Prognostic Value of Tumor Deposits in Stage III Colorectal Cancer Patients with Different N Stages: A Population-Based, Retrospective, Cohort Study

Purpose Tumor deposits (TDs) seem to be associated with the prognosis of patients with colorectal cancer (CRC). The goal of this study was to investigate the prognostic value of TDs among patients with stage III CRC at different N stages. Methods A retrospective analysis was performed on two independent cohorts of stage III CRC patients from the Surveillance, Epidemiology, and End Results (SEER) database ( n = 8232) and the First Affiliated Hospital of Wenzhou Medical University ( n = 423). Primary outcomes were overall survival (OS) and cancer-specific survival (CSS). Results Of 8232 patients in the SEER cohort, the presence of TDs revealed poorer 5-year OS rates and 5-year CSS rates in all N-stage subgroups. X-tile software identified 5 (5-year OS: P = 0.004; 5-year CSS: P < 0.001) as the optimal cutoff value for TD count in the TD-positive subgroup at the N2 stage. The OS (5-year OS: 62.0% vs. 42.0%, P < 0.001) and CSS (5-year CSS: 66.0% vs. 43.8%, P < 0.001) of patients with five or more TDs were significantly worse than those with one to four TDs in the N2 stage subgroups. Of 423 patients in the Wenzhou cohort, the 3-year OS rate for patients in the positive group was worse than that for patients in the negative group (88.7% vs. 94.3%, P = 0.015). Conclusions TD count should be considered when evaluating the prognosis of patients with the N2 stage. Those with higher TD counts (≥ 5) might have a worse prognosis.