Cutaneous squamous-cell carcinoma in patients treated with PUVA.
A 5.7-year prospective study of 1380 patients treated for psoriasis with oral methoxsalen (8-methoxypsoralen) and ultraviolet A photochemotherapy (PUVA) revealed that after adjustment for exposures to ionizing radiation and topical tar preparations, the risk that cutaneous squamous-cell carcinoma would develop at least 22 months after the first exposure to PUVA was 12.8 times higher in patients exposed to a high dose than in those exposed to a low dose (95 per cent confidence interval, 5.8 to 28.5). No substantial dose-related increase was noted for basal-cell carcinoma. The dose-dependent risk of cutaneous squamous-cell carcinoma suggests that PUVA can act as an independent carcinogen. In our study, morbidity associated with these tumors has been limited, but further follow-up is needed. Meanwhile, patients treated with PUVA should be followed closely for the possible development of cutaneous squamous-cell carcinoma.
D000328:Adult; D002280:Basal Cell Carcinoma / Q000139:chemically induced / Q000453:epidemiology; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced* / Q000453:epidemiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011701:PUVA Therapy / Q000009:adverse effects*; D010778:Photochemotherapy / Q000009:adverse effects*; D011336:Probability; D011446:Prospective Studies; D011565:Psoriasis / Q000188:drug therapy; D012306:Risk; D012878:Skin Neoplasms / Q000139:chemically induced* / Q000453:epidemiology