Lobar vs Sublobar Resection for Clinical Stage IA1-2 Non-Small Cell Lung Cancer With Tumor Spread Through Air Spaces.

[BACKGROUND] Controversy persists regarding the efficacy of sublobar resection (SR) vs lobar resection (LR) for clinical stage IA non-small cell lung cancer with tumor spread through air spaces, thus suggesting that a 1-size-fits-all approach may be inappropriate for this heterogeneous population. This study aimed to identify the factors potentially modifying the survival benefits of LR over SR in clinical stage IA spread through air spaces-positive non-small cell lung cancer.

[METHODS] The study retrospectively reviewed consecutive peripheral clinical stage IA1 to IA2 spread of air spaces-positive non-small cell lung cancer in patients who underwent surgery between 2014 and 2020 at 6 high-volume institutions. Propensity score matching was used to mitigate selection bias. The primary end point was recurrence-free survival.

[RESULTS] Among 4555 cases, propensity score matching resulted in 1238 and 2476 patients in the SR and LR groups, respectively, who were included for further investigation. LR yielded better prognoses compared with SR in the overall cohort. Interaction and stratified analyses further revealed that LR significantly improved survival compared with SR in patients with clinical stage IA2, whereas survival outcomes were comparable between the 2 approaches in patients with clinical stage IA1 disease. In lymphovascular invasion-negative pathologic stage IA subcohorts, adjuvant therapy improved survival in pathologic stage IA2 to IA3 patients undergoing SR, but it showed no survival benefit in patients with pathologic stage IA1 disease or in patients with pathologic stage IA2 to 1A3 who underwent LR.

[CONCLUSIONS] Collectively, patients with clinical stage IA2 disease may derive greater benefit from LR, whereas patients with clinical stage IA1 disease could be considered appropriate candidates for SR. In cohorts with lymphovascular invasion-negative pathologic stage IA disease, adjuvant therapy could be recommended for patients with pathologic IA2 to IA3 after SR, whereas it may not be necessary for patients undergoing LR or for patients with pathologic stage IA1 disease.