CD274 and diffuse large B-cell lymphoma: In summary, the MGZLs in this session presented in younger patients at lower clinical stages, frequently showed PDL1 positivity, and demonstrated a PMBL-like GE signature in 75% of cases, in contrast with the non-mediastinal GZLs, which developed in older patients with more advanced clinical stages, and showed a DLBCL-like GE signature in at least 50% of samples.