Carcinoembryonic antigen detection by immunocytochemical methods in carcinomas of the colon and stomach.

CEA was studied in paraffin sections from 50 cases of colonic and 50 cases of gastric adenocarcinoma using immunoperoxidase and immunofluorescence techniques. CEA was positive more frequently in colonic (86 per cent) than in stomach carcinoma (76 per cent). Immunoperoxidase was found to be the more sensitive technique for the detection of CEA in both organs. The non-neoplastic peritumoral colonic mucosa was more often CEA positive than was the peritumoral gastric mucosa. CEA was found more often, and the intensity of the staining was stronger in well-differentiated colonic and gastric carcinoma than it was in poorly differentiated carcinoma. No relation was found between the presence of CEA in colonic and gastric carcinoma and the stages of the disease. CEA was detected more frequently in carcinomas of the left colon than in carcinomas of the right colon.