Immunohistochemical demonstration of carcinoembryonic antigen in normal, transitional and inflamed colonic mucosa.

Carcinoembryonic antigen (CEA) had been demonstrated immunocytochemically in normal colorectal mucosa (resection margins of colonic carcinomas), in transitional mucosa (mucosa adjacent to carcinomas), in non-specific proctitis and colitis, and in ulcerative colitis. In the resection margins and in non-specific proctitis and colitis, specific CEA staining is generally observed at the surface epithelium. In transitional mucosa, CEA staining is most intense in branching crypts and at the base of the crypts. In ulcerative colitis, areas with regenerative activity as well as precancerous or cancerous specimens exhibit an intense CEA positive membrane straining. In conclusion, colonic tissue with a high proliferative activity, such as transitional mucosa and ulcerative colitis, show a more intense CEA staining than normal colonic tissue. Moreover, the staining pattern is different in proliferating tissues as compared to normal tissue. A pronounced membrane staining in ulcerative colitis indicates rather a higher proliferative activity than cancer or precancer.