ABL1 gene deletion without BCR/ABL1 rearrangement in a young adolescent with precursor B-cell acute lymphoblastic leukemia: clinical study and literature review..     ///    "however, it is plausible that ABL1 deletion without BCR/ABL1 rearrangement is a rare but recurrent genetic abnormality in precursor B-ALL patients. "    ///    " Entire ABL1 gene deletion without BCR/ABL1 rearrangement is a rare phenomenon, with only four cases previously reported. "    ///    Here we describe a fifth case of ABL1 deletion without BCR/ABL1 rearrangement in an adolescent patient with precursor B-cell lymphoblastic leukemia (B-ALL) and review the relevant literature. 