[Clinical evaluation of the tumor marker CA 19-9 in comparison with carcinoembryonic antigen (CEA) in surgical pre- and postoperative diagnosis].

A new tumor marker (CA 19-9) was investigated. CA 19-9 is a tumor-associated antigen which is detected by a monoclonal antibody. CA 19-9 (CIS-Centocor) was compared simultaneously with CEA (carcinoembryonic antigen) in 347 patients. 123 patients with gastrointestinal tumors showed a sensitivity of 31% for CA 19-9 (CEA 49%), combination increased sensitivity to 58%. The highest sensitivity was found in pancreas carcinoma (CA 19-9 75%, CEA 66%, combination 92%); it was lower in gastric, colon, and oesophagus carcinomas. In relapsed colorectal carcinomas sensitivity was 53% (CEA 78%, combination 85%). In cases of relapse, tumor markers may become positive even if they were not detectable before resection of the primary tumor. Specificity for CA 19-9 was 100% (CEA 84%) compared to a group of non-malignant diseases including patients with inflammations and patients with nicotin abuse (n = 102). Because of its high specificity and superior sensitivity to CEA in pancreas carcinomas CA 19-9 should be determined in primary and relapse diagnosis in combination with CEA.