High Preoperative CA 15-3 Concentrations Predict Adverse Outcome in Node-Negative and -Positive Breast Cancer: Study of 600 Patients with Histologically Confirmed Breast Cancer

Background: CA 15-3 is the most widely used serum marker in breast cancer. Currently, its main uses are in the surveillance of patients with diagnosed disease and monitoring the treatment of patients with advanced disease. Methods: Preoperative CA 15-3 concentrations were measured prospectively in 600 patients with histologically confirmed breast cancer. Marker concentrations were related to patient outcome by both univariate and multivariate analysis. Results: After a median follow-up of 6.27 years, patients with high preoperative concentrations of CA 15-3 (>30 units/L) had a significantly shorter overall survival pattern than those with low concentrations. As a prognostic factor, CA 15-3 was independent of tumor size, axillary node status, and patient age. As well as being prognostic in the total population of patients, CA 15-3 also predicted outcome in different subgroups of patients, including those with both node-negative and node-positive disease, those who were both estrogen receptor (ER)-negative and ER-positive, and those younger and older that 50 years of age. CA 15-3 was also predictive of outcome irrespective of the type of adjuvant therapy administered, i.e., whether adjuvant hormone therapy, adjuvant chemotherapy, or radiotherapy was administered. Conclusion: Assay of CA 15-3 is a relatively inexpensive, convenient, and noninvasive method for evaluating prognosis in newly diagnosed breast cancer patients. © 2004 American Association for Clinical Chemistry