Expression of CD38 has been found in chronic lymphocytic leukemia (CLL), acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), aggressive natural killer (NK) cell leukemia (ANKL), NK/T-cell lymphoma, mantle cell lymphoma (MCL), and Waldenström’s macroglobulinemia (WM) [42,43]. This evidence concerns the gene CD38 and aggressive behavior.