Journal of Clinical Oncology, Vol 1, 308-316, Copyright © 1983 by American Society of Clinical Oncology
Randomized study of 3 years versus 5 years of chemotherapy in childhood acute lymphoblastic leukemia
ME Nesbit Jr, HN Sather, LL Robison, JA Ortega and GD Hammond
Between 1972 and 1975 the Children's Cancer Study Group conducted two
clinical trials for the treatment of newly diagnosed patients with acute
lymphoblastic leukemia. Upon achieving 3 yr of continuous complete
remission, 316 children and young adults were randomly allocated either to
discontinue chemotherapy or to continue chemotherapy for an additional 24
mo. With a median follow-up from the time of randomization of 50 mo, those
patients who received 3 yr of therapy have demonstrated a statistically
non-significant yet higher incidence of bone marrow relapse as compared to
those patients treated for 5 yr (p = 0.09). However, the proportion of
patients surviving 5 yr from randomization is 93% for the 3-yr treatment
group and 89% for the 5-yr treatment group (p = 0.27). No significant
difference was observed between the randomized groups for the occurrence of
testicular relapse (p = 0.12), central nervous system relapse (p = 0.17),
or first occurrence of relapse or death (p = 0.24). The relapse-free
survival of patients treated for 5 yr as compared to those treated for 3 yr
was not significantly higher in males (81% versus 75%, p = 0.14) or females
(89% versus 89%, p = 0.95). This randomized study did not demonstrate a
significant difference between treatment for either 3 or 5 yr.
