Melanoma is a doubtlessly lethal type of pores and skin most cancers that impacts individuals of each racial and ethnic group. Publicity to ultraviolet, or UV, rays from the solar is the danger issue most carefully linked to creating melanoma. In truth, sunburns have been related to doubling one’s danger of melanoma.
As a result of sunscreen can block UV rays and subsequently scale back the danger of sunburns, it in the end could scale back the danger of creating melanoma. Subsequently, the promotion of sunscreen as an efficient melanoma prevention technique is an affordable public well being message.
This can be true for light-skinned people, equivalent to individuals of European descent, however this isn’t the case for darker-skinned people, equivalent to individuals of African or Asian descent.
The general public well being messages promoted by many clinicians and public well being teams concerning sunscreen suggestions for dark-skinned individuals are not supported by the out there scientific proof. Media messaging worsens the issue with headline after headline warning that black individuals may also develop melanoma and that black individuals are not immune.
To make certain, they will get melanoma, however the danger may be very low. In the identical method, males can develop breast most cancers, nevertheless, we don’t promote mammography as a method to battle breast most cancers in males.
This message is vital to me as a black board-certified dermatologist and well being providers researcher at Dell Medical Faculty on the College of Texas at Austin, the place I’m the director of the pigmented lesion clinic. On this capability, I handle sufferers at excessive danger for melanoma.
Melanoma in black individuals shouldn’t be related to UV publicity
Within the U.S., melanoma is 30 occasions extra frequent amongst white individuals than black individuals.
In black individuals, melanoma normally develops in components of the physique that aren’t uncovered to the solar, such because the palms of the palms and soles of the toes. These cancers are known as “acral melanomas,” and sunscreen will do nothing to cut back the danger of those cancers.
When was the final time you had a sunburn on the palms or soles? Even amongst white individuals, there isn’t any relationship between solar publicity and the danger of acral melanomas. Famously, Bob Marley died from an acral melanoma on his large toe, however sunscreen wouldn’t have helped.
The uncommon type of pores and skin most cancers that killed Bob Marley is considered attributable to an harm or trauma.
Two years in the past my analysis group performed a scientific assessment wherein we analyzed the entire printed medical literature associated to UV publicity and melanoma in individuals of shade. This contains these of African, Asian, Pacific Islander, Indigenous, and Hispanic descent. Of the 13 research that met our standards for inclusion, 11 confirmed no affiliation between UV publicity and melanoma.
Among the many two research that confirmed an affiliation, one examine confirmed a constructive affiliation between melanoma and UV publicity in black males. However that very same examine additionally examined UV publicity and melanoma in different teams, together with black ladies, white women and men, and Hispanic women and men. In these different teams the researchers discovered no affiliation between UV publicity and melanoma. It is a stunning consequence, provided that white individuals are the group wherein the affiliation between UV publicity and melanoma has been constantly demonstrated. This calls into query the validity of the examine outcomes.
The opposite examine displaying an affiliation between UV and melanoma was amongst Hispanic males in Chile primarily based on latitude throughout the nation. A significant caveat to this examine is that the town with the best variety of melanomas can also be house to a big inhabitants of Chileans of Croatian descent, who wouldn’t be thought-about individuals of shade.
Sadly, none of those research measured melanin concentrations of people, so it isn’t attainable to know whether or not theoretically lighter-skinned individuals of shade could also be in danger for UV-associated melanoma. Nonetheless, even in light-skinned East Asian people, there isn’t any proof that UV publicity is linked to melanoma.
The underside line is that the hyperlink between UV publicity and melanoma in individuals of shade has been studied many occasions over and has yielded little to no proof of a connection.
Racial disparities in melanoma outcomes will not be associated to UV publicity
Many dermatologists typically level out that black sufferers have a tendency to indicate as much as the physician with later-stage melanoma, which is true. Nonetheless, this is a matter of entry and consciousness and has nothing to do with sunscreen software or safety from the solar. Black individuals ought to pay attention to growths on their pores and skin and search medical consideration if they’ve any altering, bleeding, or in any other case regarding spots, significantly on the palms and toes.
Nonetheless, the notion that common software of every day sunscreen will scale back an already extraordinarily uncommon incidence is nonsensical.
UV radiation does have an effect on darkish pores and skin and might trigger DNA damage; however, the damage is seven to eight times lower than the damage done to white skin, given the natural sun-protective effect of increased melanin in darker skin.
To be clear, using regular sunscreen may help with reducing other effects of the sun’s rays such as sunburns, wrinkling, photoaging, and freckling, which are all positive. But for the average black person, sunscreen is unlikely to reduce their low risk of melanoma any further.
If sunscreen were important in the prevention of melanoma in dark-skinned patients, then why have we never heard of an epidemic of melanoma in sub-Saharan Africa, a region with intense sun, a lot of black people, and little sunscreen?
In certain subpopulations of black people, such as those with disorders causing sun sensitivity, or patients with albinism – a condition in which people produce little or no melanin – or those with suppressed immune systems, sunscreen use may reduce the risk of melanoma. But if you don’t fall into one of these categories, any meaningful risk reduction from the application of sunscreen is unlikely.
One-size-fits-all public health messaging misses the mark
Many dermatology and skin cancer-focused organizations – including a few of which I belong to – promote the public health message of sunscreen use to reduce melanoma risk among black patients. However, this message is not supported by evidence. There exists no study that demonstrates sunscreen reduces skin cancer risk in black people. Period.
This issue of regular sunscreen use in black people was made even more pressing after the release of two recent studies on sunscreen absorption in the Journal of the American Medical Association. This study showed that significant amounts of certain chemical sunscreen ingredients can get in the blood when used under maximal conditions, with unknown impacts on human health.
To me, the most shocking part of the studies were that most of the participants were black, the group least likely to derive any meaningful associated health benefits from sunscreen, while being exposed to potentially harmful levels of chemicals.
As dermatologists and public health advocates, we can improve how we educate patients and the public about melanoma prevention without promoting public health messages that are grounded in fear and lack evidence. black people should be informed that they are at risk of developing melanoma, but that risk is low.
Any dark-skinned person who develops a new, changing or symptomatic mole should see a doctor, particularly if the mole is on the palms or soles. We don’t know what the risk factors are for melanoma in black or dark-skinned people, but they certainly are not UV rays.
Written by Adewole S. Adamson, Assistant Professor of Internal Medicine (Division of Dermatology), University of Texas at Austin.
This article was first published in The Conversation.