Postoperative Carcinoembryonic Antigen as a Complementary Tumor Marker of Carbohydrate Antigen 19-9 in Pancreatic Ductal Adenocarcinoma

The role of carcinoembryonic antigen (CEA) in pancreatic cancer remains poorly understood. Therefore, this study aimed to determine whether CEA is complementary to carbohydrate antigen 19-9 (CA19-9) in prognosis prediction after pancreatic cancer curative resection. We retrospectively reviewed records of 144 stage II curatively resected pancreatic cancer patients with preoperative and postoperative CEA and CA19-9 levels. Patients with normal preoperative CA19-9 were excluded. R0 resection margin, adjuvant treatment, and absence of angiolymphatic invasion were associated with better overall survival. There was no significant difference in median survival according to preoperative CEA levels. However, patients with normal postoperative CA19-9 (59.8 vs. 16.2 months, P<0.001) and CEA (29.4 vs. 9.3 months, P=0.001) levels had longer overall survival than those with elevated levels. Among 76 patients with high postoperative CA19-9 levels, a better prognosis was observed in those with normal postoperative CEA levels than in those with elevated levels (19.1 vs. 9.3 months, P=0.004). Postoperative CEA and CA19-9 levels are valuable prognostic markers in resected pancreatic cancer. Normal postoperative CEA levels indicate longer survival, even in patients with elevated postoperative CA19-9.