DETECTION OF HUMAN-PAPILLOMAVIRUS DNA IN PUVA-ASSOCIATED NONMELANOMA SKIN CANCERS

Psoralen and UVA (PUVA) photochemotherapy is associated with a dose-de pendent increased risk of nonmelanoma skin cancer in patients treated for psoriasis, Like ultraviolet B radiation, PUVA is both mutagenic an d immunosuppressive and may thus act as a complete carcinogen; however , the reversed squamous to basal cell carcinoma ratio (SCC:BCC) in PUV A-treated patients, also seen in immunosuppressed renal transplant rec ipients, suggests a possible cofactor role for human papillomavirus (H PV) infection, In this study we examine a large series of benign and m alignant cutaneous lesions for the presence of HPV DNA from patients t reated with high dose (greater than or equal to 500 J per cm(2)) ultra violet A. A panel of degenerate primers based on the L1 (major capsid protein) open reading frame was employed, designed to detect mucosal, cutaneous, and epidermodysplasia verruciformis HPV types with high sen sitivity and specificity. HPV DNA was detected in 15 of 20 (75%) non-m elanoma skin cancer, seven of 17 (41.2%) dysplastic PUVA keratoses, fo ur Of five (80%) Skin warts, and four of 12 (33%) PUVA-exposed normal skin samples. The majority of HPV positive lesions contained epidermod ysplasia verruciformis-related HPV including HPV-5, -20, -21, -23, -24 , and -38, Possible novel epidermodysplasia verruciformis types were i dentified in further lesions. Mixed infection with epidermodysplasia v erruciformis, cutaneous, and/or mucosal types was present in six of 30 (20%) of all HPV positive lesions, including in normal skin, warts, d ysplastic PUVA keratoses, and squamous cell carcinomas, The prevalence and type of HPV infection in cutaneous lesions from PUVA-treated pati ents is similar to that previously reported in renal transplant-associ ated skin lesions, and suggests that the role of HPV in PUVA-associate d carcinogenesis merits further study.