LAUSR

Pediatric Philadelphia chromosome positive (Ph+) acute T-cell lymphoblastic leukemia can mimic chronic myelogenous leukemia (CML) in T-lineage blast crisis (BC). Differentiating the 2 is critical in guiding therapy as most children with de novo Ph+ acute T-cell lymphoblastic leukemia are treated with chemotherapy and tyrosine kinase inhibitors, whereas T-lineage BC of CML can include hematopoietic stem cell transplantation. We present a unique case of CML in T-lineage BC. The patient was treated with induction chemotherapy plus imatinib followed by matched unrelated donor hematopoietic stem cell transplantation. She is currently off all medications and in complete disease remission.