Abstract
PURPOSE: The aim of this study was to assess the effectiveness and tolerability of atezolizumab plus carboplatin and etoposide combination chemotherapy in elderly patients with extensive-disease (ED) small-cell lung cancer (SCLC). METHODS: This retrospective study evaluated 65 SCLC patients who received atezolizumab, carboplatin, and etoposide for ED-SCLC in nine study institutions between August 2019 and September 2020. Clinical efficacy, assessed according to response rate and survival, and toxicity were compared between the elderly (n = 36 patients; median age: 74 years [range: 70-89 years]) and the non-elderly group (n = 29 patients; median age: 67 years [range: 43-69 years]). RESULTS: The response rate was 73.8% (80.5% in the elderly group and 65.5% in the non-elderly group). There was no significant difference in both the median progression-free survival (5.5 months vs. 4.9 months, p = 0.18) and the median overall survival (15.4 months vs. 15.9 months, p = 0.24) between the elderly group and the non-elderly group. The frequencies of grade ≥3 hematological adverse events in the elderly patients were as follows: decreased white blood cells, 36.1%; decreased neutrophil count, 61.1%; decreased platelet count, 8.3%; and febrile neutropenia, 8.3%. One treatment-related death due to lung infection occurred in the elderly group. CONCLUSION: Despite hematologic toxicities, especially decreased neutrophil count, atezolizumab, carboplatin, and etoposide combination chemotherapy demonstrates favorable effectiveness and acceptable toxicity in elderly patients. Thus, atezolizumab plus carboplatin and etoposide could be the preferred standard treatment modality for elderly patients with ED-SCLC.