Bone marrow transplantation versus chemotherapy in the treatment of very high-risk childhood acute lymphoblastic leukemia in first remission: resultsfrom Medical Research Council UKALL X and XI

The role of bone marrow transplantation (BMT) in first remission of childre n with high-risk acute lymphoblastic leukemia (ALL) remains unclear. There were 3676 patients (aged 1 to 15 years) entered into the United Kingdom (UK ) Medical Research Council (MRC) trials UKALL X and XI from 1985 to 1997. O f these patients, 473 patients (13%) were classified as very high (VH) risk and were eligible for a transplantation from a matched histocompatible sib ling donor (MSD). We tissue-typed 286 patients; 99 patients had a matched r elated donor, and 76 patients received transplantations. Additionally, 25 c hildren received transplantations from a matched unrelated donor (MUD) desp ite trial guidelines for MSD transplantations only. The median time to tran splantation was 5 months (range, 2 to 19 months), and the median follow-up was 8 years. The 10-year event-free survival (EFS) adjusted for the time to transplantation, diagnostic white blood cell (WBC) count, Ph chromosome st atus, and ploidy was 6.0% higher (95% confidence interval (CI), -10.5% to 2 2.5%) for 101 patients who received a first-remission transplantation (MSD and MUD) than for the 351 patients treated with chemotherapy (transplantati on, 45.3%, vs chemotherapy, 39.3%). The transplantation group had fewer rel apses (31%) compared to relapses in the chemotherapy group (55%); however, the transplantation group had more remission deaths (18%) compared to remis sion deaths in the chemotherapy group (3%). In contrast the adjusted 10-yea r EFS was 10.7% higher (95% CI, -2.6% to 24.0%) for patients without a huma n leukocyte antigen (HLA)-matched donor than for those patients with a dono r (no donor, 50.4%, vs donor, 39.7%). In conclusion, for the majority of ch ildren with VH-risk ALL, the first-remission transplantation has not improv ed EFS. (Blood. 2000;96:2412-2418) (C) 2000 by The American Society of Hema tology.