Chemotherapy for bone marrow relapse of childhood acute lymphoblastic leukemia.

Results of the BMF study group trials ALL-REZ 83 and 85 for relapsed acute lymphoblastic leukemia (ALL) are presented. For children with late marrow relapse, remission rates of about 90% were seen in both studies. In children treated for early marrow relapse, the remission rate in study ALL-REZ 85 was superior (86% vs 62%). The probability of event-free survival for all patients and for those with early marrow relapse was also statistically significant (P less than 0.05). Children with T-cell ALL had an extremely unfavourable prognosis in both studies.