1. ¹Department of Medicine, Center for International Blood and Marrow Transplant Research, Medical College of Wisconsin, Milwaukee, WI, USA
2. ²Department of Pediatrics, Hematology, Oncology and Transplantation, Medical College of Wisconsin, Milwaukee, WI, USA
3. ³Statistical Center, The Children's Oncology Group, National Childhood Cancer Foundation, Arcadia, CA, USA
4. ⁴Department of Statistics, University of Florida, Gainsville, FL, USA
5. ⁵Department of Pediatrics, Hematology and Oncology, New York University Medical Center, New York, NY, USA
6. ⁶Department of Pediatrics, Hematology, Oncology and Stem Cell Transplantation, University of Miami Miller School of Medicine, Miami, FL, USA
7. ⁷Department of Hematology and Oncology, Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
8. ⁸Department of Pediatrics, Hematology and Oncology, Medical College of Virginia Hospital, Richmond, VA, USA
9. ⁹Department of Hematology and Oncology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
10. ¹⁰Department of Pediatrics, Southern Alberta Children's Cancer Center, Calgary, AB, Canada
11. ¹¹Department of Hematology and Oncology, Children's Hospital Medical Center, Cincinnati, OH, USA

Correspondence: Dr M Eapen, Center for International Blood and Marrow Transplant Research, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA. E-mail: meapen@mcw.edu

Received 30 August 2007; Revised 8 October 2007; Accepted 17 October 2007; Published online 22 November 2007.

Abstract

In children with acute lymphoblastic leukemia (ALL) with isolated central nervous system (CNS) relapse and a human leucocyte antigen (HLA)-matched sibling, the optimal treatment after attaining second remission is unknown. We compared outcomes in 149 patients enrolled on chemotherapy trials and 60 HLA-matched sibling transplants, treated in 1990–2000. All patients achieved a second complete remission. Groups were similar, except the chemotherapy recipients were younger at diagnosis, less likely to have T-cell ALL and had longer duration (18 months) first remission. To adjust for time-to-transplant bias, left-truncated Cox's regression models were constructed. Relapse rates were similar after chemotherapy and transplantation. In both treatment groups, relapse rates were higher in older children (11–17 years; RR 2.81, P=0.002) and shorter first remission (<18 months; RR 3.89, P<0.001). Treatment-related mortality rates were higher after transplantation (RR 4.28, P=0.001). The 8-year probabilities of leukemia-free survival adjusted for age and duration of first remission were similar after chemotherapy with irradiation and transplantation (66 and 58%, respectively). In the absence of an advantage for one treatment option over another, the data support use of either intensive chemotherapy with irradiation or HLA-matched sibling transplantation with total body irradiation containing conditioning regimen for children with ALL in second remission after an isolated CNS relapse.