Immunotherapy in non-metastatic non-small cell lung cancer: Can the benefits of stage IV therapy be translated into earlier stages?

Over the last decade, several steps forward in the treatment of patients with stage IV non-small cell lung cancer (NCSLC) were made. Examples are the use of pemetrexed, pemetrexed maintenance therapy, or bevacizumab for patients with nonsquamous NSCLC. A big leap forward was the use of tyrosine kinase inhibitors in patients selected on the basis of an activating oncogene, such as epidermal growth factor receptor () activating mutations or anaplastic lymphoma kinase () translocations. However, all of these achievements could not be translated into survival benefits when studied in randomized controlled trials in patients with nonmetastatic NSCLC. Aside from chemotherapy and targeted therapy, immunotherapy has become the third pillar in the treatment armamentarium of advanced NSCLC. Antigen-specific immunotherapy (cancer vaccination) has been disappointing in large phase III clinical trials in stages I-III NSCLC. Based on the recent breakthroughs with immune checkpoint inhibitor immunotherapy in metastatic NSCLC, much hope currently rests on the use of this approach in patients with stage I-III NSCLC as well. Here we give a brief overview of how most new therapeutic approaches for advanced NSCLC failed in other stages, and then elaborate on the role of immunotherapy in patients with stage I-III NSCLC.