Abstract
Lung cancer is the most common malignancy worldwide. Despite significant advances in diagnosis and treatment, mortality rates remain extremely high, close to incidence rates. Several targeted therapies have been recently introduced for the treatment of non-small cell lung cancer (NSCLC), the most common type of lung cancer. Nivolumab, a monoclonal antibody that targets programmed death-1 (PD-1), was the first immune checkpoint inhibitor approved for the treatment of patients with advanced/metastatic NSCLC not responding to platinum-based chemotherapy. Biomarkers predicting response to these therapies would allow early identification of non-responders and timely implementation of appropriate combination strategies, avoiding inadequate and expensive therapies. The role of the neutrophil to lymphocyte ratio and other blood cell count indexes as possible biomarkers of response has been recently investigated. We discuss the encouraging results reported on the topic, provide new data from our personal experience, and discuss opportunities for further research.