Skin cancer prevalence among outdoor activity participants from Queensland, Australia: aquatic versus land-based sun exposure

Background To determine the prevalence of keratinocyte cancer and melanoma among people conducting aquatic and non-aquatic outdoor activities, and their associated ultraviolet radiation (UVR) exposures. Methods This was a cross-sectional study incorporating a survey and total body skin cancer screen. There were 1,403 participants attending a specialized skin cancer-focused general practice during the period of September 2021 to August 2024. The main outcomes measured were the point prevalence of pre-cancerous skin lesions, keratinocyte cancers (KC) ( i.e. , basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)) and primary cutaneous melanoma (MM). Results Of 1,403 participants (739 women, 664 men), 512 were identified as aquatic and 891 were identified as non-aquatic. Among aquatic participants, 98 of 512 (19.1%) participants were diagnosed with BCC, compared with 142 of 891 (15.9%) non-aquatic participants. Regarding SCC in the population, 46 of 512 (9.0%) aquatic participants were diagnosed compared with 89 of 891 (10.0%) non-aquatic participants. For melanoma (MM), 48 out of 512 (9.4%) aquatic participants were diagnosed and 48 of 891 (5.4%) non-aquatic participants, resulting in an odds ratio nearly double (1.8 times) for aquatic participants compared with non-aquatic. Participants of increased age and male gender had an increased likelihood of being diagnosed with MM. Primary locations for KC were the head, face and neck (32% aquatic, 36% non-aquatic), which differed for MM, being primarily located on the back (40% aquatic, 37% non-aquatic). Conclusions While the prevalence of BCC and SCC was similar across activity groups, aquatic participants demonstrated a significantly higher prevalence of MM, despite reporting lower cumulative lifetime UV exposure. A higher MM risk is likely attributable to greater participant engagement during peak ultraviolet radiation (UVR) hours. These findings underscore the need for skin cancer surveillance in aquatic enthusiasts, who should be recognised as a high-risk population within the national melanoma screening framework.