PRDM1 and aneurysmal bone cyst: Despite their phenotypic reminiscence of post-GC B-cells (29, 68), PT-DLBCL have a pattern of DNA gains and losses that is different from ABC DLBCL, lacking gains of 3q and 18q (BCL2, NFATC1) and losses of 6q (PRDM1 and TNFAIP3) (57).