Objective: To see if tumour associated antigens CA 195 and CA 19-9 were able to differentiate between patients with pancreatic carcinoma, and those with chronic pancreatitis or stones in the common bile duct.
Design: Prospective, open, clinical study.
Setting: 47 patients with histologically confirmed pancreatic adenocarcinoma, 38 with chronic pancreatitis diagnosed by endoscopic retrograde cholangiopancreatography (ERCP), and 26 with stones in the common bile duct diagnosed and treated by ERCP.
Interventions: Samples of serum taken from all patients just before ERCP, and samples of pancreatic juice obtained from 18, 11, and 12 patients, respectively during ERCP.
Results: Assay of the two tumour markers in pancreatic juice failed to differentiate between patients with benign and malignant disease. When assayed in serum, however, CA 195 detected those with carcinoma with a sensitivity of 72% and a specificity of 92%, and CA 19-9 with a sensitivity of 81% and a specificity of 88%. The patients with unresectable tumours had significantly higher concentrations of both markers in serum than patients with resectable tumours (p less than 0.05).
Conclusions: CA 195 and CA 19-9 concentrations in serum are equally successful in differentiating between benign and malignant pancreatic disease. Assay of markers in pancreatic juice does not provide useful diagnostic information.