Intermediate- and high-dose cytosine arabinoside therapy in acute refractory leukemia

Seven patients with refractory and/or relapsed acute leukemia were treated with intermediate- or high-dose cytosine arabinoside (ara-C). One patient obtained complete remission and two achieved partial remission. We advocate intermediate ara-C in combination with anthracyclines for the treatment of patients with refractory and/or relapsed acute leukemia, because the toxicity is less severe than that of high-dose ara-C and the therapeutic results are not inferior to those obtained with high-dose ara-C. Kinetic differences in leukemic cells should be considered in order to obtain the maximum effect in intermediate- and high-dose ara-C therapy.