Three cases of Philadelphia (Ph) chromosome positive acute myeloid leukemia (AML) treated with imatinib mesylate (Glivec, STI571) and allogeneic hematopoietic stem cell transplantation after induction chemotherapy

The Ph-chromosome is the hallmark of chronic myelogenous leukemia (CML), but it has also been reported infrequently for de novo AML. This cytogenetic variant of AML is characterized by a poor prognosis associated with extraordinary drug resistance. Experience with the use of imatinib mesylate for Ph-chromosome-positive de novo AML is limited because of the rarity of the disorder. Thus, allogeneic hematopoietic stem cell transplantation (HSCT), as a post-remission therapy, should be considered. In three patients with Ph-chromosome-positive AML, we achieved complete remission with induction chemotherapy and the use of an imatinib cycle as an interim therapy. Subsequently, all patients received consolidation chemotherapy followed by imatinib cycles, bridging the time to allogeneic HSCT. All patients were successfully transplanted, and have been in excellent condition, with a median follow-up duration of 15 months (range, 2-25 months). We report on these cases and present the treatment strategy of induction chemotherapy, maintenance with imatinib mesylate, and final allogeneic HSCT as a representative paradigm for the treatment of Ph-chromosome-positive de novo AML.