Usefulness of cytosine arabinoside (NSC-63878) and prednisone (NSC-10023) in refractory childhood lymphoblastic leukemia.

One hundred forty-three children with refractory lymphoblastic and undifferentiated leukemia (ALL/AUL) were treated with cytosine arabinoside (Ara-C) and prednisone (Pred). The dose and duration of Ara-C was escalated during induction depending on the response seen in the peripheral blood and/or bone marrow. For those achieving a remission, Ara-C was also used to determine its maintenance capabilities. Of the 143 children, 79 attained a clinical remission, 45 having a complete bone marrow remission and 34 having a partial remission. Maintenance of remission with twice weekly Ara-C was short and did not appear to depend on the amount of Ara-C given during induction. The major toxicity of Ara-C was myelosuppression.