Comparison of different lymph node staging systems for predicting prognosis in patients with colon cancer who have undergone surgical resection.

At present, the most widely used lymph node (LN) staging system in colon cancer is number of metastatic LNs in pathological assessment (pN) from the 8th edition of the TNM American Joint Committee on Cancer/Union for International Cancer Control staging system, which considers the number of metastatic LNs, omitting the total number of dissected LNs. The aim of the present study was to compare the prognostic performance of pN with alternative LN staging systems, including LN ratio (LNR) and log odds of positive LNs (LODDS). The clinical and histopathological data of 298 patients with colon cancer who underwent elective surgical resection in a single surgical centre were analysed. LNR and LODDS cut-off values according to two previous studies were selected to separate patients into different subgroups. Univariate and multivariate analyses were performed to distinguish prognostic factors. The three-step multivariate analysis showed that LNR was a superior prognostic indicator compared with pN and LODDS. Additionally, the Akaike Information Criterion, a measure of the relative quality of statistical models, confirmed that LNR displayed the best prognostic performance. Similarly, in a subpopulation of patients with number of dissected LNs (NDLN) ≥12, LNR was the most accurate LN staging system in relation to prognosis. In a subpopulation with NDLN <12, there was no significant difference in LN classification prognosis of 5-year overall survival; however, LNR and LODDS were more independent of NDLN than pN. Among the three LN classifications, LNR is the most accurate LN staging system for predicting prognosis for patients with colon cancer who have undergone surgical resection, particularly those with metastatic LNs subjected to adequate lymphadenectomy.