Verrucous carcinoma of skin.

Five different cases of verrucous proliferative lesions of skin are described and discussed. One of each developed in a chronic ulcer on a heel, in a scar on a lower leg, and on the penis, and two appeared in the region of the buttock in relation to chronic inflammatory sinuses. All these lesions showed morphological and clinical features of verrucous carcinoma which are described. It has been concluded that the variously named verrucous lesions in the literature (epithelioma cuniculatum, florid papillomatosis, giant cutaneous papilloma and papillomatosis cutis carcinoides), as well as our five cases represent a verrucous carcinoma which is a particular type of squamous cell carcinoma. This tumor develops typically in moist areas which are frequently sites of chronic inflammation. Despite the favorable prognosis, it is a potentially invasive tumor.