Tissue CEA detection by immunoperoxidase (PAP) test in colorectal polyps: correlations with the degree of dysplasia

We study the presence of Carcinoembryonic antigen (CEA) on 39 colorectal polyps by the immunoperoxidase technique. The histological examination demonstrated 15 tubular adenomas, one villous adenoma, two tubulo-villous adenomas, six tubular adenomas with slight dysplasia, one tubular adenoma with moderate dysplasia, four tubular adenomas with severe dysplasia, three tubulo-villous adenomas with severe dysplasia, five tubular adenomas with neoplastic degeneration, and two tubulo-villous adenomas with neoplastic degeneration. Twenty-eight of thirty-nine polyps (71.79%) showed a positive staining reaction for CEA. Regarding the intensity of the reaction (classified as absent or negative [-], slightly positive [+], and markedly positive [+ +]), 11/39 polyps presented a negative reaction (28.21%), 19/39 (48.71%) presented a slight reaction, and 10/39 polyps (25.64%) presented a marked reaction. Results demonstrated a higher intensity of the staining reaction in severely dysplastic polyps and in neoplastic degeneration. In conclusion, it is possible that the presence of CEA can be useful to show an initial cellular restlessness of certain polyps.