Effect of Tumor Deposits on Overall Survival in Colorectal Cancer Patients with Regional Lymph Node Metastases

Objectives: The staging system of the International Union Against Cancerconsiders tumor deposits to be N1c in patients with no regional lymph node metastasis, butthe significance of tumor deposits in patients with regional lymph node metastases isunclear. We investigated the effect of tumor deposits on overall survival in colorectalcancer patients with regional lymph node metastases.Patients and Methods: From 2000 to 2008, 551 patients underwent resectionsfor colorectal cancer at our medical center. We excluded 87 patients who had distantmetastases or had received neoadjuvant chemotherapy or radiotherapy from our study andstatistically analyzed the remaining 464 patients.Results: Stepwise multivariate Cox proportional hazards analysis in patientswith regional lymph node metastases showed only tumor deposits to be significant foroverall survival (hazard ratio: 2.813; P = 0.0002). Recurrence was seenin 49.2% of patients with tumor deposits (30/61) compared with 14.4% of patients withoutthem (58/403; P < 0.0001). Tumor deposits did not show the same effecton overall survival as lymph node metastases.Conclusions: Tumor deposits were significantly associated with pooreroverall survival in colorectal cancer patients with regional lymph node metastases. Theeffect of tumor deposits on overall survival was between that of lymph node metastasis anddistant metastasis.