Clinical evaluation of combined use of CEA, CA19-9 and CA50 in the serum of patients with pancreatic carcinoma.

CEA, CA19-9 and CA50 are tumour-associated antigens defined by monoclonal antibodies that have been raised against adenocarcinoma cell lines, but no single antibody is specific for the detection of pancreatic malignancy. The aim of this study was to determine whether the combined use of CEA, CA19-9 and CA50 would improve diagnostic accuracy. An immunoradiometric assay was used for the detection of CEA and CA19-9 and the Delfia system for CA50. Serum was collected from 65 normal subjects, 16 with pancreatitis and 28 with pancreatic carcinoma. Of the 28 cancer patients, 24 (85%) had a CA19-9 level above 46 mu/ml, 26 (92%) had a CA50 level above 21 mu/ml and 10 (37%) had a CEA level above 7 ng/ml. Multivariant discriminant analysis on the combined antibodies showed that 96% of the malignant group, 13% of the pancreatitis group and 11% of the normal group were positive, with an overall correct classification of 91% into the three groups (multivariant discriminant analysis P less than 0.05). Thus the combined use of CEA, CA19-9 and CA50 improves diagnostic accuracy in differentiating benign from malignant disease of the pancreas.