Genital squamous cell carcinoma in men treated by photochemotherapy. A cancer registry-based study from 1978 to 1998.

Background: One single report from the U.S. 16-centre-trial indicated that psoralen and ultraviolet A radiation (PUVA) therapy may induce an increased risk of genital tumours in men, and protection of the genital area is, therefore, recommended.
Objectives: To evaluate the relevance of this risk in routine clinical practice.
Methods: Two groups of patients were included in a 1978-98 retrospective study. Case records of men with genital squamous cell carcinoma (SCC) identified from the Cancer Registry of the Doubs area of France were examined for a history of PUVA therapy, topical tar treatment, psoriasis, human papillomavirus infection or genital dermatitis. In addition, all the dermatologists of the Doubs area (in public and private practice) using PUVA therapy were asked to provide information on the number of patients having received PUVA therapy and whether the genital area was exposed during treatment.
Results: Between 1978 and 1998, among the 48 men who had developed a genital SCC in the Doubs area, only one had a history of intensive PUVA therapy. About 150,000 treatments with PUVA therapy had been performed by 15 dermatologists in the Doubs area for 5400 patients since 1978. No case of genital SCC had been reported, despite the fact that the genital area had not been protected during UVA exposure.
Conclusions: Although retrospective, our study demonstrates that the occurrence of genital SCC in men treated with PUVA therapy is a very rare event in common dermatological practice.