PracticalDermatology

UV protection strategies—including UV avoidance and sunscreen use—are foundational to dermatologists’ and public health professionals’ strategy to reduce the incidence of skin cancers, particularly melanoma. However, a new analysis¹ focuses attention on the finding that UV exposure does not significantly correlate with risk for melanoma in patients of color and raises questions about the benefit of sunscreen recommendations for these individuals. For a population impacted by disparities in melanoma detection and outcomes, the current findings suggest an urgent need for further research to understand melanoma causes and risk in patients across all skin types.

Overview: Melanoma in Skin of Color

Individuals with dark skin types have a decreased incidence of melanoma and other skin cancers relative to Caucasian individuals, and this reduced incidence has been attributed to the protection afforded by melanin in the skin. For example, whites have a 27-fold higher incidence of melanoma than African Americans. However, rates of melanoma survival are lower in patients of color. Despite the lower relative incidence of melanoma, the five-year survival for African Americans is 17.8 percent lower than in whites.² African Americans tend to have more advanced melanomas at the time of diagnosis, compared to whites. In one study of patients who received surgical treatment for a first primary melanoma, 10-year melanoma-specific survival was lower in blacks (73 percent) than in whites (88 percent) and other races (85 percent).³

Delayed diagnosis has been implicated as a contributor to worse outcomes for melanoma in patients with skin of color. One study found that African American race was a predictor of melanoma stage greater than II, tumor diagnosed at autopsy, ulceration, and distribution in the extremities. In this analysis, the mean time for African American patients to receive treatment for melanoma was nearly twice as long as for whites—20.37 days compared with 11.25 days. Time to surgery for African American patients was 38.86 days, compared to 31.12 days for Caucasians.⁴

An Incomplete Picture?

Worse prognosis for patients with skin of color with melanoma has been ascribed to reduced access to care and false perception of reduced risk, among other factors. Increasingly, it seems that the pathogenesis of melanoma in skin of color warrants further research. Recently, researchers identified that, relative to Caucasians, melanoma has unique demographic, clinical, and genetic features in African Americans, Hispanics, and Asians that include gender and subtype predominance.⁵

The new analysis of 13 published research articles has drawn focus to the finding that UV exposure—until now considered a primary risk factor for melanoma in general—may not be strongly associated with melanoma risk in dark skin types.¹ For the analysis, skin of color included all races/ethnicities except for non-Hispanic white, Fitzpatrick skin types IV to VI, or tanning ability described as “rarely or never burns.”

The authors of the current analysis acknowledge that objective assessment of an individual’s UV exposure over time is difficult to quantify. They included articles that attempted to quantify UV exposure based on occupational exposure, childhood exposure, sunburn history, vacations to tropical destinations, measures of latitude, phototherapy sessions, tanning bed sessions, UV flux, UV index, irradiance, and/or estimated time spent outdoors.

Eleven of the 13 analyzed studies showed no association between UV exposure and melanoma in skin of color; two studies showed a statistically significant, positive association between UV exposure and cutaneous melanoma but only in Black and Hispanic males, respectively. One study found a positive correlation between melanoma incidence and UV index in Black men only and found a negative correlation between melanoma incidence and latitude.

The authors of the current analysis note that most of the included studies did not differentiate histologic subtypes of melanomas diagnosed. The incidence of acral lentiginous melanoma (ALM) is similar across racial and ethnic groups. However, owing to the overall lower incidence of melanoma in skin of color, ALM is the predominant subtype in this population and accounts for a disproportionate number of melanomas. The fact that ALM is not considered to be associated with UV further supports the notion that cumulative UV exposure is not a strong predictor of skin cancer risk in patients with skin of color.

If anything is controversial in the current analysis, it is likely the authors’ conclusion that “current guidelines suggesting photoprotection for melanoma prevention in skin of color are not supported by the current literature.”¹

Implications

While it is true that melanin is protective against UV damage to the skin, dermatologists and public health officials have been challenged for years to counter a false sense of security among certain patients of color who believe that darkly pigmented skin is protected from skin cancer. We know that UV exposure is a risk factor for skin cancers, including melanoma, as well as for skin aging. Therefore, all patients should continue to be counseled to practice UV avoidance and sunscreen use. It is worth noting that advancement in sunscreen formulation has led to more effective options for patients, including physical sunscreens that are cosmetically acceptable for use on dark skin. Additionally, daily use of sunscreens (with the potential addition of iron-oxide containing formulations to screen blue light) helps to protect from pigmentary changes, such as melasma. To say that suggesting photoprotection is not supported by the literature does not justify elimination of such suggestions.

Rather than refashion the UV avoidance message, a more appropriate approach based on the current literature involves two key strategies. One is to increase study on the causes of and risks for melanoma in individuals with skin of color. Only with a better understanding of the disease can we be best prepared to counsel, diagnose, and treat all of our patients.

Second, given the known disparities in diagnosis and care for melanoma in patients of color, it is essential that we expand initiatives to educate patients with skin of color about the need for skin self-exams, the proper conduct of skin self-exams, and the importance of seeking dermatologic assessment of any suspicious lesions. Importantly, patients with skin of color must be urged to carefully check the palms, soles, and nails for new or changing lesions. Patients also require specific education on the early appearance of ALM. While it is true that the ABCDE rule applies to these lesions, most early lesions—those that are best candidates for treatment—do not look like the new or changing “moles” that most patients are taught to look for.

1. Lopes FCPS, Sleiman MG, Sebastian K, Bogucka R, Jacobs EA, Adamson AS. UV Exposure and the Risk of Cutaneous Melanoma in Skin of Color: A Systematic Review. JAMA Dermatol. 2021 Feb 1;157(2):213-219.

2. Goldenberg A, Vujic I, Sanlorenzo M, Ortiz-Urda S. Melanoma risk perception and prevention behavior among African-Americans: the minority melanoma paradox. Clin Cosmet Investig Dermatol. 2015 Aug 5;8:423-9.

3. Collins KK, Fields RC, Baptiste D, Liu Y, Moley J, Jeffe DB. Racial differences in survival after surgical treatment for melanoma. Ann Surg Oncol. 2011 Oct;18(10):2925-36.

4. Boczar D, Restrepo DJ, Sisti A, Huayllani MT, Saleem HY, Lu X, Cinotto G, Manrique OJ, Spaulding AC, Forte AJ. Analysis of Melanoma in African American Patients in the United States. Anticancer Res. 2019 Nov;39(11):6333-6337.

5. Higgins S, Nazemi A, Feinstein S, Chow M, Wysong A. Clinical Presentations of Melanoma in African Americans, Hispanics, and Asians. Dermatol Surg. 2019 Jun;45(6):791-801.