[Carcinoma cuniculatum. Apropos of 4 cases with orofacial involvement].

Carcinoma cuniculatum, a rare variant of verrucous carcinoma, was first described in the foot. The authors report 4 cases of uncommon localizations of this tumor, involving oral cavity and face, 3 of them having a 6-year follow-up. The specific histological and clinical features of this tumor are remembered and the difficulties of its diagnosis are emphasized. This slow-growing, ulcerated proliferation, invading the surrounding tissues, is often responsible for chronic suppuration, but very rarely metastasizes to the regional lymph nodes. The surgical treatment consists in a wide excision; neck dissection is theoretically useless, and radiotherapy is strictly contraindicated because of the risk of transformation into an anaplasic carcinoma. For all these reasons, carcinoma cuniculatum must be considered as an anatomoclinic entity, and deserves to be known by the clinicians and the pathologists.