Segmentectomy for non-peripheral and peripheral small-sized non-small-cell lung cancer.

Objectives: To compare the oncological outcomes of segmentectomy for non-peripheral versus peripheral small-sized non-small-cell lung cancer (NSCLC).

Methods: This retrospective observational study included patients with clinical stage IA1-A2 NSCLC who underwent segmentectomy. Patients were separated based on tumour distance index (DI, which was calculated as the ratio of the distance from the entrance of the segmental bronchus to the proximal tumour margin to the distance to the lobar pleura along the same line): non-peripheral group (DI ≤ 2/3) and peripheral group (DI > 2/3). Disease-free survival (DFS) and overall survival were compared with log-rank tests.

Results: 850 patients were included, comprising 274 in the non-peripheral group and 576 in the peripheral group. Recurrence occurred in 68 patients (24 in the peripheral group and 44 in the non-peripheral group), and 56 patients died (22 in the peripheral group and 34 in the non-peripheral group). Log-rank tests showed no statistical differences in 5-year DFS (92.2% vs 91.2%) and 5-year overall survival (96.3% vs 93.6%) between the two groups, but higher margin recurrence occurred in the non-peripheral group. Multivariable analysis revealed that age, tumour diameter, consolidation-to-tumour ratios, pathological subtype and pathologic stage were independent risk factors for DFS. Subgroup analysis indicated that patients with a non-peripheral solid NSCLC had a worse 5-year DFS (62.1% vs 76.3%) and a higher margin recurrence rate (13.2% vs 2.0%).

Conclusions: Segmentectomy for small-sized non-peripheral NSCLC could gain a comparable outcome to the peripheral, but worse DFS and higher margin recurrence occurred in the non-peripheral solid NSCLC.