Reappraisal of preoperative carcinoembryonic antigen levels as a prognostic factor in resectable colorectal cancer.

Preoperative carcinoembryonic antigen levels in sera were measured in 124 cases of primary colorectal cancer, and their usefulness as a prognostic factor were evaluated. There were no significant differences in the CEA levels with regard to age, sex, size of the primary tumor, histological differentiation, peritoneal dissemination or DNA ploidy, but CEA levels were significantly higher in patients with liver metastasis. By using Cox proportional hazard model, the most significant discriminant in prognosis was liver metastasis, followed by preoperative CEA level, depth of invasion and DNA ploidy pattern. Preoperative CEA measurements were applied as a parameter of biological behavior of colorectal cancer in the follow-up course.