Intensive postremission chemotherapy in adults with acute myeloid leukemia

High dosages of cytarabine given as chemotherapy after remission of cancer prolonged the period of remission in patients with acute myeloid leukemia. A group of 596 patients aged over 16 who were in remission after primary chemotherapy treatment were randomly assigned to post-remission chemotherapy at one of three dosages of cytarabine: 100 mg, 400 mg, or 3000 mg. They were followed for an average of 52 months. Compared with the 100 mg dosage, patients receiving the 400 mg dosage were 25% more likely to survive free of disease and those receiving the 3000 mg dosage were 33% more likely to survive disease-free. After four years, 44% of the patients treated with 3000 mg dosages remained disease free. These results justify the high rate of serious side effects from cytarabine. However, patients older than 60 had no more than a 16% probability of disease-free survival whatever the dosage group. This age group also experienced unacceptable rates of neurologic side effects.