Segmentectomy for Inner Location Small-Sized Non-Small Cell Lung Cancer: Is It Feasible?

The efficacy of segmentectomy for inner small-sized non-small-cell lung cancer (NSCLC) remains unknown. We aimed to elucidate whether segmentectomy for inner small-sized NSCLC, defined using a novel 3-dimensional measuring method, yields feasible oncologic outcomes compared with segmentectomy for outer lesions.

We retrospectively analyzed patients with small-sized (<2 cm) cN0 NSCLC who underwent segmentectomy between January 2007 and December 2020. The tumor centrality ratio, which was measured by using 3-dimensional reconstruction software, was evaluated. The location of tumor origin was confirmed pathologically. Cases with a ratio <2:3 and >2:3 were allocated to the inner group and outer group, respectively. Oncologic outcomes were compared between the 2 groups.

Our cohort was divided into the inner group (n = 75) and outer group (n = 127). The proximal distance from a tumor was >20 mm in all cases. The tumor centrality ratio was associated with the pathologic origin of a tumor. The rate of unforeseen positive lymph node metastasis was significantly higher in the inner group (P = .04). There were no significant differences in the 5-year recurrence-free survival (91% vs 87%, P = .67). Univariate analysis identified age, consolidation/tumor ratio, the presence of ground-glass opacity, and lymphovascular invasion, but not tumor centrality, as significant prognostic factors for recurrence-free survival. In the multivariate analysis, the presence of ground-glass opacity and lymphovascular invasion remained significant.

Regarding oncologic outcomes, segmentectomy with a safety proximal distance could be feasible, even for inner small-sized NSCLC. Tumor invasiveness, not tumor centrality, may influence tumor recurrence.