Seborrheic keratosis-like lesions in epidermodysplasia verruciformis.

A light microscopic study of 6 verrucous lesions with clinical features of seborrheic keratoses (SK) occurring on sun-exposed skin of 4 patients with epidermodysplasia verruciformis (EV) was performed. We observed the typical histological findings of SK in all cases. In addition, koilocytotic effects suggestive of EV were observed in the upper prickle layer and stratum granulosum. In 2 lesions, we also noted bowenoid changes suggesting possible early malignant transformation. Immunohistochemical study confirmed the presence of HPV in these lesions.