but other anti-inflammatory drugs wouldn't.
"There really isn't that great of a difference in the way these drugs work," said Dr. Randall Harris, a cancer researcher from The Ohio State University Medical Center in Columbus.
According to Tang, it's possible there just weren't enough women taking non-aspirin NSAIDs in her team's study to see a clear effect of those drugs.
Harris said the evidence has been piling up that aspirin and other NSAIDs are tied to a lower risk of a range of cancers, including breast, colon and lung cancer.
"In my opinion, it's certainly worth considering taking one of these compounds on a regular basis at a relatively low dose... two or three times per week, especially if you are at risk for developing any one of these malignancies," Harris, who wasn't involved in the new study, told Reuters Health.
He said people considering starting NSAIDs should talk with their doctor first to make sure they aren't using multiple drugs with the same impact. And patients should stop the drug immediately and also see their doctor if they notice any side effects.
Tang, however, doesn't think the evidence currently supports most people using aspirin and other NSAIDs to ward off cancer, including melanoma.
"For women who are at high risk (such as) somebody who's already had skin cancer, talk to your doctor about taking aspirin, because aspirin is still a drug," she said.
"The benefit needs to be weighed against some of the possible side effects."
SOURCE: http://bit.ly/10vczm1 Cancer, online March 11, 2013.