Abstract 5962: Real-world practice patterns and outcomes after platinum and immunotherapy in stage III vs IV non-small cell lung cancer (NSCLC)
Authors: Kundu Palak , Gondos Adam , Tanaka Tomohiro , Chun Elaine , Ballinger Marcus 
Published: June 2022

Abstract
Background: Treatment of patients with locally advanced lung cancer includes platinum-based chemoradiation followed by anti-PD-L1/PD-1 immunotherapy. Over half of patients receiving this treatment have disease progression and may be re-challenged with further platinum or immunotherapy, or instead be treated with an approved third line (3L) therapy similar to that for patients initially diagnosed with stage IV disease that progressed on platinum and immunotherapy. It is unknown whether treatment outcomes and prognosis in the stage III setting, particularly in patients with early disease progression, mirror the stage IV setting. The purpose of this study was to evaluate current real-world practice patterns and survival for patients with stage III vs IV disease previously treated with platinum and immunotherapy.
Methods: The Flatiron NSCLC database was used to identify patients whose disease progressed after platinum chemotherapy and anti-PD-L1/PD-1 therapy, and to further classify them as 1) stage III early progressors (≤ 6 months) after sequential platinum and durvalumab, 2) stage III late progressors (&gt; 6 months) after sequential platinum and durvalumab, and 3) stage IV progressors after concurrent or sequential platinum and anti-PD-L1/PD-1 therapy. The proportion of stage III patients receiving additional platinum or immunotherapy vs approved 3L therapy (docetaxel ± ramucirumab, pemetrexed, or gemcitabine) was then evaluated. A Cox proportional hazards model was used to compare median overall survival in the stage III groups and the stage IV group starting the next line of treatment after initial platinum and immunotherapy, and adjusting for ECOG performance status, smoking history, histology, PD-L1 status, age, sex, and race.
Results: Patients identified as receiving their first-line therapy between December 2017 and November 2020 included 143 stage III early progressors, 120 stage III late progressors and 876 stage IV patients. After initial platinum and immunotherapy, 34% of stage III early progressors received platinum or immunotherapy and 12% received approved 3L therapy. 39% of stage III late progressors received platinum or immunotherapy and 15% received approved 3L therapy. Median overall survival for early vs late stage III progressors did not significantly differ (10.1 vs 14.3 months; HR 0.89; 95% CI: 0.53, 1.51; P=0.67). Survival in stage III patients was longer than that in stage IV patients (median 6.2 months) among both early progressors (HR, 0.60; 95% CI: 0.44, 0.82; P=0.002) and late progressors (HR, 0.51; 95% CI: 0.51, 0.34; P=0.001).
Conclusions: Patients with stage III NSCLC that progressed on initial platinum and immunotherapy were more likely to be re-challenged with platinum or immunotherapy than to immediately proceed to 3L therapy. These patients also had longer survival than analogous stage IV patients, regardless of progression timing.
Citation Format: Palak Kundu, Adam Gondos, Tomohiro Tanaka, Elaine Chun, Marcus Ballinger. Real-world practice patterns and outcomes after platinum and immunotherapy in stage III vs IV non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5962.