Speaking at a MIMS Learning webinar last week, Dr Sharon Belmo, consultant dermatologist at Croydon University Hospital and clinical lead at the Centre of Evidence Based Dermatology Skin of Colour Resource, said that misconceptions about skin cancer may contribute to its poorer prognosis in people of colour.
The incidence of skin cancer in skin of colour is much lower than in white skin, but it has a higher morbidity and mortality in black and Asian people.
UK data are not available, but figures from the USA suggest that the incidence of skin cancer is around 2% in black people, compared with 40% in white people.
Poorer prognosis
Malignant melanoma is the cause of 75% of skin cancer deaths, despite only accounting for 1% of all skin cancer cases. While melanoma primarily affects white people, it has been reported that people of colour are 1.5 times more likely to die from the disease.
'In black people, skin cancers are more aggressive and the prognosis is poorer … black people are more likely to die from skin cancer in comparison to white people,’ said Dr Belmo.
This disproportionately higher mortality is likely the result of several factors, Dr Belmo explained.
'The diagnosis might be delayed, and this might be because there is unfamiliarity with presentations of skin cancer in skin of colour. That means that when patients present, their skin cancer may already be at a very advanced stage. There are misconceptions amongst both patients and clinicians about whether people of colour even get skin cancer. And then, of course, there is a lack of diversity in public health skin cancer campaigns.’
Sun exposure in darker skin
In lighter skin, skin cancer generally occurs on sun-exposed sites, such as the face, chest and hands. In darker skin, melanoma and squamous cell carcinoma (SCC) occur on non-sun-exposed sites and this is something people need to be aware of, added Dr Belmo.
Referring to a 2021 study published in JAMA Dermatology, Dr Arif Aslam, consultant dermatologist and Mohs surgeon, wrote in a MIMS Learning module on skin cancer: 'While current evidence supports UV radiation as an important risk factor for melanoma in white populations, the evidence for this association in skin of colour is less clear’.
Dr Belmo added: 'We have to be careful when we give blanket statements about sunscreen use to prevent skin cancer in all skin types when, in actual fact, in the case of melanoma and SCC, there’s no evidence that UV light causes it [in skin of colour].’
Pigmentation
In a further example of differences in the presentation of skin cancer, Dr Aslam highlighted that pigmentation is present in more than 50% of basal cell carcinomas (BCCs) in skin of colour, compared with only 5-6% of BCCs in white skin. As a result, BCCs in skin of colour are often misdiagnosed as seborrhoeic keratosis.
Dr Belmo said: 'The incidence is lower [in skin of colour], but skin cancer shouldn’t be missed and I think this high mortality rate in black people is very worrying.'
The on-demand webinar ‘Dermatology for skin of colour’ is available to watch free on MIMS Learning. A free download of the 'Skin of colour matters’ print edition of MIMS Learning Dermatology is also available within the on-demand webinar module.
This webinar is part of a series of 16 learning modules, free for a limited time, aiming to help to fill the education gap around diversity in dermatology.
