Therefore, in this study, we prospectively analyzed bone marrow samples from 386 pediatric BCP-ALL patients at diagnosis and at days 15 and 33 of the treatment according to ALL-IC BFM 2009 protocol to determine the association of CRLF2 protein expression on the surface of leukemic cells with blast clearance in the bone marrow and treatment outcomes. This evidence concerns the gene CRLF2 and acute lymphoblastic leukemia.