Effect of Age on Treatment Decision-Making in Elderly Patients With Acute Myeloid Leukemia

Patients aged ≥70 years with acute myeloid leukemia (AML) have a poorer prognosis than those aged 60 to 69 years. The poor outcome is the result of treatment-related toxicity in elderly patients, owing to comorbidities, the greater possibility of other hematopoietic disorders, and a biologically poor risk prognosis. Anthracycline- and cytarabine-based therapy, administered for 3 and 7 days respectively (3 +7), remains the standard induction therapy for this patient population. This approach improved survival compared with supportive care (median, 5 vs. 3 months) for adults aged ≥ 65 years. However, the overall view has been that the results of intensive chemotherapy in elderly patients remain poor. Although complete remission (CR) rates of 40% to 80% can be achieved in highly selected populations, long-term survival has been poor. Furthermore, most clinical trials have only enrolled patients with an adequate performance status (PS).

Prognostic models have been developed from clinical trial data to predict the outcomes for older patients. However; each model relies on chronologic age. Age is a surrogate measure for both changes in tumor biology and patient characteristics. Understanding which patients are likely to benefit from intensive therapies versus low-intensity therapies or supportive care is critical. The definition of "fit" to undergo intensive induction therapy has not been established, and the therapeutic choice is mainly determined by physician and patient decision. In older patients, low-dose cytarabine (LD-AraC) has been demonstrated to be more beneficial than best supportive care and hydroxyurea. The recent availability of new drugs that could have an improved side effect profile and, in some cases, bioavailability might offer future improvement for this patient population. In this setting, the investigators have tended to consider, since 2007, patients aged ≥70 years as potential candidates for alternative lower intensity therapy (LD-AraC, hypomethylating agents) even when they presented in good physical condition.

The investigators goal was to determine whether age ≥ 70 years could represent a useful and simple cut off for treatment decision-making in clinical practice and whether low-intensity therapy could be an alternative therapeutic approach to intensive chemotherapy even for patients aged ≥ 70 years who were theoretically "fit" (WHO /ECOG/ PS of ≤ 2).