Schema of study design. Eligible patients were registered and PBPCs were mobilized. Before initiating leukapheresis, patients were randomized to one of the two treatment arms. All patients received high-dose chemotherapy followed by an infusion of either CD34-selected or unselected PBPCs, with GM-CSF administered posttransplant. The primary study period was completed at 6 months posttransplant with follow-up currently at 1 year posttransplant. Additional follow-up is planned on a yearly basis.