We have prospectively performed peripheral blood stem cell autotransplants in six patients with hematological malignancies on an entirely outpatient basis. Patients were conditioned with high-dose melphalan and received a median of 4.2 x 10(8)/kg non-cryopreserved, non-purged mononuclear cells, containing a median of 3.9 x 10(6)/kg CD34 + cells. The median time to achieve > 500 granulocytes/microl was 21 days, with a range of 16 to 40, whereas the median time to achieve > 20,000 platelets/microl was 38 days, with a range of 21 to 48. Only three patients were transfused with platelets whereas packed red blood cells were transfused in two. All patients survived 60 days after the autograft and three are alive at 450, 690, and 1,950 days after the autotransplant. One patient was given an allogeneic bone marrow transplant when relapsing after the autotransplant. One patient had to be admitted to the hospital on day +10 because of fever. A median of 6,500.00 USD per patient was calculated as the total cost of each outpatient autotransplant. Since outpatient autologous transplants with non-frozen PBSC are feasible, restrictions to PBSC autotransplant programs may be overcome and costs may be diminished.