Postremission therapy with two different dose regimens of cytarabine in adults with acute myelogenous leukemia.
Sixty-seven out of 105 (64%) adults with de novo acute myelogenous leukemia (AML), achieving complete remission after induction chemotherapy, entered two successive postremission treatment protocols. Between 1987 and 1989, 35 patients received an intermediate dose of cytarabine (IDAC) along with other drugs. Between 1990 and 1993, 32 patients received high dose cytarabine (HIDAC) with similar other drugs. Patients treated with IDAC had a median survival of 13.8 months (95% CI 11.2-23.1 months) and a 2 year survival of 34.3 +/- 8.0%. Patients receiving HIDAC had a median survival of 35.5 months (95% CI, lower limit 29.8 months) and a 2 year survival of 71.6 +/- 9.4% (P < 0.002). The 2 year actuarial leukemia-free survival (LFS) was 17.8 +/- 6.6% in the IDAC group and 67.3 +/- 10.0% months in the HIDAC group (P = 0.004). The HIDAC group had a significant 2 year survival advantage over the IDAC group only in patients younger than 45 years. The 2 year survival in the first group was 83.3 +/- 10.8% versus 23.5 +/- 10.3% in the IDAC group (P = 0.0001). In patients older than 45 years, no significant differences in 2 year survival was noticed (52.9 +/- 15.78 versus 44.4 +/- 11.7, P = 0.8). Censoring the 21 patients who underwent bone marrow transplantation (BMT) at BMT did not change significantly the survival analysis of the patients in each group. This study is consistent with previous reports favoring HIDAC intensification in the postremission treatment of young patients with AML.