Modified American Joint Committee on Cancer Tumor-Node-Metastasis Staging System Based on the Node Ratio Can Further Improve the Capacity of Prognosis Assessment for Gastric Cancer Patients

Prognostic value of lymph node density on cancer staging system for gastric cancer without distal metastasis: a population-based analysis of SEER database

Background

Accurate tumor staging is the cornerstone of tumor treatment. Current tumor staging system for gastric cancer (GC) is based on regional positive lymph nodes while ignoring the total number of examined lymph nodes. We aim to assess the prognostic value of lymph node density (LND), the ratio of positive nodes to the total number examined nodes, in GC without distal metastasis.

Methods

Clinical information of patients with histologically confirmed GC and without distal metastasis was identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. The X-Tile software was used to identify the ideal prognosis-related cutoff point for LND. The prognostic value of LND on cancer-specific survival (CSS) and overall survival (OS) was assessed in Cox regression models. Subgroup analysis stratified by LND was performed on current lymph node staging system to further explore the interaction between LND and current lymph node staging system.

Results

A total of 4281 participants were identified from the SEER database for the final analysis. The optimal prognosis-related cutoff values of LND were calculated as 0.1 and 0.4, and LND was divided into three levels: LND1 (< 0.1), LND2 (> = 0.1, < 0.4), and LND3 (> = 0.4). LND3 was associated with worse CSS and OS in GC patients. Compared to patients with LND1, those with LND2 and LND3 had 2.43 (HR = 2.43, 95% CI 2.09–2.84, P < 0.001) and 4.69 (HR = 4.69, 95% CI 4.02–5.48, P < 0.001) folds increase in mortality in CSS, respectively. Similar results were found in the evaluation of OS in GC patients. Subgroup analysis stratified by LND also found that patients in the same current lymph node stage still had different prognosis due to the different LND levels after adjustment for other prognosis-related covariates (all P values < 0.001).

Conclusion

LND is an independent prognostic factor for GC without distal metastasis. In the current lymph node staging system, LND has potential value in further accurately classifying GC patients without distal metastasis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02795-9.

Revisiting the 8th AJCC system for gastric cancer: A review on validations, nomograms, lymph nodes impact, and proposed modifications

Gastric cancer is the fifth most frequently diagnosed cancer worldwide, behind breast, lung, colorectal, and prostate cancers. In gastric cancer, multimodality treatment shows prospective benefits and also improves survival. Surgery, however, is the mainstay of curative treatment. The staging of gastric cancer patients is critical for harmonization of care. Accurate stages assure that informed clinical decisions are timely made. The American Joint Committee on Cancer (AJCC) staging system is the most widely applied system in to determine the disease's prognosis and survival prediction. The recently adopted 8th AJCC TNM staging system has been revised to enhance its survival predictive power. Subsequent studies have established the validity of the current edition, demonstrating improved stage stratification, discriminatory power, and survival prediction. However, other studies have cast doubt on the superiority of the new edition. Innovations aimed at further improving its prognosis have resulted in developing of novel models. Advances in our understanding of the tumor microenvironment and molecular categorization of cancer have resulted in proposals for their inclusion in TNM staging as potential complementary factors that enhance survival prediction and prognostic assessment ability. The purpose of this study is to conduct a review of the published literature regarding the validity of the 8th AJCC TNM staging system, proposed modifications, and nomograms.

•

The 8th AJCC is valid in prognostic stratification of gastric cancer, however, revisions are still required.

•

The yPT staging requires some modifications and inclusion of stages that currently don't exist in the 8th AJCC.

•

High lymph nodes count and anatomical localization improve the prediction ability of the current AJCC.

•

Nomograms comprising of individual prognostic factors are crucial to the current AJCC.

•

Molecular markers positively influence survival prediction of gastric cancer.

Accurate Risk Stratification of Patients with Node-Positive Gastric Cancer by Lymph Node Ratio

BACKGROUND

We aimed to clarify the utility of lymph node ratio (LNR) for assessing the prognosis of patients with node-positive gastric cancer after curative gastrectomy.

METHODS

We retrospectively analyzed data of 973 patients with node-positive gastric cancer who had undergone curative gastrectomy at nine institutions from 2010 to 2014. Survival analysis was performed by comparing LNR low and high groups according to the optimal cutoff value of LNR, which was determined using receiver operating characteristic curve analysis.

RESULTS

LNR high was significantly associated with shorter disease-free survival and was an independent predictor of recurrence in all patients. Moreover, we obtained the similar results from analysis of each N stage. The prevalence of lymph node and peritoneal recurrence appeared to be higher in the LNR high group. Correlation analysis showed that LNR was negatively correlated with the number of retrieved nodes within every N stage; however, disease-free survival did not differ significantly between LNR low and high groups of each N stage with 16-30, 31-40, or >40 retrieved nodes.

CONCLUSIONS

LNR is a strong prognostic factor and predictor of recurrence in patients with node-positive gastric cancer who have undergone curative gastrectomy. The combination of LNR and N staging permits more accurate prognostic stratification of patients with gastric cancer and may contribute to developing novel prognostic models.