Use of serial carcinoembryonic antigen assays in detecting relapses in breast cancer involving high risk of metastasis

Abstract Serial CEA assays on serum using the direct radioimmunoassay method (Marcoule, France) were performed on 76 breast cancer patients with node involvement or rapid local development of tumors who were undergoing chemotherapy. The patients were followed up for a mean period of 28 months , and assays were repeated every 2.5 months on average. Out of 521 assays performed on 49 patients who remained in complete remission, there were 37 instances of significant, but transitory, rise in CEA level which, in 8 cases, could be attributed to intercurrent benign inflammation. In 15 out of 27 patients who had relapses, there was a significant and persistent rise in CEA level which, in 11 cases, preceded clinical signs by 6 months on average. In the 12 other cases, CEA level remained constant and normal despite relapse.