Lymph nodes metastatic burden as a prognosticator for advanced non-small cell lung cancer: a real-world study.

BACKGROUND

Current nodal classification inadequately predicts outcomes for advanced non-small cell lung cancer (NSCLC) patients. We investigated whether metastatic lymph node characteristics could improve prognostic accuracy.

METHODS

We retrospectively analyzed 339 patients with advanced NSCLC who received immunotherapy as first-line treatment. Lymph node imaging was performed using computed tomography (CT), and the X-tile software was employed to determine optimal cutoff values for lymph node size and number. Prognostic factors were assessed using Kaplan-Meier survival curves and multivariate Cox regression analysis. The predictive accuracy of various N-staging was evaluated through time-dependent receiver operating characteristic (ROC) curves.

RESULTS

The optimal cutoff values for lymph node size and number were 1.60 cm and 3, respectively. Kaplan-Meier analysis indicated that size, number, and fusion of metastatic lymph nodes were associated with worse overall survival (OS) in advanced NSCLC patients {hazard ratio (HR) [95% confidence interval (CI)]: 2.179 (1.432-3.316), 1.859 (1.226-2.821), and 3.635 (1.796-7.358)}. Multivariate Cox regression analysis identified lymph node size [HR (95% CI): 6.21 (1.19-32.25)] and fusion [HR (95% CI): 3.20 (1.32-7.75)] as independent prognostic factors for OS. Incorporating lymph node size into the conventional N-staging system improved prognostic accuracy, with a 3-year area under the curve (AUC) of 0.651 (95% CI: 0.535-0.767).

CONCLUSIONS

Lymph node size serves as a valuable indicator of tumor invasion and can enhance the existing N-staging system for more accurate prognosis prediction for more accurate prognosis prediction in advanced NSCLC.