Histopathology of gastric carcinoids: a survey of 42 cases

Abstract

An unselected series of 42 gastric carcinoids [human] was reviewed. Clinically the tumors simulated common gastric lesions including ulcer, polyp and carcinoma. No endocrine symtpoms were identified. The tumors were most frequent in the body of the stomach and 25% in that site were multiple. Morphologically, most tumors classified according to Soga demonstrated a mixed growth pattern. Six tumors displayed an atypical morphology (type D): they were larger and metastasized more frequently than the rest of the tumors. Six tumors contained a few scattered argentaffinic cells, but the others were negative, indicating negligible serotonin secretion in only a few cases. The Grimelius argyrophilic reaction was positive in most cells in all but 3 tested tumors, 2 of which showed atypical morphology (type D). Gastric carcinoids with a type D morphology or a minority cell population of argyrophil cells are dedifferentiated carcinoids which are biologically nearer to gastric carcinomas. The most frequent clinicopathological correlation was achlorhydria, linking pernicious anemia and gastric carcinoids. This indicates pathogenetic similarities between gastric carcinoids and gastric carcinomas.