Survival outcomes with the use of immunotherapy (IO) in patients (pts) with metastatic non-small cell lung cancer (mNSCLC) at a large hybrid cancer institute.

Abstract

e21192 Background: Landmark trials have shown increased survival in pts who receive IO for NSCLC as compared to chemotherapy (chemo). Median overall survival (mOS) ranged from 17-26 months (mo); however, mOS in several published “real-world” retrospective studies are lower, ranging from 8-12 mo, with about 4-5 months on IO treatment. We sought to define mOS of pts with mNSCLC who received IO as monotherapy or in combination with chemo as first line therapy at Levine Cancer Institute. Methods: We retrospectively reviewed 315 adult pts with mNSCLC without driver mutations diagnosed between 2016 and 2019. The Kaplan-Meier method was used to estimate and compare OS between IO and IO + chemo. Univariate and multivariate Cox models were used to evaluate risk factors (RF) for OS. RFs considered included age, sex, race, smoking status, histology, first-line treatment type, and metastatic (mets) sites. Results: Baseline pt characteristics were: 40% female, 77% white, 20% Black, 34% current smokers and 60% former smokers. Median age was 69 years (45-88) in pts receiving IO alone and 63 years (28-84) in pts receiving IO + chemo. Tumor characteristics were: 76% adenocarcinoma and 17% squamous cell carcinoma. PD-L1 TPS distribution was: 39% for 0%, 22% for 1-49%, and 39% for ≥50%. Distribution of mets was 10% adrenal, 40% bone, 30% brain, 14% liver, 31% lung. mOS for pts receiving IO and IO + chemo as first line therapy was 17 and 14.8 mos, respectively (P = .209). Median duration of IO received was 4.25 months (0 to 43.6). mOS as stratified by PD-L1 TPS was 14.5 mos for PD-L1 0%, 13.3 mos for PD-L1 1-49%, and 19.5 mos for PD-L1 ≥50% (P = .163). OS was significantly different between IO and IO + chemo after adjusting for age. No OS differences were seen between white and Black or between all pts vs pts with brain mets (brain-specific interventions not reviewed). The table summarizes significant findings only (P < 0.05). Conclusions: Pts with mNSCLC treated first-line with IO either alone or with chemo at Levine Cancer Institute lived longer than those in similar published “real-world” cohorts. Median OS was highest in patients with PD-L1 TPS ≥50%, although not statistically significant. While not unusual to identify worse outcomes in those with bone and liver mets, interestingly brain metastasis was not associated with worse survival. In this cohort, when adjusted for age, IO alone trends toward improved survival. Although there was no OS difference based on race, further investigation will seek to uncover any other disparities contributing to outcomes, such as insurance status and zip code mapping. To our knowledge, this provides the largest analysis of this patient population outside of a clinical trial.[Table: see text]