Could less be enough: sublobar resection vs lobectomy for clinical stage IA non-small cell lung cancer patients with visceral pleural invasion or spread through air spaces.

Background: While recent randomized controlled trials have demonstrated that sublobar resection (SLR) is non-inferior to lobectomy, the comparative efficacy of these procedures remains uncertain for early-stage non-small cell lung cancer (NSCLC; ≤3 cm) exhibiting invasive features postoperatively, such as visceral pleural invasion (VPI) or spread through air spaces (STAS).

Materials and methods: To identify eligible studies, a comprehensive search of PubMed, Embase, MEDLINE, the Cochrane Library, and Web of Science was conducted through 25 July 2024. Studies were screened according to predefined criteria in accordance with PRISMA guidelines. The primary endpoints were 5-year overall survival (OS) and recurrence-free survival (RFS). Hazard ratios (HR) and 95% confidence intervals (CI) were used to perform a meta-analysis.

Results: The final analysis included 14 retrospective studies and 1 randomized controlled trial, encompassing a total of 8054 patients with NSCLC (tumors ≤3 cm) exhibiting VPI or STAS. The meta-analysis revealed that SLR was associated with impaired 5-year OS (HR: 1.25; 95% CI: 1.10-1.41) and slightly inferior RFS (HR: 1.25; 95% CI: 0.99-1.58) compared to lobectomy for pT2a (VPI) NSCLC patients with tumor ≤3 cm. Similarly, SLR was associated with significantly worse 5-year OS (HR: 2.58; 95% CI: 1.92-3.45) and 5-year RFS (HR: 2.42; 95% CI: 1.69-3.46) compared to lobectomy for stage IA NSCLC patients with STAS. Subgroup analysis revealed that statistically significant differences in 5-year OS (HR: 1.13; 95% CI: 0.92-1.38) and 5-year RFS (HR: 0.87; 95% CI: 0.56-1.36) were not observed between the SLR and lobectomy groups for pT2a (VPI) NSCLC patients with tumor ≤2 cm. Additionally, no statistically significant survival difference was observed between the segmentectomy and lobectomy groups for NSCLC patients (≤3 cm) with VPI (5-year OS: HR: 1.16; 95% CI: 0.89-1.52; 5-year RFS: HR: 1.07; 95% CI: 0.88-1.30) or STAS (5-year OS: HR: 3.88; 95% CI: 0.82-18.31; 5-year RFS: HR: 1.64; 95% CI: 0.70-3.80).

Conclusions: For early-stage (≤3 cm) NSCLC with VPI or STAS, SLR was associated with worse survival outcomes compared to lobectomy. However, segmentectomy achieved survival outcomes comparable to those of lobectomy. For pT2a (VPI) NSCLC patients with tumor ≤2 cm, the differences in survival outcomes between SLR and lobectomy were not statistically significant.