1. ¹Department of Pediatrics, Hematology Oncology Division, University of Utah, Salt Lake City, UT, USA
2. ²Department of Clinical Sciences South Bristol, University of Bristol, Bristol, UK
3. ³National Blood Service, Southmead, Bristol, UK
4. ⁴Bone Marrow Transplantation Unit, Bristol Royal Hospital for Children, Bristol, UK

Correspondence: Dr Z Afify, Department of Pediatrics, Division of Pediatric Hematology Oncology, University of Utah, Primary Children's Medical Center, 100 N Medical Dr Suite 1400, Salt Lake City, UT 84113, USA. E-mail: pczafify@ihc.com

Received 13 August 2004; Accepted 1 February 2005; Published online 4 April 2005.

Abstract

Between July 1990 and March 2002, 35 consecutive children with ALL in third complete remission (CR3) underwent stem cell transplantation (SCT) from unrelated donors (UD). All patients received CAMPATH-1M 5–20 mg daily for 5 days. Grafts were T-cell depleted in 30 patients, 29 by CAMPATH antibodies and one by CD34 selection. Median follow-up was 3.8 years (0.3–9.3). Event-free survival (EFS) at 3 years was 35% (SE 8%); relapse rate and transplant-related mortality (TRM) at 3 years was 42 and 23%. Short first complete remission (CR1) <2.5 years was associated with lower EFS (P=0.001), higher TRM (P=0.019) and higher relapse rate (P=0.023). Short second complete remission (CR2) <2.5 years was associated with lower EFS (P=0.003) and higher TRM (0.009). Higher relapse rate and lower EFS were associated with isolated first extramedullary relapse (P=0.019, 0.012). There was no significant difference in outcome between mismatched unrelated donor stem cell transplantation (MMUD-SCT) and matched unrelated donor stem cell transplantation (UD-SCT). We conclude that UD-SCT is an effective treatment of ALL in CR3. The outcome remains limited by TRM and a high relapse rate. Short duration of CR1 and of CR2 and extramedullary site at first relapse are particularly adverse. MMUD should also be considered in high-risk patients, since the outcome of MMUD appears similar to MUD.