[Cancer formation in a hyperplasiogenic gastric polyp (author's transl)].

Patients carrying hyperplasiogenic polyps are considered to be a higher risk in regard to carcinogenesis, since a high incidence of cancer has been demonstrated in this group. Usually cancers however originated in other parts of the stomach wall and not in the polyps. Formation of cancer in a polyp is a very rare event. A case report is given of a patient carrying a hyperplasiogenic polyp from which originated cancer. Carcinogenesis is discussed from a formal and causal point of view.