New insights into the aetiology of scrotal cancer, a nationwide case-control study in the Netherlands

Background Although scrotal cancer is traditionally regarded as an occupational disease, there is increasing evidence that factors which are involved in cutaneous and genital carcinogenesis might play a role in the carcinogenesis of scrotal cancer. Objective This exploratory study aimed to detect exposures that might have an aetiological relation with scrotal cancer. Methods A nationwide population-based case-control study was conducted in the Netherlands. The patients were identified through the Netherlands cancer registry. Controls were recruited among acquaintances of the cancer registry registrars. The participants completed a questionnaire that included questions on occupational exposures, naked sunbathing, use of sunbeds, skin diseases and their treatments, treatments for cancer and sexually transmitted diseases. Age-adjusted odds-ratios (ORs) were calculated. Results Forty-seven scrotal cancer patients and 125 controls completed the questionnaire. The patients were categorized according to histology of the scrotal tumours. Having had a skin disease (OR=6.3, 95% CI=1.8-22), especially psoriasis (OR=8.7), increased the risk of squamous cell carcinomas (SCC) of the scrotum. A previous cancer diagnosis may affect the risk of scrotal basal cell carcinomas (BCC; OR=4.9, 95% CI=0.9-27.3). Furthermore, an association between the number of sexual partners and the occurrence of scrotal sarcoma was found. Conclusion Scrotal SCCs may be related with skin diseases or skin disease treatments. Having had cancer may be a risk factor for a BCC of the scrotum. Scrotal sarcomas seem to be correlated with the number of sexual partners. This study suggests that scrotal cancer has characteristics of both cutaneous and genital carcinogenesis.