[Epithelioma cuniculatum. Apropos of a case with review of the literature].

A case of Epithelioma cuniculatum arising on a leg ulcer in a 85 years old lady is described. 102 cases have been reported before, mainly located on the sole of the foot: this rare tumor may be recognized by the gross appearance of a slow-growing exophytic cauliflower growth, exuding foul smelling material from numerous sinuses, which eventually invades underlying tissue sometimes including bone, and which rarely metastasizes to the regional lymph nodes. Histological examination shows a well-differentiated squamous epithelial proliferation without cellular atypia, with numerous crypts and sinuses. The diagnosis is difficult as the cytological regularity does not allow malignancy to be evoked. It is the conspicuity of the invasion of the deep tissues with sufficiently large samples that makes it certain. The differential diagnosis includes keratoacanthoma, pseudo-epitheliomatous hyperplasia mainly represented by pyoderma vegetans and "classical" squamous cell carcinoma. From a nosological point of view the authors totally assimilate Epithelioma cuniculatum and Gottron's papillomatosis cutis carcinoïdes regrouped under the name of cutaneous verrucous carcinoma, emphasizing the analogy with verrucous carcinomas of mucous membrane, giant condyloma of Buschke-Lowenstein, oral florid papillomatosis.