How I approach hematopoietic stem cell transplantation for CML in a TKI world

Following the introduction of tyrosine kinase inhibitors (TKI), the number of patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) for chronic phase chronic myeloid leukemia (CP-CML) has dramatically decreased. Imatinib was the 1st TKI introduced into the clinical arena, predominantly utilized in the 1st line setting. In cases of insufficient response, resistance, or intolerance, CML patients can subsequently be treated with a 2nd, 3rdor 4th generation TKI. However, despite the approval of 1st, 2nd, 3rd, 4th generation TKI allo-HSCT still remains indicated for a minority of CML patients. Here, we discuss the indications in the era of TKI through different cases representing the clinical situations for which allo-HSCT remains the best option. We also propose our transplant strategy to decrease transplant-related morbidity, particularly graft-versus-host disease (GvHD), and mortality in the particular context of CML, a disease that is one of the most sensitive to immune cellular therapy, allowing the use of a combination of donor lymphocyte infusion (DLI) and TKI for post-transplant molecular progression.