Trials and Tribulations in the Frontline Treatment of Older Adults with Acute Myeloid Leukemia

Abstract

Acute myeloid leukemia (AML) is a heterogeneous aggressive hematologic malignancy derived from malignant clones that promote their own growth and survival at the expense of normal hematopoiesis resulting in life-threatening bleeding and infections. Traditional initial AML therapy has been centered on a backbone of intensive chemotherapy often composed of an anthracycline and cytarabine. This strategy has proven most effective in patients less than 60 years of age due to both patient-related tolerability factors as well as changes in AML biology centered on chemotherapy refractory mutational profiles that are seen with advancing age. Recent improvements in frontline AML therapy have been seen in patients 60 years of age and over, a population most typically referred to as “older” adult AML. Herein, we describe the characteristics of “older” adult AML, review the differences in outcomes amongst those 60–75 and those over 75 years of age, and cite challenges in delivering frontline therapies within this group based not only on therapeutic toxicity but also on the patient’s overall level of “fitness” and inherent biology. We also discuss the role of targeted therapies that inhibit specific mutations and have the potential to deliver improved efficacy with less side effects while also recognizing that some selected older AML patients still benefit from intensive induction therapy.