CD274 and lung carcinoma: The timeline diagram of the keywords reveals three primary phases in PD-1/PD-L1 immunotherapy research: (i)immunotherapy safety studies (2010–2015): During this period, the FDA approved the first PD-1/PD-L1 blockers for advanced NSCLC treatment. The majority of research devoted to the treatment of lung cancer is concerned with first-line therapies such as chemotherapy and related drugs.