The use of tumor PD-L1 expression as a biomarker has been studied extensively.[13] However, there is a general need to better identify responders, as only 25% to 30% of patients under checkpoint treatment show long-term responses and these might not be exclusively identified by PD-L1 expression.[14,15] It is an unmet need for biomarkers that will identify patients more likely to respond to PD-1/PD-L1 blockade as well as other immunotherapeutics. The gene discussed is CD274; the disease is neoplasm.