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.