Prediction of recurrence and survival by post-resection CA 19-9 values in patients with adenocarcinoma of the pancreas

Background: CA 19-9 levels are useful for the diagnosis of patients with pancreatic adenocarcinoma. However, interest has recently turned toward its use as a prognostic indicator. The purpose of this study is to determine whether postoperative CA 19-9 levels predict disease-free survival (DFS) and median survival (MS) in patients after resection. Methods: Between 1988 and 1996, 40 patients underwent resection for pancreatic adenocarcinoma and were evaluated with postoperative CA 19-9 assays. Eight patients had low preoperative levels of CA 19-9 (<2) and were excluded. Results: CA 19-9 levels are good predictors of DFS and MS. Patients whose postoperative CA 19-9 values normalized by 3 to 6 months (<37 U/ml) had longer DFS (24 vs. 10 months, p < 0.04) and MS (34 vs. 13 months, p < 0.04). Patients with postoperative CA 19-9 values less than 180 U/ml at 1 to 3 months had a similar DFS (19 vs. 5 months, p < 0.0009) and MS (34 vs. 13 months, p < 0.0001) compared to patients with normal values at 3 to 6 months. Conclusions: Postoperative measurements of CA 19-9 were the best predictors of DFS and MS. Values < 180 U/ml at 3 months were as predictive as normal values by 3 to 6 months postoperatively. Consequently, CA 19-9 levels should be obtained for use as a stratification parameter in phase III trials.