CARD11 and aneurysmal bone cyst: Because mutated CD79B and MYD88 are insufficient to activate the BCR signaling cascade themselves, the mechanism of activation of the BCR signaling cascade in ABC-DLBCL without activating CARD11 mutations (CARD11wt ABC-DLBCL) remains unclear, and an additional non-genetic driving mechanism has been postulated to induce the ABC-DLBCL phenotype (Wilson et al., 2015).