Which chemotherapy regimen might be the best for the second-line treatment of patients with small-cell lung cancer?

Introduction. Small-cell lung cancer (SCLC) is an aggressive disease. Despite the first-line (1L) chemotherapy, almost all patients need the second-line (2L) treatment within a year. However, there is no general agreement on standard 2L treatment. This study aimed to determine outcomes obtained with different treatment regimens, factors affecting the results, and standard approach in the 2L treatment of SCLC. Material and methods. This was a singlecenter, retrospective, cross-sectional, cohort study. The inclusion criteria were age >= 18, histologically or cytologically proven SCLC, progressive disease after 1L treatment, and receiving 2L chemotherapy. Results. A total of 89 patients were assessed in this study. The patients were classified into three groups: 35 patients received the combination of doxorubicin, cyclophosphamide, and vincristine (CAV), 24 patients received single-agent topotecan (TPT), and 30 patients received numerous different treatment schemes. The overall response rate (ORR), disease control rate (DCR), median progression-free survival (PFS), and median overall survival (OS) were 19.1%, 46.1%, 3.5 months, and 6.4 months, respectively. Although no statistically significant difference was found between the three groups in PFS (p = 0.195) and OS (p = 0.286), there were numerically better outcomes with CAV. In univariate analyses, the comorbidity was related to decreased PFS (p = 0.044). However, this relationship could not maintain its statistical significance in multivariate analysis (p = 0.224). Conclusions. It is still impossible to make a standard recommendation for the 2L treatment of patients with SCLC. However, the numerical difference in favor of CAV may be clinically meaningful.