The Clinical Features And Laboratory Findings Of Mixed Phenotyping Acute Leukemia In14Children

Background:Mixed phenotyping acute leukemia (MPAL) represents a heterogeneous category of rare in acute leukemia. As MPAL represent only3%to5%of acute leukemias occurring in patients of all ages, the optimal therapeutic approach to these cases in pediatric patients has not been defined.Methods:To characterize the biology and optimal therapy of MPAL in children, we reviewed the pathologic and clinical features, including response to therapy, of14patients with MPAL.Results:Morphology was consistent with acute lymphoblastic leukemia (ALL;10/14) and acute myeloid leukemia (AML;4/14). Immunophenotyping disclosed B+myeloid (4/14), T+myeloid (4/14), B+T (4/14) and trilineage (2/14) combinations. Cytogenetics evidenced t(9;22)/Ph+(1/11),11q23/MLL rearrangements (1/11), other aberrant (5/11), or normal (4/11) karyotypes. Nine cases received ALL therapy with7/9CR,2cases received AML with1/2CR. Three cases gave up treatment after initial diagnosis. One case treated as ALL got a long term remission,1case treated as AML stayed alive after transplantation. Original resistance and relapse are the main reasons for death. Overall survivals for1year and3years were28.5%and7%, respectively.Conclusions:Our study confirmed that MPAL in children is a poor-risk disease when treated with the strategies we used in our patients.