High-dose cytosine arabinoside intensification for acute nonlymphocytic leukemia in patients over 56 years of age.

One hundred and nine consecutive patients with de novo acute nonlymphocytic leukemia aged over 56 years were admitted with the intention of administering high-dose cytosine arabinoside (HD Ara-C) intensification. After remission induction, the patients were consolidated with a course of daunorubicin (30 mg/m2/day, days 1-3) and Ara-C (100 mg/m2/day, days 1-7), followed by the intensification (Ara-C, 2 g/m2/12 h, days 1-4). The planned induction course was not started in 13 patients because of cardiac failure or unsatisfactory general status. Remission was achieved in 55% (53/96) of the patients. Twenty-seven patients (28%) had refractory disease, seven died early during induction therapy, five died of hemorrhage and three of infection during the hypoplasia that followed induction treatment. Thirty-nine patients started consolidation and 32 had the planned intensification. In these last patients the 3-year leukemia-free survival (LFS) probability was 29% (SE, 8%). No patient died as a consequence of intensification. The relapse rate of the intensified patients did not differ from the relapse rate of those patients who did not receive the planned intensification (p = 0.12). The only pretreatment variables significantly associated with a better LFS were younger age (p = 0.02) and a low WBC at diagnosis (p = 0.04). For the whole patient group, the 3-year survival probability was 15% (SE, 4%). This study shows that elderly patients can tolerate HD Ara-C. The patients completing consolidation-intensification have a currently acceptable LFS. To what extent HD Ara-C contributed to the length of the remissions remains unclear.