CA 19-9 and carcinoembryonic antigen in pancreatic cancer diagnosis.

CA 19-9 (Centocor, Malvern, PA) and carcinoembryonic antigen (CEA), two recently developed immunoradiometric assays utilizing monoclonal antibodies, were evaluated in the sera of 139 subjects in order to assay their individual and combined value in pancreatic cancer diagnosis and to assess the influence of jaundice. Sensitivity, specificity, and accuracy in detecting pancreatic cancer were 69%, 85%, and 54% for CA 19-9; and 28%, 78%, and 6% for CEA, respectively. Combined evaluation gave the highest specificity (95%) when both, and the highest sensitivity (79%) when at least one, gave pathologic results. The receiver-operating characteristic curves demonstrated that CA 19-9 is more discriminating than CEA, for any serum value. A correlation between serum bilirubin and CA 19-9 was demonstrated in pancreatic and extrapancreatic disease. CEA determination, performed using monoclonal antibodies, seems to be unsatisfactory as compared to CA 19-9 in pancreatic cancer diagnosis, and combined assessment does not improve the results of CA 19-9 alone. Jaundice may influence serum CA 19-9 in pancreatic and extrapancreatic diseases.