Association of preoperative and recurrent serum carcinoembryonic antigen and outcome of colorectal cancer patients with metastatic relapse

Background: Seldom have the associations of preoperative CEA (p-CEA) and recurrent CEA (rCEA) levels as well as changes in p-CEA and r-CEA with survival in patients with stage I-III colorectal cancer (CRC) who have experienced metastatic relapse, been thoroughly examined. Methods: 241 consecutive patients with stage I-III CRC who experienced metastatic relapse at Fudan University Shanghai Cancer Center (FUSCC) between January 2008 and January 2016 were investigated. The influence of p-CEA, r-CEA and CEA alteration on the overall survival (OS) and relapse -to -death survival (RDS) was evaluated. The restricted cubic spline regression model was employed to explore the optimal cut-off value of CEA. Results: All 241 patients were categorized into four groups built on their CEA alteration patterns as follows: A, patients presenting elevated p-CEA levels but normal r-CEA levels (P-N); B, patients displaying normal levels of both p-CEA and r-CEA (N-N); C, patients exhibiting elevated levels of both p-CEA and r-CEA (P-P); D, patients with normal p-CEA levels but elevated r-CEA levels (N-P). The correlation between p-CEA and OS (P = 0.3266) and RDS (P = 0.2263) was insignificant. However, r-CEA exhibited a significant association with both OS (P = 0.0005) and RDS (P = 0.0002). Group A demonstrated the longest OS and RDS, whereas group D exhibited the poorest OS and RDS outcomes. For both OS and RDS, the CEA alteration groups served as an independent prognostic indicator. The optimal cut-off threshold for CEA was determined to be 5.1 ng/ml via the restricted cubic spline regression model. Conclusion: r-CEA has a stronger correlation with OS and RDS in individuals with stage I-III CRC who have experienced metastatic relapse.