A large-scale study integrating CEA and tumor deposits to evaluate prognosis in colon cancer patients.

Background: Reliable prediction of long-term survival in colon cancer remains limited by staging system constraints. CEA and tumor deposits (TD) are known prognostic markers, but their combined predictive value is underexplored. Materials and Methods: We retrospectively analyzed 1, 029 patients with locally advanced colon cancer who underwent radical resection. A CEA-TD scoring system was developed and integrated with key clinicopathologic variables to construct a prognostic nomogram. Results: Both TD(+) and elevated CEA levels were independently associated with significantly worse overall survival (HR for TD = 1.985, CEA = 2.209; all P < 0.01). The CEA-TD score effectively stratified patients into four risk categories, each with distinct survival outcomes (P < 0.001). The final nomogram, incorporating CEA-TD score, T stage, N stage, grade, and tumor location, demonstrated high predictive performance, with AUCs of 0.796, 0.834, and 0.807 for 1-, 3-, and 5-year OS in the training cohort, and comparable values in internal and external validations. The C-index reached 0.800, outperforming traditional prognostic factors. Kaplan-Meier and risk curve analyses confirmed the model's discriminative capacity. Conclusions: The CEA-TD-based nomogram offers accurate, clinically applicable risk stratification for LOCC patients, supporting personalized treatment strategies and improved prognostic assessment.