New strategies of allogeneic hematopoietic stem cell transplantation with the use of haploidentical donors

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for patients with hematological diseases. The probability of finding a human leucocyte antigen (HLA) identical donor among family members is around 25% and 30% that of having a full matched unrelated donor in the registry. For patients lacking a full matched sibling or unrelated donor, several strategies are available to benefit of mismatched donors, such as haploidentical family donors. Recently, novel strategies to control graft-versus-host disease and facilitate engraftment extended the use of unmanipulated haploidentical stem cell transplantation, both in the myeloablative and reduced intensity conditioning regimen and using bone marrow or peripheral blood stem cell as stem cell source. This review presents the different transplant platform available in the setting of haploidentical transplantation for patients with hematological malignancies. It provides also criteria for the choice of the haploidentical donors. Prospective comparative studies are required to establish the relative efficacy of different transplant platforms. Moreover, center experience and facilities and the availability of clinical trials should be taken in consideration for the appropriate algorithm of donor choice.