AKT1 and post-transplant lymphoproliferative disease: The most common copy number aberration in EBV(+) PTLD is the gain/amplification of 9p24, whereas in EBV(–) PTLD, it includes gain of 3/3q and 18q, loss of 6q23/TNFAIP3, and loss of 9p21/CDKN2A TP53 mutations were more frequent in EBV(–) PTLD than EBV(+) PTLD and IC-DLBC. Compared with EBV(+) PTLD, EBV(–) PTLD and IC-DLBC have more frequent gene mutations associated with the NF-κB pathway. EBV(+) PTLD has a constitutive activation of the PI3K/Akt/mTOR pathway.