Relationship between prognostic impact of N3 lymph node metastasis at the root of the feeding artery and location of colon cancer

PurposeTo determine whether N3 nodal involvement predicts outcomes and whether its prognostic implications vary with tumor location in patients with Stage III colon cancer (CC).MethodsWe defined N3 as lymph node metastases near the bases of the major feeding arteries. We retrospectively examined recurrence rates and patterns by tumor location and sites of lymph node metastases in 57 patients with N3 CC who had undergone curative resections between January 2000 and March 2019. Survival analysis was performed to compare the prognoses of patients with and without N3 lymph node metastasis.ResultsMost N3 patients had large tumors (T >= 3); five had T2 disease. Recurrence occurred quickly in one patient with T2N3M0 disease. Multivariate survival analysis demonstrated that N3 lymph node metastasis is an independent predictor of poor prognosis in Stage III CC patients (P < 0.001). Categorizing N3 patients according to UICC-TNM staging system does not stratify risk of recurrence (P = 0.970). To investigate the impact of tumor location on recurrence risk, we classified N3 CC into two subtypes according to tumor location: metastasis at the base of the superior mesenteric artery in right-sided CC and inferior mesenteric artery in left-sided CC. The former was found to have a statistically significant poorer prognosis than the latter (P = 0.091).ConclusionN3 is a robust prognostic marker in CC patients. Recurrence risk varies by tumor location. N3 right-sided CCs with lymph node metastasis at the base of the superior mesenteric artery have poorer prognoses than do N3 left-sided CCs.

Automated summary

This study aims to determine the predictive value of N3 nodal involvement in patients with Stage III colon cancer (CC) and whether its prognostic implications vary with tumor location. The results showed that N3 lymph node metastasis is an independent predictor of poor prognosis in Stage III CC patients, and the risk of recurrence varies by tumor location, with N3 right-sided CCs having poorer prognoses than N3 left-sided CCs.