The Use of Adjusted Preoperative CA 19-9 to Predict the Recurrence of Resectable Pancreatic Cancer

Background: Despite the usefulness of CA 19-9 in the diagnosis and prognosis of pancreatic cancer, cholestasis can falsely elevate CA 19-9 levels, which contributes to limited clinical utility in patients with biliary obstruction. This study was designed to evaluate the usefulness of adjusted preoperative CA 19-9 levels in predicting a prognosis of pancreatic cancer. Methods: The available medical records of patients with resected pancreatic cancer from January 1990 to June 2005 were retrospectively viewed at Yonsei Medical Center, Seoul, Korea. The adjusted CA 19-9 value was obtained by dividing the serum CA 19-9 level by the values of serum bilirubin in case of bilirubin ≳2 mg/dL. Disease-free survival was evaluated according to the adjusted preoperative CA 19-9 value. Results: Sixty-one patients were investigated. Their adjusted preoperative CA 19-9 values were significantly different from the actual baseline CA 19-9 value (129.4 ± 225.2 U/mL, versus 442.1 ± 645.5 U/mL, P < 0.0001). On univariate analysis, peripancreatic microscopic invasion (P = 0.0142), lymphovascular invasion (P = 0.0038), and adjusted preoperative CA 19-9 ≥ 50 U/mL (P = 0.0049) were predictive factors for cancer recurrence after curative resection. Adjusted preoperative CA 19-9 ≥ 50 U/mL (Exp (B) = 2.097, P = 0.027) was an independent predictive factor in multivariate analysis. Conclusions: The adjusted preoperative CA 19-9 value can predict the risk of recurrence after curative resection of pancreatic cancer. Interpreting the preoperative CA 19-9 value adjusted to the serum bilirubin values seems to be more reasonable in evaluating prognosis of pancreatic cancer.