Human chorionic gonadotropin in colorectal carcinoma. An immunohistochemical study.

To assess the biological significance of human chorionic gonadotropin (HCG) detection in large bowel carcinomas, we have studied immunohistochemically 50 colorectal carcinomas, 20 adenomas, 8 ulcerative colitis, and 10 normal colonic mucosae. The HCG-immunoreactive cells were found in 26 carcinomas (52%). Positivity was not detected in any normal mucosa or benign lesions. Cells containing HCG predominated in mucinous (80%) and poorly differentiated carcinomas (92%). No trophoblastic differentiation could be demonstrated in any tumor. Human chorionic gonadotropin was detected more frequently in carcinomas invading the entire bowel wall (67%) than in those confined to the submucosa or muscularis propria (30%). Fifteen of 19 cases (79%) with lymph node and/or hepatic metastases had HCG in the primary tumor, whereas only 9 of 23 cases (32%) without metastases showed HCG immunoreactivity. The eight patients with hepatic metastases had HCG in the primary tumor. Thus, the immunohistochemical detection of HCG in colorectal carcinomas may be a biological marker of prognostic significance.