MAMMARY SERUM ANTIGEN (MSA), CA-15-3 AND CEA IN PREOPERATIVE SERA OF BREAST-CANCER PATIENTS AND CORRELATIONS WITH PROGNOSTIC FACTORS

Mammary Serum Antigen (MSA) is a mucin like glycoprotein which is expr essed in numerous breast carcinomas and can be determined using the mo noclonal antibody 3E1.2. Previously a higher preoperative sensitivity of MSA compared to CA 15-3 and CEA was reported. The aim of our study was the comparison of MSA and the established tumor markers CA 15-3 an d CEA in primary breast cancer patients and the correlation to establi shed prognostic factors. Serum levels of 119 patients with primary bre ast cancer were analyzed by immunological techniques. The highest sens itivity of 30,2 % we received for MSA (cut off=55 U/ml) compared with 10,7 % for CEA (cut off=6 ng/ml) and 20,5 % for CA 15-3 (cut off=25 U/ ml). Significant correlations were found between MSA-concentrations an d grading (p=0,006), tumor size (p=0,005) and metastases (p=0,03). No correlations were found between MSA values and tumor type, hormone rec eptors, lymph node status and cathepsin D. MSA is a valuable marker wi th the highest preoperative sensitivity of the three tumor associated antigens.