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

• Published in: Annals of diagnostic pathology 2021-02, Vol.50, p.151677-151677, Article 151677
• Main Authors: Díaz del Arco, Cristina, Estrada Muñoz, Lourdes, Sánchez Pernaute, Andrés, Ortega Medina, Luis, García Gómez de las Heras, Soledad, García Martínez, Ricardo, Fernández Aceñero, Mª. Jesús
• Format: Article
• Language: English
• Subjects: Gastric cancer; Lymph node ratio; Prognosis; T-LNR; TNM classification
• ISSN: 1092-9134; 1532-8198
• DOI: 10.1016/j.anndiagpath.2020.151677

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. 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. 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. 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. •Lymph node assessment in resected gastric cancer is a major source of controversy.•Lymph node ratio may be helpful to overcome TNM staging limitations.•Our T-LNR classification divided patients into five prognostic categories.•T-LNR staging was an independent prognostic factor for both OS and DFS.•T-LNR showed an excellent discriminatory ability in patients with gastric cancer.