[Expression and secretion of carcinoembryonic antigen in tumors of the large intestine].

The correlation between the expression of the carcinoembryonic antigen (CEA) on cell membranes and the intensity of its secretion into the circulation is studied in patients with malignant tumours of the rectum and the transverse colon. With the use of the monoclonal antibodies against CEA and the immunoperoxidase technique on the frozen sections, the localization of the primary tumour, microinvasion and micrometastases in the lymph nodes are shown. The dependence of the serum CEA concentration upon the histologic type of the tumour and the stage of the disease is not established. The trend towards the inverse correlation between the CEA level in the tumour tissue extract and the degree of the tumour cell differentiation is noted. The opinion is expressed of the applicability of the monoclonal antibody anti-CEA-1 for the morphologic differential diagnosis of the colon tumours, the evaluation of the thoroughness of the surgical treatment and for the metastases radioimmunolocalization.