In series of 248 gastric carcinomas from surgical resections the occurence of argyrophil and argentaffin cells was studied. These cells were distinctly more frequent in diffuse than in tubular carcinomas. In all cases with both types of APUD-cells, argyrophil cells were more numerous than argentaffin cells. These tumors are considered to be a variant of current gastric carcinoma, with more pronounced APUD-differentiation of neoplastic cells. This variant stands apart from carcinoid tumors and also from those rare nasal adenocarcinomas with argentaffin cells.