Lymph node ratio as a prognostic factor in gastric cancer patients following D1 resection. Comparison with the current TNM staging system.

INTRODUCTION

Nodal ratio (NR) has been demonstrated to be an independent prognostic factor in patients with gastric cancer. We evaluated the prognostic role of NR comparing it with the current TNM (2010) classification in gastric cancer patients treated with curative (R0) D1 resection.

MATERIALS AND METHODS

We retrospectively reviewed 110 patients who underwent R0 resection for gastric cancer at University Hospital of Larissa between 2002 and 2011. All patients had a D1 lymphadenectomy plus the nodes along the left gastric artery. Factors affecting survival as well as correlations between the N status, NR status and resected nodes were investigated.

RESULTS

In univariate analysis the N and NR status but not the numbers of retrieved nodes were significant prognostic factors. Inside N1 and N2 categories, patients with different NR groups were present and survival of some of these subpopulations was statistically different at long-rank test. There was a correlation between the nodes retrieved and N status but not with the NR category. In multivariate analysis both N status (HR=1.45; 95% C.I. = 1.19-1.89) and NR (HR=4.53; 95% C.I. = 1.86-11.03) found to be independent prognostic factors of survival.

CONCLUSION

Prognostic significance of N status and NR status was comparable. Unlike N status, NR is independent by the number of resected nodes, and therefore it is particularly useful in case of conventional lymphadenectomy.