Atypical gastric carcinoids.

Four examples of infiltrating gastric tumours which had light microscopic features suggestive of carcinoid or oat-cell carcinoma are documented. Histological and ultrastructural findings indicated that these tumours were atypical carcinoids. A spectrum of endocrine cell neoplasia in the stomach analogous to that observed in the bronchus is postulated. It is felt that increased recognition of poorly differentiated endocrine tumours of the stomach might be of prognostic and therapeutic importance.