Considering the great levels of Programmed Death Ligand 1 (PD-L1) expression in TETs, ranging from 23% to 92% for thymomas and from 34% to 88% for TCs, Programmed Death 1 (PD-1)/PD-L1 inhibitors have shown a very promising clinical activity [23,24]. The gene discussed is CD274; the disease is thymoma.