Treatment patterns and survival outcomes in patients with small-cell lung cancer following failure of first-line platinum-based chemotherapy.

Objective: Small-cell lung cancer (SCLC) is an aggressive malignancy with limited treatment options, especially after the failure of first-line (1L) platinum-based chemotherapy. This study evaluated the treatment patterns and survival outcomes of Taiwanese patients with SCLC following 1L treatment failure, focusing on the effects of treatment-free interval (TFI).

Methods: This retrospective study enrolled 287 patients with SCLC from 2012 to 2021. Data on clinical characteristics, systemic treatments after 1L failure, and survival status were collected. Progression-free survival (PFS) and overall survival (OS) were examined in analyses stratified by TFI. TFI < 90 days and ≥ 90 days denoted resistant relapse and sensitive relapse, respectively.

Results: Second-line (2L) and third-line (3L) chemotherapy was administered to 76% and 54.1% of patients, respectively. Topotecan was administered to 25.4% of patients, primarily those with TFI 90-179 days. Platinum rechallenge was administered to 8.4% of patients, primarily those with TFI ≥ 180 days. The median PFS of patients with 2L treatment was 2.3 months (95% CI 2.2-2.6), and the median OS was 5.1 months (95% CI 4.3-6.2). Patients with TFI ≥ 90 days had significantly longer PFS (2.6 vs 2.2 months, P = 0.011) and OS (9.6 vs 4.0 months, P < 0.0001) than did those with TFI < 90 days. Platinum rechallenge showed similar efficacy to topotecan in patients with sensitive relapse (3.0 vs 2.7 months, P = 0.61).

Conclusions: Survival outcomes in patients with relapsed SCLC remain poor, particularly in those with platinum-resistant relapse. Our findings highlight the importance of optimizing 1L treatment for delaying disease progression. More effective 2L therapies should be developed to improve survival outcomes in patients with relapsed SCLC.