Summary:We analyzed predictive factors for the outcome of 113 acute myeloid leukemia patients receiving reduced-intensity conditioning prior to allogeneic hematopoietic stem cell transplantation (HSCT). Patients were ineligible for conventional-intensity HSCT. Conditioning consisted of fludarabine and 50% of the conventional dose of busulfan (n ¼ 93) or total body irradiation (n ¼ 20). The source of stem cells was blood in 102 patients, marrow in 10, and both in one. In total, 50 (44.2%) donors were HLAmatched siblings, 50 (44.2%) unrelated fully matched and 13 (11.5%) partially mismatched family (n ¼ 1) or unrelated (n ¼ 12) donors. In all, 107 (94.6%) patients showed neutrophil and platelet engraftment after a median time of 13.5 and 13 days. The probabilities of event-free survival (EFS) (median follow-up: 12 months) were 49% for patients with less than 5% blasts in the marrow, 24% for patients with 5-20% blasts (P ¼ 0.002) and 14% with 420% blasts (Pp0.001). Death occurred because of relapse in 29 patients (25.6%), infection in 12 patients (10.6%), acute graft-versus-host disease in eight patients (7.0%) and organ toxicity in nine patients (7.9%). In multivariate analysis, higher number of blasts in the marrow, alternative donors and low Karnofsky performance score were independent adverse prognostic factors for EFS.

The clinical results in 107 patients receiving a peripheral blood stem cell (PBSC) graft mobilized by granulocyte colonystimulating factor (G-CSF) from HLA-A, -B, and -DR-compatible unrelated donors were compared to 107 matched controls receiving unrelated bone marrow (BM) transplants. Engraftment was achieved in 94% of the patients in both groups. The PBSC graft contained significantly more nucleated cells, CD34 ؉ , CD3 ؉ , and CD56 ؉ cells (P < .001), and resulted in a significantly shorter time-to-neutrophil (15 versus 19 days) and platelet engraftment (20 versus 27 days), compared to the BM control group (P < .001). Probabilities of acute graft-versus-host disease (GVHD) grades II to IV were 35% and 32% (not significant [NS]) and of chronic GVHD 61% and 76% (NS) in the PBSC and BM groups, respectively. There was no difference between the 2 groups in bacteremia, cytomegalovirus reactivation or disease, and fungal infection. The 3-year transplant-related mortality (TRM) rates were 42% in the PBSC group and 31% in the BM controls (P ‫؍‬ .7) and the survival rates were 46% and 51%, respectively. The probability of relapse was 25% and 31% in both groups (NS), resulting in diseasefree survival rates of 43% in the PBSC group and 46% in the BM controls (NS). In the multivariate analysis, early disease, acute GVHD grade 0 to I, and presence of chronic GVHD were independent factors associated with a better disease-free survival in this study. PBSC from HLAcompatible unrelated donors can be used safely as an alternative to BM for stem cell transplantation. (Blood. 2001;98: 1739-1745)

Summary:Matched unrelated donor transplants have an increased risk of severe graft-versus-host disease and transplantrelated mortality (TRM). ATG has been introduced to decrease GvHD and to facilitate engraftment. We conducted a retrospective analysis of 333 patients with chronic myelogenous leukemia, who were treated with Fresenius ATG (n ¼ 145, average ¼ 90 mg/kg bw, range 40-90 mg/kg bw) or standard immunosuppression without ATG (n ¼ 188). Both groups were comparable regarding distribution of age, sex, HLA-matched vs mismatched donors. ATG Fresenius led to a faster leukocyte engraftment, decreased the incidence of acute GvHD and TRM (P ¼ 0.01 and P ¼ 0.03) and led to a significant better overall survival (70 vs 57%, P ¼ 0.03). We concluded that a prospective randomized study is needed to evaluate the definite role of ATG in hemopoietic stem cell transplantation.

Mycophenolate mofetil (MMF), a new immunosuppressive drug successfully used in renal and heart transplant recipients, was used in combination with cyclosporin A (CsA), methotrexate (MTX) and prednisolone for the prophylaxis of acute graft-versus-host disease (aGVHD) after bone marrow transplantation (BMT) and peripheral blood stem cell transplantation (PBSCT) from human leukocyte antigen (HLA)-mismatched, unrelated (n = 9) and related donors (n = 4) in an open single-centre phase II study. Thirteen patients, transplanted from HLA-mismatched donors of 18-57 yr of age, received 1 g MMF daily, starting at day 10, in addition to CsA and prednisolone for aGVHD prophylaxis. All patients were engrafted between days 13 and 15. Four of the 13 patients experienced aGVHD grade I/II (n = 2) and grade III (n = 2). All patients except 3 were alive on day 100 post-transplantation. No severe adverse effects of MMF were recorded. In our pilot study, we demonstrated that MMF can be used safely for the prophylaxis of aGVHD.