Effectiveness of discriminant analysis of serum CA 19-9 and elastase 1 in diagnosis of pancreatic carcinoma.

The accuracies of assays of serum CA 19-9 and elastase 1 in the diagnosis of pancreatic carcinoma were investigated by the cutoff method and discriminant analysis of data on 98 patients with pancreatitis, 65 patients with pancreatic carcinoma, 107 patients with benign diseases of other organs, and 108 patients with cancer of other organs. Comparison of the diagnostic accuracies of the cutoff method and multivariate analysis of CA 19-9 and elastase 1 showed that the latter was better for diagnosis in terms of its specificity. The performance of multivariate analysis was validated on independent data consisting of 52 patients with pancreatitis, 27 patients with pancreatic carcinoma, 79 patients with benign diseases of other organs, and 29 patients with cancer of other organs. Multivariate analysis of CA 19-9 and elastase 1 was very useful for differentiation of patients with and without pancreatic carcinoma: 24 (88.9%) of 27 patients with pancreatic carcinoma were correctly classified. Moreover, by this method, all patients with pancreatic carcinoma of less than 2 cm in longest diameter and 81.3% of those without jaundice were correctly classified.