Comparison of recurrence risk between patients with clinically node-positive and -negative stage I non-small cell lung cancer following surgery: A propensity score matching analysis.

Background: Identifying patients with stage I non-small cell lung cancer (NSCLC) at increased risk of tumor recurrence following surgery remains a major challenge. The current study aimed to compare disease-free survival (DFS) rates after surgery between patients with clinically node-positive (cN+) and -negative (cN0) stage I NSCLC.

Methods: Patients with pathological stage I resected NSCLC were identified from the lung cancer database of Changhua Christian Hospital in Taiwan. Patients with clinical N status 1 or 2 and pathological N status 0 were identified as the cN+/pN0 cohort, whereas others were identified as the cN0/pN0 cohort. Propensity score matching (PSM) was used to balance the baseline characteristics between both cohorts. Kaplan-Meier method and Cox proportional hazards model were used to evaluate DFS.

Results: From January 2010 to July 2019, 754 eligible patients were enrolled into the study, among whom 41 (5.4%) were cN+/pN0. The median follow-up time was 43.4 months. Before PSM, the 5-year DFS rate was 79.0% and 90.3% in cN+/pN0 and cN0/pN0 cohorts (log-rank test, p = 0.009), respectively. After a 1:4 PSM, multivariate analysis showed that the cN+/pN0 cohort still had a poorer DFS compared to the cN0/pN0 cohort in (hazard ratio, 3.17; p = 0.040).

Conclusion: Among patients with stage I resected NSCLC, cN+ patients had a worse DFS compared to cN0 patients. Surgeons should therefore consider more aggressive adjuvant therapy or frequent follow-up in patients with surgically resected stage I NSCLC with cN+ status.