Trends in the incidence of nonmelanoma skin cancer of head, neck, and face in Southern Thailand.

Skin cancer incidence in the head, neck, and face, which are areas with high ultraviolet radiation exposure, remains unclear. We aimed to determine skin cancer incidence and project future trends in southern Thailand based on the Songkhla Cancer Registry (1989 and 2015). Age-standardized incidence rates for nonmelanoma skin cancers (NMSCs) were predicted to 2030 using the Joinpoint, age-period-cohort, and NordPred models. Population zones were divided based on occupation and ultraviolet radiation exposure. In total, 750 patients were diagnosed with NMSC of the head, neck, and face, including 546 and 204 cases of basal cell carcinoma and squamous cell carcinoma (SCC), respectively. The age-standardized incidence rates in 1989 and 2015 were 1.00 and 2.47 per 100,000 persons/year, respectively. The projected value was 2.00 per 100,000 persons/year in 2030. NMSC rates in women who worked in cities decreased (annual percent change = - 2.3, p < 0.001). SCC rates in women working at rubber plantations decreased (annual percent change = - 4.7, p < 0.001). Overall, NMSC incidence was constant; however, reductions were observed in women working in cities and at rubber plantations. Thus, our methodology estimated NMSC incidence in women and its association with reduced ultraviolet radiation exposure.