In cases of DLBCL non‐responding to RIS and rituximab, as well as “non‐DLBCL” monomorphic PTLD and primary CNS‐lymphoma, polychemotherapy is suggested, mostly consisting of R‐CHOP, CHOP, and COP regimens.35, 62. The gene discussed is DDIT3; the disease is post-transplant lymphoproliferative disease.