Role of autologous stem cell transplantation in chronic lymphocytic leukemia.

Autologous hematopoietic stem sell transplantation is increasingly considered for treatment of patients with high-risk chronic lymphocytic leukemia. Patients not eligible for allogeneic hematopoietic stem cell transplantation with poor prognosis disease, documented chemosensitivity, and a minimal tumor burden at the time of hematopoietic stem cell transplantation can be treated with autologous hematopoietic stem cell transplantation currently using peripheral blood stem cells. Different purging methods to obtain sources of stem cells free of tumor contamination are currently being evaluated. Major concerns are judicious selection of which patients may benefit from this approach, the subsequent risk of relapse of disease, and the long-term risk of development of secondary malignancies, including myelodysplastic syndrome and acute myelogenous leukemia. Recognizing and reducing the risk factors that contribute to relapse and complications of the procedure should improve outcome after autologous hematopoietic stem cell transplantation. With the increasing use, increasing effectiveness, and low treatment-related mortality associated with nonmyeloablative conditioning regimens, the question of whether a patient should be offered autologous or allogeneic hematopoietic stem sell transplantation can be a difficult one. Defining salvage settings for relapse and implementing a tandem autologous/allogeneic hematopoietic stem cell transplantation approach may provide a method to improve outcome for selected patients.