PURPOSE Late abnormalities of left ventricular (LV) performance occur in most survivors of childhood acute lymphoblastic leukemia (ALL) treated with moderate anthracycline doses. We studied the prevalence of late cardiotoxicity in patients treated with lower anthracycline doses and related this to survival. PATIENTS AND METHODS Echocardiograms were performed in 50 normal children and 120 relapse-free ALL survivors 6.2 +/- 2.0 years after the end of cumulative daunorubicin doses of 90 mg/m2 (n = 40), 180 mg/m2 (n = 40), or 270 mg/m2 (n = 40) on UKALL X pilot (1982 to 1984) or UKALL X (1985 to 1989) protocols. Age at treatment onset was 4.7 +/- 2.8 years. Cardiac abnormalities were reviewed in light of the UKALL X 5-year disease-free survival rates of 57% (95% confidence interval [CI], 51% to 63%), 61% to 62% (95% CI, 56% to 68%), and 71% (95% CI, 66% to 76%) for the groups that received 90, 180, and 270 mg/m2 of daunorubicin, respectively. RESULTS ALL survivors had reduced LV fractional shortening (FS) compared with normal (32.3% +/- 4.4% v 35.9% +/- 4.2%, P < .005), which was accounted for by increased LV end-systolic stress (49.4 +/- 13.5 v 42.2 +/- 9.1 g/cm2, P < .001), whereas LV contractility independent of loading conditions was normal for the group as a whole. Of 27 patients (23%) with cardiac abnormalities, 25 (21%) had increased end-systolic stress, whereas only two (2%) had reduced contractility. The proportion with cardiac abnormality was similar in the three dose groups. Anthracycline dose, age at treatment, sex, follow-up duration, growth hormone, pubertal status, hemoglobin level, and total WBC count at presentation were not predictive of increased LV end-systolic stress. CONCLUSION There was a reduced incidence and severity of cardiac abnormalities with the lower anthracycline dose protocols (90 to 270 mg/m2) studied compared with previous reports in which subjects had received moderate anthracycline doses (approximately 300 to 550 mg/m2). Cumulative anthracycline dose within the range 90 to 270 mg/m2 did not relate to cardiac abnormalities. This suggests that there may be no safe anthracycline dose to avoid late cardiotoxicity, but reinforces the use of the protocol that affords best survival within the dose range studied.
The outcome in children with acute leukaemia with (n = 90) and without Down9s syndrome (n = 4377) was compared. Sixty three (70%) of those with Down9s syndrome had acute lymphoblastic leukaemia and in comparison with 3664 (84%) controls had similar prognostic features except for a significant excess of the 9common9 immunological subtype of acute lymphoblastic leukaemia. The outcome of the children with Down9s syndrome was significantly worse with a five year overall actuarial survival of 28% compared with 59% in the control group. It appeared that both suboptimal chemotherapy and a high rate of infective problems contributed to the poor survival. Twenty six children with Down9s syndrome had acute myeloblastic leukaemia and were significantly younger and had a higher percentage of the megakaryocytic and erythroid subtypes of acute myeloblastic leukaemia than the 713 controls. The outcome was similar in the two groups. It is concluded that the patients with Down9s syndrome who develop acute leukaemia should receive standard protocols without modification, but aggressive supportive care is necessary to improve outcome.
In 22 boys among a group of 169 with acute lymphoblastic leukaemia the first relapse occurred in the testis. In 14 of these late isolated testicular relapse was detected on routine biopsy or became apparent after treatment was electively stopped. Eleven of these boys were treated with reinduction, irradiation of 2400 rads to both testicles, intrathecal methotrexate, and two years of chemotherapy; 10 remained well and were in second complete remission from two and a half to five and a half years later. It is concluded that boys with late isolated testicular relapse fare better than those with late marrow relapse and may have a change of long-term disease-free survival.
The relationship between the prescribed dose of drugs during continuing (maintenance) therapy, the degree of marrow suppression caused, and subsequent event‐free survival was examined in a cohort of 740 children with lymphoblastic leukaemia treated on MRC UKALL X. Girls, younger children, and patients who had received intensification treatment, were prescribed lower doses of mercaptopurine, became neutropenic more readily, and had more interruptions of treatment. Children who had one or more episodes of neutropenia with a count of < 0.5 × 10 9 /l had a better prognosis than those who never became neutropenic. We conclude that early intensification treatment influences the probability of neutropenia during continuing treatment and that patients exhibiting myelosuppression during this phase of treatment have a better chance of prolonged remission.