PDCD1LG2 and primary central nervous system lymphoma: Likewise, primary mediastinal B-cell lymphoma (PMBCL), primary central nervous system lymphoma (PCNSL), gray zone lymphoma (GZL), and primary testicular lymphoma (PTL) are thought to have T-cell-inflamed microenvironments, with upregulation of PD-L1/PD-L2, and favorable clinical responses to ICI therapy have been observed in these diseases [70,71,72,73,74,75].