Blood Stem Cell Versus Bone Marrow Transplantation: A Critical Appraisal
I. INTRODUCTION Transplantation of hematopoietic stem/progenitor cells is essential for survival if highdose myelotoxic anticancer therapy has caused permanent marrow ablation or damage severe enough to produce a dangerously prolonged period of neutropenia that cannot be sufficiently shortened with growth factor administration. If the transplanted cells are autologous, one must have already anticipated the necessity for transplant and collected the cells prior to the administration of high-dose therapy. If the cells are to be allogeneic, a suitable donor must have been identified prior to the high-dose therapy. Clinical results from dose-escalation studies have improved the accuracy of predictions that marrow ablation or prolonged marrow suppression will result after a particular high-dose regimen is given, but the variable health of stem cells, especially in patients who have already been treated with myelotoxic agents before high-dose therapy administration, precludes precise predictions.