Dr Derrick Phillips
Senior Dermatology Registrar, Mersey Deanery and British Skin Foundation Spokesperson
Dr Derrick Phillips will be taking up a Consultant post at Imperial College Healthcare NHS trust in August
Summer time is a carefree period punctuated by trips to the beach, foreign holidays and lazy afternoons in the park. For those with white skin, sun-seeking behaviour is counterbalanced against the ever-present risk of sunburn in the short term, and in the long run, skin cancer.
To reduce the risks of sunburn and skin cancer, dermatologists and healthcare professionals have consistently advised members of the public to take appropriate precautions during sun exposure, these include; use of a high factor sunscreen (SPF 30+ with 5 UVA stars), wearing appropriate clothing (e.g. hat, sunglasses and t-shirt) and staying in the shade between 11am and 3pm. But does this advice hold true for all ethnicities and skin types? Should individuals with skin of colour use sunscreen to protect against skin cancer?
The causal link between exposure to ultraviolet (UV) radiation from the sun and skin cancer in white populations has been consistently demonstrated by clinical research, however such studies have often excluded individuals with skin of colour. There has been a tendency for the results from these studies to be generalised and the recommendations applied to all individuals regardless of ethnicity, skin colour and tanning ability. Whilst it is true that skin cancer can affect individuals with skin of colour, it is a much rarer occurrence and does not seem to be associated with UV exposure.
New research into UV exposure
A recent systematic review conducted by Dr Adewole Adamson’s team at Dell Medical school (University of Texas at Austin), compiled data from 13 international studies to determine whether UV exposure was a risk factor for melanoma in individuals with skin of colour. Of the 439,009 melanomas reported across the included studies, 1.76% occurred in individuals with skin of colour. The data from this review suggested that UV exposure was not an important risk factor for the development of melanoma in individuals with skin of colour. This evidence supports what is seen in practice by dermatologists treating skin cancer. In addition, the predominant type of melanoma occurring in individuals with skin of colour is acral lentiginous melanoma, a tumour that affects non-sun exposed sites (e.g. palms, soles and nail beds) and is not related to sun exposure.
The data from this review suggested that UV exposure was not an important risk factor for the development of melanoma in individuals with skin of colour.
If UV exposure is not an important risk factor for the development of skin cancer in skin of colour, should we continue to promote the precautionary use of sunscreen in these individuals? It is clear that we need to move away from one size fits all medicine and provide more nuanced advice tailored to the individual. Sunscreen may be a less important intervention for individuals with skin of colour than increasing awareness of the signs of acral lentiginous melanoma, a disease that is often detected at a later, more advanced stage. Nevertheless, there are other benefits of using sunscreen and taking the precautions described. Pigmentary disorders such as melasma and post-inflammatory hyperpigmentation are common afflictions of individuals with skin of colour and can be exacerbated by sun exposure. The use of sunscreens with broadband UVA/UVB cover can protect against this, as well as preventing photoaging.
