Akademik Veri Yönetim Sistemi
Oncologist, cilt.31, sa.4, 2026 (SCI-Expanded, Scopus)
Abstract Aim IMpower133 was designed with 4 cycles of chemoimmunotherapy with atezolizumab, unlike many other studies permitted 6-cycle induction. This study aimed to compare the efficacy and safety of a 4-cycle regimen with an extended 6-cycle regimen of carboplatin, etoposide, and atezolizumab in the first-line treatment of extensive-stage small-cell lung cancer (ES-SCLC). Methods This retrospective multicenter study was conducted across 13 oncology centers in Turkey. A total of 181 patients with ES-SCLC who received first-line treatment with chemotherapy plus atezolizumab were analyzed and grouped into those receiving 4 cycles (n = 101) and 6 cycles (n = 80) of treatment. Results The median follow-up time was 20.9 months. The objective response rates were similar between the 4- and 6-cycle groups (79.2% vs 78.8%, P = .940). The disease control rates were also comparable (84.2% vs 86.3%, P = .940). The median progression-free survival (PFS) was 6.3 months in the 4-cycle and 8.1 months in the 6-cycle group (P = .357). The median overall survival (OS) was 16.6 months for the 4-cycle and 13.6 months for the 6-cycle group (P = .583). Intracranial progression was higher in the 4-cycle group (50.0% vs 25.5%, P = .007). Immune-related adverse events were similar between the groups. Conclusion This is one of the largest real-world datasets comparing the efficacy and safety of 4 versus 6 cycles of induction chemoimmunotherapy. Although there were no significant improvements in PFS or OS, the 6-cycle regimen was associated with a lower observed rate of intracranial progression, predominantly among patients without baseline brain metastases. Further studies are needed to identify this subject in future.