Prognostic Impact of Visceral Pleural Invasion in Node-Negative Non-Small Cell Lung Cancer with Tumors ≤ 3 cm

Background and Objectives: Visceral pleural invasion (VPI) up-classifies non-small cell lung cancer (NSCLC) tumors measuring ≤3 cm from T1 to T2; however, whether this stage migration translates into worse survival in pathologically node-negative disease remains uncertain. This study evaluated the prognostic impact of VPI on overall survival (OS) and progression-free survival (PFS) in this selected population. Materials and Methods: This retrospective single-center cohort study included patients who underwent surgical resection for pathologically node-negative NSCLC with tumors ≤ 3 cm between 2015 and 2021. In the primary analysis, patients with PL0 were compared with those with PL1-PL2, whereas PL3 cases were excluded from the primary comparison and evaluated only in exploratory analyses. Survival outcomes were assessed using Kaplan-Meier analysis and univariable and multivariable Cox regression models. Results: A total of 241 patients were included in the overall cohort (PL0, n = 179; PL1, n = 48; PL2, n = 9; PL3, n = 5). After exclusion of PL3 from the primary analysis, 236 patients remained, including 179 with PL0 and 57 with PL1-PL2. During follow-up, 58 deaths and 81 PFS events occurred in the primary analytic cohort. Kaplan-Meier analysis showed no significant differences between PL0 and PL1-PL2 in OS (log-rank p = 0.655) or PFS (log-rank p = 0.904). In multivariable analysis, VPI was not independently associated with OS (HR 0.785, 95% CI 0.389-1.582; p = 0.498) or PFS (HR 0.908, 95% CI 0.507-1.624; p = 0.744). Increasing age was independently associated with worse OS and PFS, whereas male sex and pneumonectomy were independently associated with worse OS. Conclusions: In surgically treated patients with pathologically node-negative NSCLC and tumors ≤ 3 cm, VPI defined as PL1-PL2 was not independently associated with OS or PFS. These findings suggest that the prognostic implications of VPI-driven up-classification may be context-dependent and should be interpreted together with other clinicopathological factors.