Elevated tumor marker CA 19-9 in the differential diagnosis of pancreatic mass lesions.

Inflammatory and neoplastic tumors of the pancreas still remain a diagnostic dilemma for a surgeon mainly due to subtle differences between these two sorts of tumors. The aim of the study was to assess the utility of the serum marker, CA 19-9, in the differential diagnosis of pancreatic tumors. 150 patients with heterogenic pancreatic lesion were diagnosed and treated at 2nd Department of General Surgery, Medical University of Lublin between June 1998 and Dec. 2003. Their age ranged between 26 and 78 years. Based upon cytology and histology, patients were assigned to malignant or benign group. The serum from all the patients was assayed for the CA 19-9 test and sensitivity and specificity of the CA 19-9 test was determined. Finally pancreatic cancer was diagnosed in 98 patients, benign pancreatic lesion in 52 patients. Based upon the serum level of the CA 19-9 true positive results were found in 82 patients, true negative results in 47 patients, false negative results in 16 patients and false positive results in 5 patients. Sensitivity of the CA 19-9 assay was 83.7% and specificity was 90.4%. An elevated serum level of the CA 19-9 in the presence of pancreatic lesions usually suggests malignant nature of the lesion. A high CA 19-9 level is typical of advanced inoperable pancreatic cancer. Taking into account a limited sensitivity and specificity of the CA 19-9 assay, its results should be interpreted in consistency with an analysis of imaging examinations such as US and CT.