Single-agent chemotherapy compared with combination chemotherapy as second-line treatment in extensive-stage small cell lung cancer: a retrospective analysis

Objective This retrospective analysis evaluates the clinical outcomes of extensive-stage small cell lung cancer (SCLC) patients who received second-line chemotherapy after platinum-based first-line chemotherapy, especially focusing on efficacy and toxicity between single-agent and combination chemotherapy. Methods We retrospectively reviewed 193 patients who received second-line chemotherapy for extensive-stage SCLC. Patients relapsing or progressing beyond 90 days were defined as sensitive recurrence patients, and below 90 days as refractory recurrence patients. Survival curves were plotted using the Kaplan–Meier method. The Cox proportional hazard model was used for multivariate analysis. Results 138 patients received combination chemotherapy and 55 received single-agent treatment. The objective response rate (ORR) was 25.4 % in the combination group and 9.1 % in the single-agent group ( p = 0.012). The disease control rate (DCR) was 65.2 and 34.5 %, respectively, ( p < 0.001). The progression-free survival (PFS) was 3.80 months in the combination group and 2.13 months in the single-agent group ( p = 0.001). In the sensitive recurrence group, the median PFS was 3.80 months in combination group and 3.23 months in single-agent group ( p = 0.092). In the refractory recurrence group, the median PFS was 2.83 and 1.30 months, respectively ( p = 0.001). The grade III/IV toxicity in single-agent group is much lower than the combination group (56.4 vs. 74.6 %, p = 0.013). Conclusion Our retrospective data suggest a potential role of prolonging the PFS for combination treatment in extensive-stage SCLC second-line treatment, especially for the refractory recurrence patients, but with more toxicity as compared to single-agent.