Efficacy and safety of G-CSF prophylaxis in patients with extensive-stage small cell lung cancer receiving chemoimmunotherapy.

Objectives: We aimed to evaluate the efficacy and safety of granulocyte-colony stimulating factor (G-CSF) prophylaxis during chemoimmunotherapy with carboplatin plus etoposide and atezolizumab in extensive-stage small cell lung cancer (ES-SCLC).

Methods: This retrospective, multicenter study enrolled ES-SCLC patients receiving carboplatin plus etoposide and atezolizumab, categorized into G-CSF and non-G-CSF groups. Demographic and disease-related data were collected. Response rates, progression-free survival (PFS), overall survival (OS), and toxicity were analyzed.

Results: Of 119 patients (median age: 63 years), the overall response rate (ORR) and disease control rate (DCR) were 72.3% and 81.5%, respectively. In the G-CSF group, the ORR was 76.4% compared to 60.0% in the non-G-CSF group (p = 0.33), and the DCR was 85.4% versus 70.0%, respectively (p = 0.46). Median PFS was 8.3 months (95% CI, 6.8-9.8) in the G-CSF group and 6.8 months (95% CI, 6.2-7.5) in the non-G-CSF group (p = 0.24). Median OS was 13.8 months (95% CI, 9.6-18.1) for the G-CSF group and 10.6 months (95% CI, 7.9-13.3) for the non-G-CSF group (p = 0.47). Grade 3 ≥ adverse events were similar between groups (49.4% vs. 33.3%, respectively, p = 0.12).

Conclusion: G-CSF prophylaxis can be safely used in ES-SCLC patients undergoing carboplatin plus etoposide and atezolizumab regimen without significantly altering efficacy or increasing toxicity.