Mobilisation of Ph-negative peripheral blood stem cells in CML with idarubicin and cytarabine.

Recent interest in autologous transplantation in chronic myeloid leukaemia (CML) has focused on attempts to select out putatively normal Ph-negative progenitor cells for subsequent reinfusion after high dose therapy. One way in which this may be achieved is by collecting peripheral blood stem cells (PBSCs) during the early regenerative phase following chemotherapy when Ph-negative cells seem to have a short term proliferative advantage. Data now suggest that it is possible to collect Ph-negative (and occasionally PCR negative) progenitor cells in a significant number of CML patients, a proportion of whom will go on to achieve a cytogenetic remission post-autografting. The durability of these remissions and the effect on long term survival remain to be established and at present this form of therapy should be reserved for those unsuitable for allogeneic transplantation who have failed to achieve a major cytogenetic response to interferon-alpha.