[Acute lymphoblastic leukemia in children. Long survivals obtained with protocols C2-72 and D-74 (1972-1977)].

Between 1972-1977, 92 patients with acute lymphoblastic leukemia, between 0 and 14 years of age, were treated with C2-72 and D-74 protocols. Induction treatment consisted of prednisolone (PRED)-vincristine (VCR) with the addition of daunorubicin (prot. C2-72) or asparaginase (prot. D-74). In both protocols, preventive therapy on the CNS consisted of cranial irradiation (24 Gy) and 5 doses of methotrexate i.t. (MTX). For the maintenance phase in protocol C2-72, three combinations: mercaptopurine (MP)-MTX, MP-Ara.C and MTX-cyclophosphamide, were sequentially administered for 3 years, with reinductions of PRED-VCR every three months. In protocol D-74, only MP-MTX was used for 3 years; the random half of the patients also received "reinductions". In protocol C2-72, BCG was administered by scarifications for 2 years to patients in remission after 36 months; in D-74, the random-half patients received BCG and irradiated allogeneic blasts for one year. The other half of the patients received no other treatment. The overall disease-free survival rate is 45.6% with a duration of between 84 and 156 months. Only one death occurred after 7 years. In protocol C2-72, 9 of 26 initial patients (34.6%) and in protocol D-74, 33 of 66 initial patients (50%) are still alive, off treatment and with no sign of disease. Ten patients (10.8%) died in continuous remission of infection (8) or toxic encephalopathy (2); five deaths were caused by "Pn. carinii". The incidence of meningeal relapse was 11% and isolated testicular relapse in males 15.7%; moreover, in 6 of the 22 boys in remission, programmed testicular biopsy showed interstitial leukemic infiltrates. Analysis of initial risk factors permitted the establishment of a risk index (r.i.): in cases with a r.i. below 3 (76% of cases) the survival rate was 53%; in the group with a higher r.i. (24%), it was 22%. Further conclusions of this study were: the lack of effectivity of "reinductions" and immunotherapy and proof of a higher rate of relapses in males mainly owing to isolated testicular relapse.