Verrucous carcinomas are lesions occurring mainly in the buccal mucosa but sometimes they arise also in the larynx. The disease is characterized by a cornifying verrucous proliferation of the squamous epithelium, without atypias or metastases. The clinical and histological pictures of six observations are described and the differential diagnosis from hyperkeratotic papillomas and benign keratosis of the larynx are discussed. In one of these cases, 13 years after the beginning of the disease a focal cancerisation could be observed. The authors consider this disease not as a carcinoma and are not sure whether it is a true tumor at all. They propose therefore the name "verrucous acanthosis" instead of verrucous carcinoma and classify these lesions as facultative precanceroses.