Serum CEA, CA 15-3, and MCA in breast cancer patients: a clinical evaluation.

With the aim of investigating the clinical usefulness of CEA, CA 15-3, and MCA serum levels, we studied 143 women whose breast cancer was submitted to serial tumor marker determinations: 79 women had stage I-II tumors and were undergoing follow-up after local and adjuvant treatment; 64 women presented metastatic lesions. Among the stage I-II patients, 63 women remained disease-free during the observation period and 16 developed metastases. In 13 out of 16 patients, tumor markers were elevated and in 11 out of 16 patients the increased tumor markers were the first sign of disease progression. Among metastatic patients, 49 presented increased tumor markers and 15 normal value. Moreover, we observed a decrease or normalization of tumor markers in patients responding to treatment and increased values in progressive disease. No correlation was noted between site of disease and tumor markers. We concluded that tumor markers are of clinical value in the detection of metastasis and may be useful in monitoring response to treatment in metastatic patients.