Men taking ASA once a day are almost two times more likely to have a melanoma diagnosis, compared to men not exposed to the medication, according to a study published online in the Journal of the American Academy of Dermatology (Mar. 27, 2018).
Researchers found that women, however, do not have the same increased risk associated with ASA therapy. Men may be more vulnerable because compared to females, males (human and animal species) express lower levels of protective enzymes such as superoxide dismutase and catalase.
“These lower levels of protective enzymes suggest that a higher level of resulting oxidative cellular damage in men might contribute to the possibility of developing melanoma,” said senior study author Dr. Beatrice Nardone, professor of dermatology at the Northwestern University Feinberg School of Medicine in Chicago, in a press release.
Researchers were surprised with results because ASA has been reported to reduce risk of other diseases such as gastric, colon, prostate, and breast cancer. Copyright-free photo by pixabay.com.
That being said, the researchers emphasized that men should not stop taking ASA, as it is known to lower their risk of heart attack. Dr. Nardone and her colleagues suggested that increasing patient education about sun exposure, avoiding tanning beds, and getting regular skin checks by a dermatologist, particularly for individuals who are already at an increased risk for skin cancers, can result in early diagnosis and help educate men about the link between ASA and melanoma.
“Given the widespread use of [ASA] and the potential clinical impact of the link to melanoma, patients and health care providers need to be aware of the possibility of increased risk for men,” said Dr. Nardone.
Medical records of almost 200,000 patients who were ASA-exposed or ASA-unexposed (control group) were collected and analyzed for the study. Subjects were between 18 and 89 years of age, with no prior history of melanoma.
For the ASA-exposed patient population, the study included only patients who had at least one year of once-daily ASA exposure at a dose of 81 or 325 mg, occurring between 2005 and 2006. This allowed for at least five years of follow-up data to detect if melanoma occurred over time.
Out of a total of 195,140 patients, 1,187 were ASA-exposed. Of those ASA-exposed patients, 26 (2.19%, both men and women) had a subsequent diagnosis for melanoma. Out of the patients not exposed to ASA, 1,676 (0.86%, men and women) were diagnosed with melanoma.
When the groups were separated into men and women, men exposed to ASA had almost twice the risk for diagnosis of melanoma (adjusted relative risk: 1.83) compared to men in the same population who were not exposed to ASA.