Cleaved Leukemic Blast Cells, Vacuolation and Pseudopodia-like Cytoplasmic Projections in Acute Myeloid Leukemia with

Generally, clefted lymphocytes can mainly occur in patients with Bordetella pertussis infection, follicular lymphoma, or less commonly in chronic lymphocytic leukemias. The presence of cleaved leukemic blast cells in cases with AML is quite rare. Additionally, in the absence of typical morphological findings (including blasts with hemophagocytosis, eosinophilia and micromegakaryocytes) in AML with TLS::ERG, the occurrence of cleaved blast cells, as well as vacuolation and cytoplasmic pseudopod formation in the present case is extremely uncommon. Moreover, CD56 expression in AML with t(16;21) has been suggested to connect with a poor prognosis, and may influence the CR duration and overall survival. Our present case presented partial expression of CD56 and bone marrow reexamination showed continuous CR for three months, but due to economic reasons, he did not continue follow-up examination, and the efficacy could not be evaluated. In brief, this case reminds us to recognize atypical morphologic features of clefted leukemic blasts and pseudopodia-like cytoplasmic projections in some subtypes of leukemias.