To determine if peripheral blood cells (PBC) apheresed following mobilization with chemotherapy and recombinant growth factor further enhances hematopoietic recovery over that achieved with autologous bone marrow (ABM) and recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) ÷ 14 patients with metastatic solid tumors were supported by ABM and GM-CSF during the first course of high doses of cyclophosphamide, etoposide, and cisplatin (CVP) and by mobilized PBC with ABM and GM-CSF during the second course. Each patient served as his or her own control. Identical doses of CVP were given in both courses: cyclophosphamide 5.25 g/m2, etoposide 1200 mg/m2, and cisplatin 165–180 mg/m2. PBC were collected on day 10 after mobilization with cyclophosphamide intravenously (IV) and doxorubicin and GM-CSF as a daily four-hour IV infusion at 0.6 mg/m2 for 14 days. The duration of absolute neutropenia under 0.1 × 109/L was not statistically significant between cycles but platelet recovery to both 0.02 × 1012/L and 0.05 × 1012/L was enhanced. Additional studies on different approaches to further enhance the reconstitutive powers of peripheral blood with lesser toxicity include studies with G-CSF administration and combination GM-CSF and G-CSF for six days prior to apheresis. These approaches were equivalent to chemotherapy and growth factors but were less toxic.