Comparison of the Differences in Survival Rates between the 7th and 8th Editions of the AJCC TNM Staging System for Gastric Adenocarcinoma: a Single-Institution Study of 5,507 Patients in Korea

Abstract

PurposeThe aims of this study were to compare the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging manuals on tumor, node, and metastasis (TNM) staging systems and to evaluate whether the 8th edition represents a better refinement of the 7th staging system, when applied for the classification of gastric cancers.Materials and MethodsA total of 5,507 gastric cancer patients, who underwent treatment from January 1989 to December 2013 at a single institute, were included. We compared patient survival rates across the disease groups classified according to the 7th and 8th editions of the AJCC TNM staging systems.ResultsStage migration was observed in 6.4% (n=355) of the patients. Of these, 3.5% (n=192) and 2.9% (n=158) of patients showed a higher stage and lower stage, respectively. According to the 8th edition of the AJCC TNM staging criteria, the 5-year overall survival rates of the patients with stage IIIB and IIIC showed a significant difference (40.8% vs. 20.2%, P<0.001) whereas no significant differences in the 5-year overall survival rates were observed according to the 7th edition criteria (37.6% vs. 33.2%, P=0.381).ConclusionsRestaging stage III cancers according to the 8th edition of the AJCC TNM classification criteria improved survival rate discrimination, particularly, in institutes where the stage III patients were not distinctly categorized.

Superiority of the 8th edition of the TNM staging system for predicting overall survival in gastric cancer: Comparative analysis of the 7th and 8th editions in a monoinstitutional cohort

“…By subsequent analysis with survival curves and multivariable Cox proportional regression model, the 8th TNM was demonstrated to be superior to the 7th TNM in predictive capacity by distinctly discriminating survival time and rate in patients with stage IIIA from those in stage IIIB. Kim et al analyzed the stage distribution and migration for the AJCC 7th and 8th editions of the staging system based on a cohort of 5,507 patients from Korea (23).…”

Ratio‐based staging systems are better than the 7th and 8th editions of the TNM in stratifying the prognosis of gastric cancer patients: A multicenter retrospective study

“…Although the TNM 8th edition proved to be superior to the TNM 7th edition in predicting overall survival, [4][5][6][7] both editions are subject to the risk of stage migration. The phenomenon of stage migration occurs when the number of examined lymph nodes is insufficient.…”

“…For this reason, the prognostic accuracy of the node subsection (N) of the American Joint Committee on Cancer (AJCC) tumor‐node‐metastasis (TNM) classification has been pursued in all its late editions. Although the TNM 8th edition proved to be superior to the TNM 7th edition in predicting overall survival, both editions are subject to the risk of stage migration. The phenomenon of stage migration occurs when the number of examined lymph nodes is insufficient.…”

Clinical significance of conversion surgery for gastric cancer with peritoneal dissemination: A retrospective study

“…Gastric cancer is one of most common gastrointestinal malignancies in Asia and the third leading cause of cancer death worldwide [1]. Although recent developments in chemotherapy have considerably improved the prognosis of patients with unresectable advanced or recurrent gastric cancer, studies have reported a 8.8-14.9% 5-year survival rate among patients with stage IV disease [2,3]. In particular, peritoneal dissemination has been one of the representative metastatic patterns among patients with advanced gastric cancer, with large type-3 and type-4 tumors frequently leading to peritoneal dissemination (P1) or positive peritoneal cytology (CY1) [4].…”