Copy number losses of HLA class I and II genes resulting in decreased expression of MHC I and II and limited tumor-antigen presentation to TILs, gains and amplifications of CD274 and PDCD1LG2 with their increased transcription and PD-L1/PD-L2 protein expression implicating immune escape, as well as T-DLBCL’s location in an immune-privilege site are all hallmarks of T-DLBCL and highlight the significance of the TME and host-related factors [45,47,99,146]. This evidence concerns the gene CD274 and diffuse large B-cell lymphoma.