Results of Dana-Farber Cancer Institute Consortium protocols for children with newly diagnosed acute lymphoblastic leukemia (1981–1995)

The Dana-Farber Cancer Institute (DFCI) ALL consortium has been conducting clinical trials in childhood acute lymphoblastic leukemia (ALL) since 1981. The treatment backbone has included intensive, multi-agent remission induction, early intensification with weekly, high-dose asparaginase, cranial radiation for the majority of patients, frequent vincristine/ corticosteroid pulses during post-remission therapy, and for high-risk patients, doxorubicin during intensification. Between 1981 and 1995, 1255 children with newly diagnosed ALL were evaluated on four consecutive protocols: 81-01 (1981–1985), 85-01 (1985–1987), 87-01 (1987–1991) and 91-01 (1991–1995). The 5-year event-free survival (EFS) rates (± standard error) for all patients by protocol were as follows: 74 ± 3% (81-01), 78 ± 3% (85-01), 77 ± 2% (87-01) and 83 ± 2% (91-01). The 5-year EFS rates ranged from 78 to 85% for patients with B-progenitor phenotype retrospectively classified as NCI standard-risk, 63–82% for NCI high-risk B-progenitor patients, and 70–79% for patients with T cell phenotype. Results of randomized studies revealed that neither high-dose methotrexate during induction (protocol 87-01) nor high-dose 6-mercaptopurine during intensification (protocol 91-01) were associated with improvement in EFS compared with standard doses. Current studies continue to focus on improving efficacy while minimizing acute and late toxicities.