BCL2 and aneurysmal bone cyst: In addition, it has been proposed that the poor prognosis of ABC vs. GCB type in DLBCL may be largely explained by MYC/BCL2 double-expression rather than COO per se [26], although COO assignment using an RNA-based expression platform designed for formalin-fixed paraffin-embedded tissue appears to support the prognostic impact of COO independent of MYC/BCL2 double-expression [31].