Endocrine profile in gastric carcinomas. An immunohistochemical study

22 gastric carcinomas (13 intestinal type and nine diffuse type) were immunostained for neuron specific enolase, chromogranin, Leu-7 and a panel of fifteen different peptide hormones. Five out of the 13 tumours of intestinal type and four out of the nine diffuse carcinomas expressed immunoreactivity for one or more of the pan endocrine markers. Seven out of the 13 tumours of intestinal type and five out of the nine diffuse carcinomas also expressed immunoreactivity for gastrin (3), ACTH (3), serotonin (7) and calcitonin (7). Immunoreactivity for somatostatin (1) and substance P (1) were also seen in two tumours of intestinal type. Seven out of 18 cases with benign mucosa adjacent to the tumours expressed a focal immunoreactivity for chromogranin (6), serotonin (6), gastrin (5) and calcitonin (1). All hormone-producing tumours also expressed immunoreactivity for carcino-embryonic antigen. Our results confirm that a high proportion of gastric carcinomas are hormone producing.