A cancer related to racial genetic factors (50-60 cases per 100.000 inhabitants in China, USSR and Japan, and only 10 in Western Europe and in the USA), to food habits (e.g. alcoholism) and to the Plummer-Vinson syndrome. 98% are squamous carcinomas and as opposed to most of these cancers, this one metastasizes very soon through lymphatic and blood spread which accounts for its difficult diagnosis.