Outcomes of Combined Atezolizumab Plus Chemotherapy in Non-small Cell Lung Cancer Patients in Clinical Practice

Background/Aim: Atezolizumab, one of the anti-PD-L1 antibodies, targets PD-L1 expressed on cancer cells and antigen-presenting cells. This immune checkpoint inhibitor is now commonly used in combination with chemotherapy. The objectives of this study were to confirm the treatment outcomes of combined atezolizumab plus chemotherapy, and to identify prognostic factors, with a particular focus on the impact of the site of metastasis in real-world clinical practice. Patients and Methods: A retrospective review of clinical information on non-small cell lung cancer patients who received combined atezolizumab plus chemotherapy from May 2018 to August 2024 at our 11 hospitals was conducted. Results: The 141 patients evaluated had a median progression-free survival of 8.0 months and a median overall survival of 19.0 months. Multivariate analyses showed that 'absence of liver metastases', 'absence of adrenal metastases', 'first-line combined atezolizumab plus chemotherapy', and 'good performance status' were associated with progression-free survival and overall survival. Immune-related adverse events were observed in 27.7% of patients, with grade 3 or higher in 9.9% of patients, and grade 5 in 2.1% of patients. Conclusion: Efficacy and immune-related adverse events associated with the combination of atezolizumab and chemotherapy in non-small cell lung cancer patients were comparable to previous clinical trials. To ensure that appropriate patients receive the most effective treatment, it is important to identify detailed prognostic factors, including clinical information, such as the affected metastatic organs. Continued research and further accumulation of knowledge in this area are eagerly anticipated.