Involvement of human papillomavirus type 20 in epidermodysplasia verruciformis skin carcinogenesis.

The involvement of human papillomavirus (HPV) in skin carcinogenesis in a patient with epidermodysplasia verruciformis was studied. This patient had disseminated pityriasis versicolor-like lesions, flat warts, and a malignant skin carcinoma. HPV types 3, 17, 20 (HPV-20), and 38 were isolated and molecularly cloned from the benign skin lesions of this patient. Of these HPVs, only HPV-20 was detected in the malignant skin carcinoma. Transcripts of HPV-20 were also expressed in the carcinoma. These findings suggest that HPV-20 was involved in the skin carcinogenesis in this patient.