In this week's episode we'll discuss if fractionated dosing of gemtuzumab ozogamicin provide additional benefit over a single dose in older adults with AML. Then, we'll consider how the loss-of-function of ENT3 drives histiocytosis. Researchers describe a novel pathway leading to histiocytosis that involves hyperactivation of TLR-MAPKinase signaling. This suggests a potential benefit of MAPKinase -directed targeted therapy in a range of histocytoses. Finally we'll discuss unraveling resistance mechanisms to anti-CD20 treatments in B-cell malignancies. Through alternative splicing, the MS4A1 gene encoding human CD20 generates multiple mRNA isoforms with distinct 5’ untranslated regions.