Young white men with melanoma have a 55 percent higher risk of death from the disease than their female counterparts, suggesting biological sex differences may play a role in outcomes in this deadly cancer, a new Stanford study shows. Though other studies have found that older men tend to fare worse when it comes to melanoma - the most serious form of skin cancer - this is one of the first to compare survival between men and women in a younger population.
The study focused on adolescent and young adults between the ages of 15 and 39 years, who were diagnosed between 1989 and 2009. Among the more than 26,000 patients studied, 1,561 died of the disease. Though males accounted for fewer cases overall (40 percent), they accounted for 64 percent of the deaths. Susan Swetter, MD, a professor of dermatology and the study's senior author, said:
Studies worldwide have demonstrated that women diagnosed with melanoma tend to fare better than men in terms of improved survival, and this has mostly been attributed to better screening practices and behaviors in women that result in thinner, more curable tumors, and/or more frequent physician visits in older individuals that result in earlier detection. Our study focused on survival differences between young men and women diagnosed with cutaneous (skin) melanoma, who constitute a generally healthy population compared to the older adults who have primarily been studied.
The researchers found that the young men were significantly more likely to die of melanoma than young women their age, even taking into account factors typically related to poor prognosis, such as the tumor's thickness, its location, histologic subtype and whether or not it had spread to other parts of the body.
"Our results present further evidence that a biologic mechanism may contribute to the sex disparity in melanoma survival, particularly since adolescent and young adults see physicians less frequently and are less likely to have sex-related behavior differences in skin cancer screening practices than older individuals," said Swetter, who directs the Stanford Pigmented Lesion and Melanoma Program.
The results follow a previous analysis in Europe in 2012 which found that women with melanoma have a 30 percent survival advantage compared to men, despite similar follow-up and treatment, she said. And a more recent study out of Europe showed that even women with advanced melanoma do better in terms of survival.
Christina Gamba, MD, who recently graduated from Stanford's medical school, was the study's first author. She told me, "We feel that our study in a largely healthy, young population adds further evidence that a biological mechanism may be at play. Several theories for the survival disparity include differences in sex hormones, vitamin D metabolism, and immune regulation, but further investigation is needed to explore these proposed mechanisms."
The research appears online today in JAMA Dermatology.
Previously: New research shows aspirin may cut melanoma risk, New skin cancer target identified by Stanford researchers, How ultraviolet radiation changes the protective functions of human skin and Working to prevent melanoma
