Prognostic value of the nodal ratio in gastric cancer: Unicentric analysis pf 199 patients.

Introduction: In the gastric cancer the most widely used classification is the AJCC TNM system. However, it presents limitations, such as staging migration in cases with suboptimal lymphadenectomies. The nodal ratio has been proposed as an alternative system, proving to be a good prognostic predictor of survival. The aim was to assess the influence of the nodal ratio measured in tertiles [tNR] as a prognostic factor and compare with the TNM systems (7th ed.) and log odds of positive lymph nodes [LODDS].

Material And Methods: Retrospective and single-center study on 199 patients operated on with curative intent between 2010 and 2014. For each system an univariate and multivariate analysis was performed and the overall survival rates [OS] were compared by the ROC test.

Results: The prognostic factors that showed statistical significance in the multivariate analysis were: tNR2 (HR 2.87) and tNR 3 (HR 7.29); LODDS 2 (HR 1.55), LODDS3 (HR 2.6) and LODDS4 (HR 4.9); pN2 (HR 1.84) and pN3 (HR 2.91). The 5-year OS was 75.8, 61.4, 25.8 and 3.84% for tNR0, tNR1, tNR2 and tNR3; 72.4, 60, 29.1 and 13.9% for LODDS1, LODDS2, LODDS3 and LODDS4; and 77.6, 59.4, 28.8 and 25.5% for pN0, pN1, pN2 and pN3, respectively. The three systems behaved as good predictors, with areas under the curve >0.75.

Conclusion: tNR was an independent prognostic factor for estimating survival in gastric cancer. Furthermore, the ease of its calculation in clinical practice could reduce the effect of staging migration.