- The advent of recombinant colony-stimulating factors (CSFs) for clinical use in neutropenic states has focused attention on their potential benefit in combination with high dosage cancer chemotherapy (HDCT). HDCT has been used with substantial success for salvage and consolidation therapy and, more recently, for initial therapy. However, its use has been associated with profound myelosuppression. Rescue techniques such as bone marrow stem cell transplantation and/or peripheral blood progenitor cell support may well shorten myelosuppression but do not eliminate it completely. Granulocyte-macrophage CSF and granulocyte CSF have been the most extensively investigated CSFs in clinical trials. Following marrow transfusion, administration of CSFs may decrease the duration of neutropenia, reduce the need for antibiotics, and shorten hospitalisation. Although CSFs were initially used only to enhance bone marrow recovery after marrow infusion, other new applications were subsequently discovered. CSFs may be used to mobilise peripheral blood progenitor cells for bone marrow support, or even for marrow stem cell substitution. In patients with graft failure, GSFs have been used in an attempt to rescue the failing marrow. As experience with these agents has accumulated, the optimal use of each single CSF, such as dosage, schedule, specific treatment regimen and costs, has become better defined. As a result, protocols for HDGT incorporating the use of CSFs are becoming routine. Such use of CSFs has made HDCT a procedure that is better tolerated, more convenient to use on a large scale, and probably cheaper.