Abstract
BACKGROUND: The benefits of continuing immunotherapy beyond disease progression in advanced non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) remain uncertain, along with the specific patient subgroups that may gain the most from this approach. This retrospective study aims to evaluate the efficacy of this approach and identify target patient populations likely to benefit. METHODS: We collected data from patients with NSCLC and SCLC who experienced disease progression following initial immune checkpoint inhibitor (ICI) treatment from January 2020 to December 2023. Patients were categorized based on second-line treatment: those receiving immunotherapy beyond progression (IBP) and those receiving non-immunotherapy beyond progression (NIBP). Survival outcomes and treatment safety were compared between these two groups. RESULTS: A total of 150 patients were included, with 111 NSCLC patients (IBP: n = 78, NIBP: n = 33) and 39 SCLC patients (IBP: n = 31, NIBP: n = 8). Significant differences in median progression-free survival (PFS) and overall survival (OS) were found in patients with driver gene-negative NSCLC (mPFS: 4.7 vs 1.3 months, HR = 0.29, P < 0.01; mOS: 11.03 vs 2.63 months, HR = 0.13, P < 0.001) and SCLC (mPFS: 3.9 vs 2.1 months, HR = 0.38, P = 0.02; mOS: 9.28 vs 2.27 months, HR = 0.23, P < 0.01). Additionally, among driver gene-negative NSCLC patients, achieving a partial response (PR) or stable disease (SD) during initial immunotherapy was associated with improved effectiveness of continued immunotherapy beyond progression. CONCLUSIONS: Continued immunotherapy as a second-line treatment may benefit patients with driver gene-negative NSCLC and SCLC who have progressed after initial immunotherapy.