Prognostic value of serum CEA and CA19-9 levels in pancreatic ductal adenocarcinoma

Abstract

The present study investigated the associations of serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) levels with clinicopathological variables and survival outcomes in Libyan patients with pancreatic ductal adenocarcinoma (PDAC). The clinicopathological variables of 123 patients with PDAC registered at the National Cancer Institute in Misurata, Libya, between 2010 and 2018 were retrospectively analyzed. Blood samples from these patients were analyzed for serum CEA and CA19-9 levels before treatment by electrochemiluminescence immunoassay (double antibody sandwich ELISA) on a Roche cobas e 602 modules. The relationships between CA19-9 and CEA serum levels with clinicopathologic variables and survival outcomes were analyzed using the Kaplan-Meier method, log-rank test and Cox regression analyzes. Cut-off values for serum CEA and CA19-9 levels were 5 ng/ml and 400 U/ml, respectively. The median serum levels of all patients with PDAC for CEA and CA19-9 were 8 ng/ml (1.1-377 ng/ml) and 389 U/ml (1-10,050 U/ml), respectively. Tumors with higher serum CEA and CA19-9 levels were found in 63 and 48% of patients, respectively. Higher CEA and CA19-9 serum levels were significantly associated with more indicators of a malignant phenotype, including a surgically unresectable tumor, unevaluable lymph nodes, advanced stages and distant metastases. Regarding survival, patients with higher serum levels of the biomarkers CEA and CA19-9 had shorter overall survival rates (P<0.016 and (P<0.014, log-rank, respectively) and lower disease-free survival rates (P<0.002 and P<0.0001, log-rank, respectively). The present study demonstrated significant clinical and prognostic value of serum levels of biomarkers CEA and CA19-9 for Libyan patients with PDAC. Moreover, patients with PDAC with higher serum CEA and CA19-9 levels had more aggressive tumors, higher rates of disease recurrence and shorter overall survival rates and thus required more vigilant follow-up. Further multinational studies with larger PDAC cohorts are warranted to confirm these findings in terms of improved clinical decision making, more effective management and improved survival.

Keywords: ELISA; carbohydrate antigen 19-9; carcinoembryonic antigen; expressions; pancreatic ductal adenocarcinoma; prognosis; survival outcomes.

Figure 1

OS according to analysis of CEA expression and CA19-9 in pancreatic adenocarcinoma (Kaplan-Meier curves). (A) CEA level at cut point of 5 ng/ml. (B) CA 19-9 level at cut point of 400 U/ml. OS, overall survival; CEA, carcinoembryonic antigen; CA19-9, carbohydrate antigen.

Figure 2

DFS according to analysis of CEA expression and CA19-9 in pancreatic adenocarcinoma (Kaplan-Meier curves). (A) CEA level at cut point of 5 ng/ml. (B) CA 19-9 level at cut point of 400 U/ml. DFS, disease free survival; CEA, carcinoembryonic antigen; CA19-9, carbohydrate antigen.