Medical Research Council leukaemia trial, UKALL VII. A report to the Council by the Working Party on Leukaemia in Childhood.

Eighty two eligible children with 'standard risk' lymphoblastic leukaemia were entered into the Medical Research Council UKALL VII trial. Three failed to remit. With a minimum follow up time of four years, actuarial relapse free survival for the remainder was 65%; a significant improvement over the two preceding 'standard risk' trials at the same stage. Only one of five treatment variables possibly affected relapse free survival; this being whether methotrexate was given orally or parenterally during remission maintenance treatment. Twenty seven of 36 patients (75%) who were given intramuscular methotrexate remain alive and in their first remission compared with 23 of 41 (56%) given the drug orally. Although statistically significant differences in small trials should be interpreted with caution, this finding raises the possibility that orally administered methotrexate is not completely absorbed.