Intensive chemotherapy does not benefit most older patients (age 70 years or older) with acute myeloid leukemia

Patients ≥ 70 years of age with acute myeloid leukemia (AML) have a poor prognosis. Recent studies suggested that intensive AML-type therapy is tolerated and may benefit most. We analyzed 446 patients ≥ 70 years of age with AML (≥ 20% blasts) treated with cytarabine-based intensive chemotherapy between 1990 and 2008 to identify risk groups for high induction (8-week) mortality. Excluding patients with favorable karyotypes, the overall complete response rate was 45%, 4-week mortality was 26%, and 8-week mortality was 36%. The median survival was 4.6 months, and the 1-year survival rate was 28%. Survival was similar among patients treated before 2000 and since 2000. A multivariate analysis of prognostic factors for 8-week mortality identified the following to be independently adverse: age ≥ 80 years, complex karyotypes, (≥ 3 abnormalities), poor performance (2-4 Eastern Cooperative Oncology Group), and elevated creatinine > 1.3 mg/dL. Patients with none (28%), 1 (40%), 2 (23%), or ≥ 3 factors (9%) had estimated 8-week mortality rates of 16%, 31%, 55%, and 71% respectively. The 8-week mortality model also predicted for differences in complete response and survival rates. In summary, the prognosis of most patients (72%) ≥ 70 years of age with AML is poor with intensive chemotherapy (8-week mortality ≥ 30%; median survival < 6 months).