Predictive Factors for Elevated Postoperative Carbohydrate Antigen 19-9 Levels in Patients With Resected Pancreatic Cancer

AIM: In this study, we investigated the clinical significance of postoperative serum carbohydrate antigen (CA) 19-9 in patients with pancreatic ductal carcinoma (PDAC). PATIENTS AND METHODS: A series of 116 patients with macroscopically curative PDAC resection was retrospectively evaluated. The cut-off level for elevated postoperative CA 19-9 was 37 U/ml. RESULTS: Patients with high postoperative CA19-9 levels had a significantly poorer prognosis than patients with normal postoperative CA19-9 levels, as revealed by the log-rank test. Multivariate analysis identified R1 resection and preoperative serum CA19-9 level ≥400 U/ml independently predicted elevated postoperative CA 19-9 levels. R1 resection and preoperative serum CA19-9 ≥400 U/ml were significantly associated with the recurrence of peritoneal dissemination and hepatic metastasis, respectively, within one year of operation. CONCLUSION: Elevated postoperative serum CA 19-9 level was associated with a poor prognosis and reflected positive resection margins and high preoperative CA 19-9 levels, which indicated presence of occult distant metastasis in patients with PDAC.