A case of epidermodysplasia verruciformis (Lewandowsky-Lutz, 1922) with skin cancer: histopathology of malignant cutaneous changes.

Histopathology of tumors which occurred on the face of a 34-year-old man with epidermodysplasia verruciformis was studied. The following three different types of histological changes were recognized in the tumors: (1) intraepidermal initial changes; (2) Bowen-like changes, and (3) squamous cell carcinoma. Carcinogenetic processes in this case were compatible with those reported by Todaro et al. in 1966, in which case tumors were caused in vitro by SV40 virus. According to their results, initial transformed cells were observed to occur at the lower layer of the epidermis. It seemed likely that viral infection occurred at the epidermal lower layer and immediately the infected cells divided and some of them changed to transformed cells which then abnormally proliferated to show a malignant feature. Similar histological changes were recognized and viral oncogenesis was suggested in this case too.