Summary:From January 1984 to December 1994, ABMT was performed on 154 children (101 males, 53 females; median age 10, range 3-21 years) with ALL and registered for BMT by the AIEOP (Italian Association of Paediatric Haemato-Oncology). All patients were in CR: 98 were in 2nd CR and 56 were in Ͼ2nd CR. Fifteen children (9.7%) died of transplant-related mortality. Ninety-five patients (61.6%) relapsed at a median of 5 (range 1-42) months after ABMT. The 8-year EFS according to pre-BMT status was 34.6% (s.e. 4.9) for 2nd CR patients and 10.6% (s.e. 5.6) for patients in Ͼ2nd CR. By univariate analysis, site of relapse (isolated extramedullary (IE) vs BM: EFS = 68.5% vs 18.2%; P Ͻ 0.0001) and TBI containing regimen (TBI vs no TBI: EFS = 48.1 vs 15.4%; P = 0.0023) were significant factors for 2nd CR patients. When the 2nd CR subset with BM involvement was analysed, TBI became insignificant (EFS = 25.4 vs 11.8%). No factors influenced EFS in patients in Ͼ2nd CR. By multivariate analysis, site of relapse was the only significant factor in 2nd CR patients (P Ͻ 0.0001). In conclusion, ABMT is an effective treatment after one early IE relapse. Few patients can be rescued after BM relapse. Keywords: childhood ALL; ABMT; BM relapse; isolated extramedullary relapse The introduction of intensive front-line therapy has improved the EFS for childhood ALL.1-3 Nevertheless, approximately 25% of children who achieve CR relapse in the BM or in extramedullary sites. After a BM relapse, in spite of aggressive second-line therapy, only 20-50% of cases survive long term at 4-6 years. relapse, most children develop BM relapse or refractory CNS leukemia. 7-11 After a testicular relapse, the reported 3-year EFS with conventional retreatment depends on the time of relapse: 20% for patients relapsing on therapy, 12,13 40% for patients relapsing during the first year after stopping therapy, 13,14 and 100% for patients who relapse later.
13Following a 2nd relapse, the likelihood of prolonged EFS is further diminished. Allogeneic BMT, from an HLAidentical sibling [15][16][17] or unrelated donor, 18 seems to be the treatment of choice following an early BM relapse. Unfortunately, only 25-30% of children has a family donor and it is not always possible to find a fully compatible or minor mismatched unrelated donor despite the increased size of bone marrow donor panels. The role of BMT after an early isolated extramedullary (IE) relapse is less clear. 19,20 In order to investigate whether ABMT could represent an alternative option for children lacking an HLA-identical donor, 21-23 we retrospectively analysed 154 ALL patients who underwent ABMT with varying remission status.
Patients and methodsFrom January 1984 to December 1994, 154 ALL children in 2nd or subsequent CR underwent ABMT at 10 Italian paediatric BMT centres. The relevant data were collected by the AIEOP-BMT Registry via oriented reporting forms completed by the physician in charge at each BMT Centre. The front-line treatment was according to the AIEOP protocols of the 82, 85, 87, 88 se...