1. ¹Institute of Hematology and Clinical Oncology 'L e A. Seràgnoli', University of Bologna, St Orsola Hospital, Bologna, Italy
2. ²Tissue Typing Regional Reference Center, St Orsola Hospital, Bologna, Italy
3. ³Stem Cell Transplant Program, Section of Hematology/Oncology, University of Illinois at Chicago, Chicago, IL, USA

Correspondence: Dr F Bonifazi, Institute of Hematology and Clinical Oncology 'L eA Seràgnoli', University of Bologna, St Orsola-Malpighi Hospital, via Massarenti 9, 40138 Bologna, Italy

Received 13 January 2003; Accepted 18 March 2003.

Abstract

Antithymocyte globulin (ATG) treatment prevents graft failure and results in a low incidence of GVHD, but an increased risk of relapse could be expected as a consequence of reduced GVHD. From September 1995 to June 2001, 28 consecutive chronic myeloid leukemia (CML) patients underwent unrelated bone marrow transplants: 21 were in chronic phase (CP) and seven in advanced phase (AP). Median age was 35.5 years (range 20–50). HLA typing was based on high-resolution molecular techniques; in eight cases there were one or more allele mismatches. The preparative regimen consisted of TBI, EDX 120 mg/kg and rabbit ATG 15 mg/kg. All patients engrafted and no rejection occurred. Acute GVHD grade III–IV occurred in six patients (21%). Chronic GVHD occurred in 10 (40%) and it was extensive in one. Four out of seven patients transplanted in AP had a hematological relapse. Of 21 in CP, there was one cytogenetic and one molecular relapse: these two patients are now in complete remission with imatinib mesylate. With a median follow-up of 45.7 months, the 5-year survival is 76.2% for those transplanted in CP. These data demonstrate that transplants performed in CP, with low-dose ATG, are associated with a good outcome, low incidence of GVHD and no increase of relapse.