Tumor markers in pancreatic cancer. Sensitivity and specificity of CA 19-9

The tumor marker CA 19-9 is based on monoclonal antibody to colonic carcinoma cell lines. In this study, the utility of the tumor marker in the diagnosis of pancreatic carcinoma was evaluated. CA 19-9 is strongly expressed in most tissue specimens obtained from pancreatic carcinomas. However, this antigen is also found in normal pancreas and specimens from chronic pancreatitis. The CA 19-9 is released into the circulation, and was found at increased concentrations (greater than 37 U/ml) in 87% of the patients with pancreatic carcinoma n = 145, as compared with only 13% in the group of patients with benign diseases n = 1,081 and 29% of those with extrapancreatic malignancies n = 691 (P less than 0.0001). The preoperatively raised CA 19-9 concentration in patients with stage I pancreatic carcinoma decreases after curative resection of the carcinoma to values within the normal range. However, in no CA 19-9 estimation following palliative surgical intervention of stage III and IV patients or in cases of inoperable carcinomas was a serum concentration of less than 37 U/ml recorded. Accordingly, the median survival of stage I patients was 29 months, and of stage III, IV and patients with inoperable carcinomas 6 months only.