Ethnicity and the epidemiology of skin cancer incidence: a retrospective population-based study in England, 2013-20

Introduction: Skin cancers primarily affect people of White ethnicity and lighter skin tones, but people of other ethnicities may face diagnostic delays and experience higher mortality, reflecting existing inequities in healthcare. This is the first study showing incidence data from the National Disease Registration Service (NDRS) cancer registry in England for skin cancers stratified by the seven broad ethnic groups. Methods: We used data from NDRS from 2013-20 to analyse melanoma, acral lentiginous melanoma (ALM), basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), cutaneous T-cell lymphoma (CTCL), and Kaposi sarcoma (KS). Tumour records were linked to datasets including census population data, Office for National Statistics (ONS) mortality data, Index of Multiple Deprivation and Hospital Episode Statistics. Ethnicity data were grouped into seven standardised broad ONS categories: White, Asian, Chinese, Black, Mixed, Other and Unknown. European age-standardized rates (EASR) were calculated using the 2013 European Standard Population and reported per 100,000 person years (PY). Results: Ethnic diversity in England increased between the 2011 and 2021 censuses. 'Unknown' ethnicity cases with registry data ranged from 19.2% for BCC to 5.0% for ALM. EASR of melanoma was 33 times higher in White (27.29 CI [27.12- 27.46]) than in Asian (0.82 CI [0.67- 0.99]) and 16 times higher in White than in the Black ethnic group (1.67 CI [1.37- 2.01)]. Similarly, cSCC was 14 more common in White compared (61.75 CI [61.49- 62.0]) with Asian (4.55 CI [4.15- 4.97]) and 13 times more common with the Black ethnic group (4.73 CI [4.17- 5.34], respectively. BCC was 26 times more common in White (153.69 CI [153.28-154.09] than in Asian (5.59 CI [5.16- 6.04]) and 27 times more common in White than in Black ethnic groups (5.98 CI [5.35- 6.65], respectively. However, EASR for ALM was highest in the Black ethnic groups. ALMs were less likely to be referred along the urgent suspected cancer pathways and more likely to present at a later stage than for melanoma overall. EASR for KS was significantly higher in Other and Black ethnic groups. Conclusion: A lack of high-quality published ethnicity data hampers our understanding of health disparities. These findings emphasize the need for better ethnicity data collection and regular audits to better understand and address needs of underserved populations.