KYOTO, JAPAN — Does regular use of aspirin or other NSAIDs protect against melanoma?
The question remains wide open following the presentation of two large, well-controlled studies that drew diametrically opposite conclusions at an international investigative dermatology meeting.
“The study designs are very different, and each has its strengths and weaknesses. You can't say one is better than the other,” session cochair Dr. Suephy Chen, director of the dermatology clinical outcomes and research unit at Emory University, Atlanta, said in an interview.
Dr. Clara Curiel-Lewandrowski presented a case-control study involving 400 cutaneous melanoma patients and 600 controls matched for gender, age, and neighborhood.
The primary study hypothesis, based upon preliminary data, was that statin therapy would reduce the risk of developing melanoma by upward of 30%. That didn't happen. In fact, there was no indication that long-term use of statins reduced melanoma risk, according to Dr. Curiel-Lewandrowski of Harvard Medical School, Boston.
But the study was also designed to look at NSAID use. The prevalence of a history of more than 5 years' duration of NSAID use, regardless of frequency, was 18% in melanoma patients, compared with 24.2% in controls.
After adjustment for baseline melanoma risk factors, this translated into a 27% relative risk reduction in conjunction with more than 5 years of NSAID use.
The risk reduction seen with long-term NSAIDs was driven mainly by aspirin use. More than 5 years of aspirin use was reported by 13.3% of the melanoma group and 21.2% of controls. This worked out to an adjusted 44% relative risk reduction.
In a separate presentation, Dr. Maryam M. Asgari presented a prospective cohort study involving 63,809 participants in the National Institutes of Health-sponsored Vitamins and Lifestyle (VITAL) study.
On a detailed questionnaire administered at study entry, participants self-reported their NSAID consumption during the prior 10 years. They also listed their melanoma risk factors, including family history of melanoma, a personal history of three or more severe sunburns during ages 10–20 years, having had moles removed, and red or blond hair color.
During an average follow-up of 5 years, 349 new cases of melanoma occurred. After adjusting for melanoma risk factors as well as indications for NSAID use, investigators found no association between melanoma risk and overall use of NSAIDs, duration of use, or dosage. NSAID use did not influence tumor invasion, Breslow Depth, or risk of metastasis, said Dr. Asgari, a dermatologist and Moh's surgeon in the division of research at Kaiser Permanente, Oakland, Calif.
The study was funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases and the National Cancer Institute.
Investigators found no association between melanoma risk and overall use of NSAIDs. DR. ASGARI