Prognostic value of the IASLC completeness-of-resection classification after neoadjuvant therapy for non-small cell lung cancer.

Abstract

Objectives: The prognostic significance of the International Association for the Study of Lung Cancer (IASLC) completeness-of-resection classification after neoadjuvant therapy for non-small cell lung cancer (NSCLC) remains poorly defined, particularly in the chemoimmunotherapy era. We evaluated its prognostic value in a contemporary real-world cohort.

Methods: This retrospective single-centre study included consecutive patients undergoing pulmonary resection after neoadjuvant therapy for NSCLC between January 2017 and June 2026. Resections were retrospectively classified according to IASLC criteria as complete, uncertain, or incomplete. The primary endpoint was progression free survival (PFS) and the secondary endpoint was overall survival (OS). Survival was assessed using Kaplan-Meier and multivariable Cox regression analyses.

Results: Among 98 patients, 45 (45.9%) had complete, 44 (44.9%) uncertain, and 9 (9.2%) incomplete resection; 51% received neoadjuvant chemoimmunotherapy. After a median follow-up of 20.5 months, PFS decreased stepwise from complete to uncertain and incomplete resection (log-rank p = 0.07). After adjustment, incomplete resection was associated with an approximately threefold higher hazard of progression or death compared with complete resection, although statistical significance was not reached (HR 2.82, 95% CI 0.94-8.43; p = 0.064). Uncertain resection was not associated with PFS, and completeness-of-resection status was not independently associated with OS.

Conclusions: IASLC completeness-of-resection status showed a clinically relevant PFS gradient after neoadjuvant therapy, with the poorest outcomes after incomplete resection. Although the adjusted association did not reach statistical significance, these findings support the clinical relevance and standardized reporting of the IASLC framework as a measure of oncological surgical quality in contemporary multimodal practice, including among patients receiving neoadjuvant chemoimmunotherapy.