[Acute lymphoblastic leukemias off therapy: course of 80 cases after treatment cessation]

To retrospectively analyse all the patients diagnosed and treated in the same hospital for acute lymphoblastic leukaemia (ALL) in whom therapy was suppressed after sustained complete remission (CR) for a variable period.

Eighty cases of ALL treated at the Jiménez Díaz Foundation between 1968 and 1991 were revised. Treatment had been suppressed after 60 months of maintained CR (1968-1974) or after 28 months (1986-1991), with a median follow-up after suppression of 6 years. All the patients had been treated with several protocols (FJD-68, FJD/BFM, APO, BFM-83, BFM-86 and BFM-90). Maintained CR, relapses and course after therapy cessation were analysed. Actuarial curves of RC duration and survival were drawn according to the Cutler and Ederer life tables.

The age at diagnosis ranged from 1.5 to 68 years. Childhood (< 15 years) ALL presented in 49 cases; 25 were young adults (15-30 years), and 6 others were over 30 years of age. Two of the 80 patients (2.5%) died in CR (astrocytoma and demyelinating leukoencephalopathy). Fifty-eight patients (72.5%) are living in maintained CR; 20 others relapsed (25%), 14 of them (70%) attaining a second CR. Allogenic BMT was carried out in 4 such cases. Four patients are out of any treatment after the second CR. The actuarial curves of CR duration after suppression of therapy gave a stable plateau at 73% for children, at 75% for young adults and at 22% for patients over 30 years. The survival after suppression of therapy showed a plateau at 75% for children and at 86% for young adults.

1) Relapse was seen in 25% of the patients after cessation of therapy. 2) Relapse occurred in the first two years after therapy cessation in 75% of the instances. 3) At this writing, 78.7% of the patients keep up the CR. 4) Adults over 30 years of age comprise the poorest prognosis. 5) The course of young adults in this series after cessation of therapy is as good as that of children.