Prognostic impact of lymph node spreading pattern in N2 NSCLC patients

Area of Science:

• Thoracic Oncology
• Surgical Oncology
• Cancer Research

Background:

• Locally advanced non-small cell lung cancer (NSCLC) accounts for one-third of diagnoses.
• Poor long-term survival in stage IIIA/B-N2 NSCLC may be linked to lymph node metastasis patterns.
• Understanding lymph node involvement is crucial for predicting outcomes in advanced NSCLC.

Purpose of the Study:

• To compare the overall survival rates of stage IIIA/B-N2 NSCLC patients based on lymph node involvement.
• To investigate survival differences between patients with superior mediastinal lymph nodes (SML) versus infracarinal/inferior mediastinal lymph nodes (IML) and multilevel disease (MLD).
• To identify prognostic factors influencing survival in surgically treated stage IIIA/B-N2 NSCLC.

Main Methods:

• Retrospective review of 129 stage IIIA/B-N2 NSCLC patients who underwent surgery between 2012 and 2020.
• Comparison of survival rates (1-, 3-, and 5-year) among patients with SML (n=62), IML (n=37), and MLD (n=30).
• Statistical analysis using Kaplan-Meier curves and Cox proportional hazards models to assess survival and prognostic factors.

Main Results:

• Patients with SML demonstrated significantly higher 1-year (95.2%), 3-year (78.8%), and 5-year (61.1%) survival rates compared to IML and MLD groups.
• Kaplan-Meier analysis revealed significantly prolonged overall survival for the SML group (p < 0.0001).
• In contrast, IML and MLD patient groups exhibited poor survival rates across all measured time points (p < 0.001).

Conclusions:

• Superior mediastinal lymph node involvement in stage IIIA/B-N2 NSCLC is associated with significantly better long-term survival.
• Infracarinal/inferior mediastinal lymph node involvement and multilevel disease portend a poor prognosis in this patient cohort.
• Lymph node spreading pattern is a critical prognostic indicator for surgically treated stage IIIA/B-N2 NSCLC patients.