Lobar versus Sub-Lobar Resection for Clinical Stage IA1-2 Non-Small Cell Lung Cancer with Tumor Spread Through Air Spaces.

Background: Controversy persists regarding the efficacy of sub-lobar resection(SR) versus lobar resection(LR) for clinical IA non-small cell lung cancer with tumor spread through air spaces, suggesting that a one-size-fits-all approach may be inappropriate for this heterogeneous population. This study aims to identify the factors potentially modifying the survival benefits of LR over SR in clinical IA spread through air spaces-positive non-small cell lung cancer.

Methods: Consecutive peripheral clinical IA1-2 spread through air spaces-positive non-small cell lung cancer patients undergoing surgery between 2014 and 2020 at 6 high-volume institutions were retrospectively reviewed. Propensity-score matching was used to mitigate selection bias. The primary endpoint was recurrence-free survival.

Results: Among 4555 cases, propensity-score matching resulted in 1238 and 2476 patients in SR and LR groups, respectively, who were used for further investigation. LR yielded better prognoses compared to SR in the overall cohort. Interaction and stratified analyses further revealed that LR significantly improved survival compared to SR in clinical IA2 patients, whereas survival outcomes were comparable between two approaches in clinical IA1 patients. In lymphovascular invasion-negative pathological IA subcohorts, adjuvant therapy improved survival in pathological IA2-3 patients receiving SR, but showed no survival benefit in pathological IA1 patients, or pathological IA2-3 patients undergoing LR.

Conclusions: Collectively, clinical IA2 patients may derive greater benefit from LR, while clinical IA1 patients could be considered appropriate candidates for SR. In lymphovascular invasion-negative pathological IA subcohorts, adjuvant therapy could be recommended for pathological IA2-3 patients after SR, while it may not be necessary for those receiving LR or pathological IA1 patients.