Efficacy and safety of carboplatin and etoposide in older extensive-stage small-cell lung cancer patients with a poor performance status

Carboplatin plus etoposide is a standard treatment for older extensive-stage small-cell lung cancer (ES-SCLC) patients with performance status (PS) 2. However, older patients often exhibit poor PS (3, 4), and the treatment effect in them is poorly understood. To determine the therapeutic efficacy and safety of carboplatin plus etoposide therapy for this population, we retrospectively analyzed 63 patients with ES-SCLC with PS ≥2, aged ≥71 years, who had received first-line carboplatin plus etoposide therapy. We compared the treatment efficacy and safety in patients with baseline PS 2 versus those with PS 3–4. In the PS 2 (38 patients) and PS ≥3 (25 patients) groups, the overall response rate was 71.1% and 72.0%, median progression-free survival was 4.6 and 3.1 months, and overall survival was 7.7 and 5.1 months, respectively. PS improved to 0–1 post-treatment in 65.8% and 48.0% of the patients in the PS 2 and PS ≥3 groups, respectively. Patients with PS ≥3 showing improved PS had a progression-free survival of 6.1 months. A higher incidence of grade ≥3 decreased neutrophil counts, febrile neutropenia, and treatment-related death was observed in the PS ≥3 group. The progression-free survival of patients administered prophylactic granulocyte colony-stimulating factor (G-CSF) was 5.2 and 6.1 months in the PS2 and PS ≥3 groups. Overall, carboplatin plus etoposide therapy provided comparable tumor shrinkage, but shorter progression-free and overall survival in older ES-SCLC patients with PS ≥3 than in those with PS 2. Thus, supportive care, such as prophylactic G-CSF administration, may be necessary to ensure safety and survival.