Autologous stemcell transplantation has been successfully used in treatment of various hematologicalmalignancies and solid tumors in children and adults. Published data have confirmed that bone marrow harvests and peripheral blood stem cell collections frequently contain a significant number of tumor cells. Contaminating tumor cells can contribute to the disease relapse in posttransplant period, so attempts are made to eliminate contaminating tumor cells from autografts. In the case of allogenic transplantation, T-lymphocytes depletion from graft decreases the risk of the graft versus host disease after transplantation. In this article we comment techniques available and method used for elimination of tumor cells. Commentary is aimed on potential benefits and risks of every method.

        Key words: ex vivo purging, bone marrow transplantation, minimal residual disease.