Mobilisation and Reinfusion of Philadelphia Negative Peripheral Blood Mononuclear Cells in Chronic Myeloid Leukaemia with Hydroxyurea and G-CSF

Abstract

Unmanipulated autologous transplantation of marrow orperipheral blood stem cells has been performed in small numbers of patients with CML for many years. More recently there has been interest in attempting to 'purge' the autograft of clonal cells as defined by the presence of the Philadelphia chromosome or BCR-ABL rearrangement. One method by which this might be achieved in vivo has been developed in Genoa and involves the administration of high dose chemotherapy and G-CSF followed by peripheral blood stem cell collection. These collections are frequently devoid of Philadelphia positive cells and the hope is that this will enhance the effects of subsequent autograft. We have investigated the use of a less toxic regimen for this procedure using oral hydroxyurea and G-CSF. In this review we describe the background to autografting in CML and the development of strategies to mobilise Philadelphia negative cells into the peripheral blood. We go on to present an update of our data using hydroxyurea and discuss some of the practical and theoretical issues behind the procedure.

Key Words:

• Chronic myeloid leukemia
• autologous transplantation
• hydroxyurea
• Philadelphia negative stem cells
• mobilisation of stem cells
• peripheral blood stem cells
• PBSC