CA19-9 is a significant prognostic marker of patients with stage III gastric cancer

Abstract Background Due to prognostic heterogeneity within a stage of gastric cancer (GC), identification of patients with a high risk for recurrence after resection is important. We aimed to identify the prognostic significance of preoperative serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels in patients with Stage I, II, and III GC who underwent R0 gastrectomy. Methods A total of 794 patients were included in this study after excluding 72 patients with CA19-9 Results The optimal cut-off values of CEA and CA19-9 levels were 2.9 ng/mL and 46.3 U/mL, respectively. Multivariate analysis for relapse-free survival (RFS) showed that stage of GC, CA19-9 levels, postoperative adjuvant chemotherapy, and venous invasion were significant independent factors. The RFS and overall survival (OS) of patients with CA19-9 ≥ 46.3 U/mL were significantly lower than those with CA19-9  Conclusions The RFS and OS of patients with CA19-9 ≥ 46.3 U/mL were significantly lower than those with CA19-9