# Prognostic value of lymph node staging systems in gastric cancer patients undergoing laparoscopic surgery: A case-series in Vietnam

## TL;DR

This study compares different lymph node staging systems in gastric cancer patients in Vietnam to determine which best predicts survival outcomes.

## Contribution

This is the first study in Vietnam to evaluate LNR and LODDS as complementary tools for gastric cancer staging.

## Key findings

- LNR and LODDS showed better prognostic accuracy than pN in predicting survival outcomes.
- LODDS differentiated survival outcomes better than LNR in patients without lymph node metastasis (pN0).
- LNR retained prognostic significance in patients with fewer than 15 lymph nodes dissected.

## Abstract

Lymph node metastasis is the most important prognostic factor for gastric cancer (GC). While the pN staging system is widely used, it does not account for the total number of dissected lymph nodes, potentially leading to stage migration in patients with suboptimal lymphadenectomy. Alternative systems such as the lymph node ratio (LNR) and log odds of positive nodes (LODDS) may provide superior prognostic accuracy. Our aim is to compare the prognostic significance of the lymph node ratio (LNR), log odds of positive nodes (LODDS), and number of positive lymph nodes (pN).

Eighty-six GC patients treated with curative laparoscopic surgery were retrospectively analyzed. Survival outcomes were assessed using Kaplan-Meier analysis and the log-rank test. Prognostic accuracy was evaluated using receiver operating characteristic (ROC) curves and the area under the curve (AUC) values.

All three lymph node classification systems, pN, LNR, and LODDS, were significant prognostic factors for survival in gastric cancer, (p = 0.007, 0.002, and 0.036, respectively) based on the log-rank test. Notably, in cases with fewer than 15 lymph nodes dissected, only the LNR system retained prognostic significance (p = 0.037), whereas both LNR and LODDS were effective in the ≥15 lymph node subgroup.

LNR and LODDS can be recommended for evaluating lymph node metastasis in gastric cancer, particularly in patients with inadequate lymph node dissection. This is the first study in Vietnam to evaluate and support the integration of LNR and LODDS as complementary prognostic tools in gastric cancer staging.

•LNR (AUC = 0.685) and LODDS (AUC = 0.683) demonstrated better prognostic accuracy than pN (AUC = 0.677).•LODDS may differentiate survival outcomes better than LNR in patients without lymph node metastasis (pN0).

LNR (AUC = 0.685) and LODDS (AUC = 0.683) demonstrated better prognostic accuracy than pN (AUC = 0.677).

LODDS may differentiate survival outcomes better than LNR in patients without lymph node metastasis (pN0).