CTLA4 and lung carcinoma: Programmed cell death protein 1 (PD-1) antibodies [20] as well as PD-L1 antibodies and cytotoxic T-lymphocyte-associated Protein 4 (CTLA-4) inhibitors [21] led to improved PFS and OS in patients with advanced or recurrent lung cancer [22,23] and are approved for routine use in NSCLC in various combinations.