Immune checkpoint inhibitors in the first-line treatment of metastatic small-cell lung cancer

Small-cell lung cancer is the most aggressive form of lung cancer. Most patients are diagnosed at a late disease stage when the prognosis is poor. The treatment algorithm for small-cell lung cancer remained unchanged for years, with chemotherapy as the first-line option. However, progress has been made with the recent development of immune checkpoint inhibitors, two of which - atezolizumab and durvalumab - have been approved in combination with chemotherapy as first-line treatment for advanced small-cell lung cancer. This review presents detailed data concerning the efficacy and safety of atezolizumab and durvalumab from both registration trials and real-world studies, as well as the results of clinical trials of other immune checkpoints inhibitors. Finally, the issue of identifying biomarkers to predict the efficacy of immunochemotherapy is discussed.