ALLOGENEIC BONE-MARROW TRANSPLANTATION FOR HIGH-RISK ACUTE LYMPHOBLASTIC-LEUKEMIA IN FIRST REMISSION - LONG-TERM RESULTS FOR 42 PATIENTS CONDITIONED WITH AN INTENSIFIED REGIMEN (TBI, HIGH-DOSE ARA-C AND MELPHALAN)

Attempts to improve the efficacy of pretransplant conditioning regimen s have been published, the potential of a better antileukemic effect b eing impaired by more frequent and severe toxicities, The efficacy of an intensified regimen, TAM (TBI, high-dose cytosine arabinoside and m elphalan), is evaluated by analysing long-term follow-up of a homogeno us group of 42 high-risk ALL patients allografted in first CR, Age at time of BMT was 25.9 +/- 10.4 years (3-41), Twenty-two patients had mo re than three adverse prognostic factors, Ten patients had a Ph chromo some, Probability of overall survival was 45 +/- 9%, and for all survi ving patients median followup time was 66 months, Event-free survival was 40 +/- 8% at 7 years after transplantation and the expected relaps e rate reached 31%, Twenty-two deaths occurred, six after a relapse bu t 16 appeared to be directly due to the BMT procedure, None of the pre transplant characteristics significantly affected outcome after BMT. T AM appeared to be an efficient antileukemic therapy for conditioning h igh-risk ALL patients before allogeneic transplantation, but was still very toxic, The use of TAM in adult ALL patients in first CR is not r ecommended and the real role of intensified conditioning regimens rema ins to be demonstrated.