Impact of time to neoadjuvant treatment initiation (TTI) for resectable non-small cell lung cancer (NSCLC) on clinical outcomes.

Abstract

8069 Background: There has been significant progress in the management of resectable NSCLC, now utilizing biomarker selected criteria. However, in the era of these new perioperative treatments, the impact of treatment initiation and surgical timing on clinical outcomes have yet to be explored. Methods: Using the NCDB, we compiled an analytic data set of patients with stage IB-IIIB (per AJCC 8 th staging edition) who underwent definitive resection after receiving neoadjuvant systemic therapy between 2010-2021. These patients received neoadjuvant chemotherapy (CT), chemoradiotherapy (CRT) or chemoimmunotherapy (CIO). The following clinically relevant time intervals were estimated: time from diagnosis to systemic therapy initiation, from diagnosis to definitive surgery and from systemic therapy initiation to surgery. The association between these time intervals and overall survival (OS) were assessed using multivariable Cox proportional hazards model, stratified by clinical T-stage. Cox model was adjusted for year of diagnosis and age, treatment modalities, sex, race, Charlson score, income, and hospital affiliation. Data were analyzed using R studio and statistical significance was set at α = 0.05. Results: The analytic data set included 13,372 eligible patients. 40.5% of patients had stage I/II disease and 59.5% were diagnosed with stage III disease. Treatment included 45.2% CT, 48.3% CRT, 6.4% CIO, with median TTI being 108, 97 and 107 days, respectively. Compared to neoadjuvant CT, CIO combination conferred a positive impact on OS (HR=0.62, 95%CI: 0.52-0.74). Both time from diagnosis to treatment initiation and time from systemic therapy start to surgery increased by 7 days between 2010-2018 and 2019-2021. Time to neoadjuvant treatment initiation did not impact OS. However, surgical resection done later than 150 days from diagnosis was associated with lower OS (HR=1.12, 95%CI:1.04-1.19). Based on the multivariable Cox regression model, patients’ survival was longer if they were diagnosed between 2019-2021, treated at an academic hospital, age < 63 years at diagnosis, female, non-white, had lower Charlson score, income > 40K, private-payer insurance, and if surgical resection was performed ≤ 150 days from diagnosis. Conclusions: Exploring the NCDB, neoadjuvant CIO showed significantly favorable impact on OS compared to CT. Despite increased TTI between the years of 2019-2021, there was no appreciable impact on timing of systemic therapy initiation on OS across our cohort. Time to surgical resection within 150 days, adjusted for other clinical and demographic parameters, was associated with improved OS. Pertinent demographic variables, including race, insurance status, and income level, significantly impacted OS and warrant further investigation in this clinical setting.