Skin cancer risk factors among Black South Africans-the Johannesburg Cancer Study, 1995-2016

Data from this study was part of the Master's dissertation of Ms Babongile C. Ndlovu, through the University of the Witwatersrand.DATA AVAILABILITY STATEMENT : The author(s) confirm that they had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. The dataset for this publication is not publicly available and can be obtained from the corresponding author on request.BACKGROUND : The Black population has lower skin cancer incidence compared to White, Indian/Asian, and Mixed-race populations in South Africa; however, skin cancer still exists in the Black population. The aim of this study is to identify risk factors associated with skin cancer among Black South Africans. MATERIALS AND METHODS : A case-control study was conducted. Cases were patients with keratinocyte cancers (KCs) and/or melanoma skin cancers (MSCs) and controls were cardiovascular patients. Sociodemographic exposures, environmental health variables, smoking, and HIV status were assessed. Stepwise logistic regression was used to identify risk factors associated with KCs and MSCs. RESULTS : The KCs histological subtypes showed that there were more squamous cell carcinomas (SCCs) (78/160 in females, and 72/160 in males) than basal cell carcinomas (BCCs). The SCC lesions were mostly found on the skin of the head and neck in males (51%, 38/72) and on the trunk in females (46%, 36/78). MSC was shown to affect the skin of the lower limbs in both males (68%, 27/40) and females (59%, 36/61). Using females as a reference group, when age, current place of residency, type of cooking fuel used, smoking, and HIV status were adjusted for, males had an odds ratio (OR) of 2.04 for developing KCs (confidence interval [CI]: 1.08–3.84, p = .028). Similarly, when age, current place of residency, and place of cooking (indoors or outdoors) were adjusted for, males had an OR of 2.26 for developing MSC (CI: 1.19–4.29, p = .012). CONCLUSIONS : Differences in the anatomical distribution of KCs by sex suggest different risk factors between sexes. There is a positive association between being male, smoking, rural dwelling, and a positive HIV status with KCs and being male and rural dwelling with MSC. The rural dwelling was a newly found association with skin cancer and warrants further investigation.The South African Field Epidemiology Training Program. The National Cancer Registry, South African Field Epidemiology Training Program, and the South African Medical Research Council supported the publication costs of the paper.https://onlinelibrary.wiley.com/journal/20504527hj2023Geography, Geoinformatics and Meteorolog