Using a lymphoablative, non-myeloablative stem cell trasplantation (NST) program, 25 allografts were prospectively given to 24 patients with acute myelogenous leukemia (AML) eligible for conventional allografting; two individuals had secondary forms of AML. The median age of the patients was 35 years, with a range of 12 to 56. All patients engrafted; median time to achieve an absolute neutrophil count Ͼ0.5 x 10 9 /L was 12 days (range 0-26), whereas the median time to a platelet count Ͼ20 x 10

more »

... /L was 13 days (range 0-26). Patients developed chimerism 15 to 100 (median 30) days after the allograft. The follow-up periods range between 33 and 2664 days (median 450). The median post-transplant overall survival has not been reached and is above 89 months, whereas the 89-month both, overall and progression-free survival is 56%, the 683-day survival being 66%. In 14 grafts (56%) acute GVHD ensued; in 12 cases grades I-II and in 2 cases grade IV which was fatal in both. In 9/20 grafts (45%) limited chronic GVHD developed. In 22 cases (88%), the procedure could be completed fully on an outpatient basis. The 100-day and the transplant-related mortality were both 8%. The median cost of the allografts until day 100 was 20 000 USD. NST appears to be an effective additional therapeutic option for patients with AML in remission and a matched donor available.