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 (r-CEA) 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.The change between p-CEA and r-CEA could further indicate post-relapse survival, thereby facilitating the assessment of mortality risk stratification in stage I-III CRC patients experiencing metastatic relapse.