Prognostic Factors in Colon Carcinoma: Correlation of Serum Carcinoembryonic Antigen Level and Tumor Histopathology

The results of histopathologic study and the preoperative circulating carcinoembryonic antigen levels were correlated with each other and with the postoperative clinical course in 45 surgically treated patients with cancer of the colon. Histopathologic evaluation of the tumor included the depth of bowel wall involvement according to the Dukes classification, the histologic differentiation of cells on the basis of Broders' grades of malignancy, evidence of lymphocyte and plasma cell infiltration within and surrounding the primary tumor, and evidence of blood vessel, lymphatic, and perineural invasion. All these parameters, including the serum carcinoembryonic antigen level, had prognostic value. Low serum carcinoembryonic antigen levels in patients with colonic cancer suggested tumor localized within the bowel wall; the highest values were found in patients with tumors that had spread beyond the bowel wall. An inverse correlation was noted between the degree of tumor differentiation and carcinoembryonic antigen levels in the same patient. Carcinoembryonic antigen levels tended to be elevated when blood vessel, lymphatic, and perineural invasion was present. An inverse correlation was also noted between the preoperative carcinoembryonic antigen level and the degree of lymphocyte and plasma cell infiltration in the primary tumor. Round cell infiltration was interpreted as an indication of the host's immune response against the tumor. Thus, on the basis of clinical follow-up of the patients it is concluded that all morphologic parameters evaluated have prognostic value, that preoperative serum carcinoembryonic antigen levels have prognostic value, that all prognostic parameters correlate with each other appropriately, and that the combined parameters are more reliable than any single one alone.