Background: Small cell lung cancer (SCLC) is a malignant carcinoma characterized by high proliferative rate and early metastatization with limited treatment options and poor prognosis. The approval of ICIs has established a new standard of care for extensive-stage (ES)-SCLC (5). Atezolizumab, an anti PD-L1 monoclonal antibody, has been the first immune checkpoint inhibitor (ICI) to be approved for SCLC patients. This study aims to retrospectively evaluate the real-world effectiveness and safety of atezolizumab in a cohort of patients with ES-SCLC. Methods: We conducted a monocentric retrospective analysis of SCLC patients who received atezolizumab in addition to chemotherapy, between January 2020 and December 2023. Study design endpoints included progression-free survival (PFS), overall survival (OS), and adverse events. Results: A total of 134 patients were included in this study. Out of 134 patients who began the CEA protocol, 100 continued maintenance. Currently, 25 are alive, 17 still on atezolizumab, 5 on second-line therapy, and 3 receiving best supportive care. The median age was 65 years. Patients received a median of four cycles of CEA (range 1–6 cycles), while the median number of atezolizumab maintenance cycles was eight (range 0–75). The overall median survival was 15 months, with patients who received more than 30 cycles of atezolizumab showing OS of 46.7% at 48 months. Common adverse events included skin disorders, pneumonitis, colitis, alanine, and aspartate deaminase increment, dysthyroidism, and blood disorders with only 3% of patients experiencing grade 3 or higher toxicities. Conclusions: In this real-world cohort, atezolizumab demonstrated comparable effectiveness to clinical trial results, with a manageable safety profile. These findings support the use of atezolizumab as a viable treatment option for ES-SCLC in routine clinical practice.
Pagliaro et al. (2025) studied this question.