Role of hematopoietic stem cell transplantation in Philadelphia chromosome-positive acute lymphoblastic leukemia: a report of 2 unique cases

We report, to our knowledge, the first reported case of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) developing 26 years after allogeneic stem cell transplantation for chronic myeloid leukemia (CML). The second case involved de novo Ph+ALL that developed 16 years post-autologous stem cell transplantation in sustained molecular remission. These cases illustrate and raise some key issues in the management of patients with Ph+ leukemias, including the role of hematopoietic stem cell transplantation, tyrosine kinase inhibitors,and long-term post-transplantation follow-up.