A modified subclassification to evaluate the survival of patients with N3 gastric cancer: an international database study

Treatment Outcomes and Prognostic Factors in N3 Stage Gastric Cancer After Curative Resection: A Real World Data

Purpose

N3 gastric cancer is characterized by a fairly high lymph node metastasis burden and poor outcome despite optimal therapy. Given the limitations of TNM classification, a comprehensive evaluation tool is necessary to predict the prognosis of patients with N3 gastric cancer who underwent curative surgery. This study aims to explore the outcomes and clinicopathologic prognostic factors affecting the overall survival (OS) of patients with N3 gastric cancer after surgery.

Methods

Data on patients with N3 gastric cancer who underwent (sub)total gastrectomy and regional lymph node dissection between November 2005 and September 2018 (n = 169) were analyzed by Cox regression to determine the independent prognostic factors for OS.

Results

The multivariable analysis established that gender, patient performance status, metastatic lymph node ratio (MLNR), tumor grade, and adjuvant chemotherapy are significantly associated with OS. The five-year OS of the study population was 15%. Adjuvant chemoradiotherapy was applied to 72% of the patients, which resulted in an improvement in recurrence-free survival but not OS. Recurrence occurred in 103 (75%) patients, in which the most frequent recurrence site was distant metastasis.

Conclusion

Male gender, poor performance status, grade 3 tumor, MLNR > 0.37, and not receiving adjuvant chemotherapy are predictors of poor prognosis in N3 gastric cancer after curative resection. Considering the high recurrence rates of this group, prospective studies are needed to optimize treatment strategies.

Development of a simplified tumor-lymph node ratio classification system for patients with resected gastric cancer: A western study

INTRODUCTION

Gastric cancer (GC) shows high recurrence and mortality rates. The AJCC TNM staging system is the best prognostic predictor, but lymph node assessment is a major source of controversy. Recent studies have found that lymph node ratio (LNR) may overcome TNM limitations. Our aim is to develop a simplified tumor-LNR (T-LNR) classification for predicting prognosis of resected GC.

METHODS

Retrospective study of all GC resected in a tertiary center in Spain (N = 377). Clinicopathological features were assessed, LNR was classified into N0:0%, N1:1-25%, N2:>25%, and a T-LNR classification was developed. Statistical analyses were performed.

RESULTS

317 patients were finally included. Most patients were male (54.6%) and mean age was 72 years. Tumors were intestinal (61%), diffuse (30.8%) or mixed (8.1%). During follow-up, 36.7% and 27.4% of patients progressed and died, respectively. T-LNR classification divided patients into five prognostic categories (S1-S5). Most cases were S1-S4 (26.2%, 19.9%, 22.6% and 23.6%, respectively). 7.6% of tumors were S5. T-LNR classification was significantly associated with tumor size, depth, macroscopical type, Laurén subtype, signet ring cells, histologic grade, lymphovascular invasion, perineural infiltration, infiltrative growth, patient progression and death. Kaplan-Meier curves for OS showed an excellent patient stratification with evenly spaced curves. As for DFS, T-LNR classification also showed good discriminatory ability with non-overlapping curves. T-LNR classification was independently related to both OS and DFS.

CONCLUSIONS

T-LNR classifications can successfully predict prognosis of GC patients. Larger studies in other geographic regions should be performed to refine this classification and to validate its prognostic relevance.