Minority Melanoma Paradox is Invasive, Reversible

A retrospective review in Clinical, Cosmetic & Investigational Dermatology tried to answer the difficult question of why African Americans (AA), who have a much lower incidence of melanoma than Caucasians do, have a five-year survival rate that is drastically lower than it is for Caucasian patients. This is what's known as the "minority melanoma paradox," and the reasons for it are not well-understood.

A retrospective review in Clinical, Cosmetic & Investigational Dermatology tried to answer the difficult question of why African Americans (AA), who have a much lower incidence of melanoma than Caucasians do, have a five-year survival rate that is drastically lower than it is for Caucasian patients. This is what’s known as the “minority melanoma paradox,” and the reasons for it are not well-understood.

Melanoma is the deadliest type of skin cancer. Caucasians have a 27-fold higher incidence of melanoma than AA, but AA have more advanced melanomas at diagnosis. They also have a five-year survival rate which is 17.8% lower than the rate for Caucasians. Because the incidence of melanoma is so much higher in Caucasians, much of the medical literature, current research, and public health efforts have focused on this population. Even the most common melanoma measuring tool, the Fitzpatrick Skin Type Classification scale, was developed based on Caucasian patient data. Yet, studies report that when AA do develop melanoma, they tend to have more advanced tumors and poorer survival rates than Caucasians.

One trend noted in the review is that the incidence of invasive cutaneous melanoma for all races and sexes has decreased between 2010 and 2011 (24.02 vs 23.21 per 100,000). But when the age-adjusted incidence is stratified by race, AA experienced a much smaller decline in incidence (1.04—1.03 per 100,000) as compared to Caucasians (29.18–27.79 per 100,000).1 Additionally, AA females showed an increase in age-adjusted incidence of cutaneous melanoma from 0.97 to 1.08 per 100,000 between 2010 and 2011. Worse still, the give-year relative survival from cutane­ous melanoma among Caucasians between 2004 and 2010 was 92.9% for both sexes, whereas for AA (both sexes) it was 75.1%.

“Thus, despite lower incidence rates and protective aspects of darker pigmentation, studies ranging from 1982 to 2013 consistently report that AA have higher rates of more advanced melanomas and lower overall survivals,” the study authors noted.

One potential reason for this disparity is that routine self- and physician-skin examinations can improve the chances of early detection. But multiple studies have shown that minorities reported having significantly less physician performed full-body skin examinations. This problem has potentially been exacerbated by a strange policy lapse: the US Preventive Services Task Force still does not recommend screening full-body skin examination (self or professional) because it concluded that the evidence for its benefits are inconclusive.

“This lapse in public health education policy has allowed gaps in melanoma awareness, diagnosis, and treatment,” the team wrote.

The authors also noted important differences in socioeconomic status among AA that may contribute to the paradox. They point out that socioeconomic status can not only affect the ability to pay for and access care, but that it often affects the quality of that care as well. Thus, access and quality of medical care differs among minorities and may contribute to the melanoma disparity. The study also discussed important gaps in public education efforts and historical factors, such as experiments conducted on black slaves before and during the Civil War era, and a high general level of skepticism of the healthcare system among AA populations.

Furthermore, there is the possibility that the AA population is more susceptible to more aggressive types of melanoma — including acral and mucosal melanomas. Even when diagnosis and treatment were the same, some studies showed that AA and Caucasians outcomes differed. The survival rate for AA patients was shorter even when the patients were matched for stage of melanoma and similar medical treatment. This suggests that “the tumor growth in minorities is somehow intrinsically more virulent and aggressive,” the authors hypothesized.

The team calls for increases in public awareness for the AA population not just through media-guided education, but also through physician efforts.

“Fortunately, greater awareness of this issue can prompt both individual and societal change,” they concluded.