Nonmelanoma skin cancer in an Irish population: an appraisal of risk factors.

Previous Irish studies have shown a high prevalence of nonmelanoma skin cancer (NMSC). However, unlike elsewhere where the generally quoted ratio of basal cell carcinoma (BCC):squamous cell carcinoma (SCC) is at least 4:1 the ratio in Ireland was found to be 1:1. We examined this ratio in patients attending the dermatology outpatients and determined risk factors for the development of NMSC within an Irish population where 75% of the population have been shown to have skin type 1 or 11. The study consisted of a retrospective 10 year review of biopsy proven cases of NMSC and a prospective case control study of NMSC which allowed examination of risk factors and comparison to a control group. The BCC:SCC ratio in the retrospective study was 3:1. In the prospective study the ratio of BCC:SCC was 4.4:1. Skin type 1 and numerous freckles were identified as risk factors in the NMSC group.