DOES TREATMENT WITH ARA-C IN LOW DOSAGE CAUSE DIFFERENTIATION OF LEUKEMIC-CELLS

Abstract

A series of 21 patients (5 refractory anemias with an excess of blasts in transformation and 16 acute leukemias) were treated with small doses of ARA-C [cytosine arabinoside] (10 mg/m2 per 12 h for 15-21 days). Improvement was noted in 15 cases (71%) and complete remission observed in 12 (57%). Complete remission was obtained after 1 course of treatment in 8 cases. The fact that these patients entered remission relatively slowly and did not suffer marrow aplasia suggests that low-dose ARA-C may function in vivo as it does in vitro, i.e., by inducing differentiation of leukemic blasts.