Age and remission induction therapy for acute myeloid leukemia: An analysis of data from the Korean acute myeloid leukemia registry

Abstract

Objective: The clinical characteristics and therapeutic strategy in acute myeloid leukemia (AML) are influenced by patients' age. We evaluated the impact of age on remission induction therapy for AML.

Methods: We retrospectively analyzed 3,011 adult AML patients identified from a nationwide database between January 2007 and December 2011.

Results: Three hundred twenty-nine (10.9%) acute promyelocytic leukemia (APL) and 2,682 (89.1%) non-APL patients were analyzed. The median age was 51 years and 55% of patients were male. Six hundred twenty-three patients (21%) were at favorable risk, 1522 (51%) were at intermediate risk, and 743 (25%) were at poor risk. As the age increased, the proportion of those at favorable risk and who received induction chemotherapy decreased. After induction therapy, complete response (CR) was achieved in 81.5% (243/298) of APL and 62.4% (1,409/2,258) of non-APL patients; these rates decreased as the age increased, with an obvious decrement in those older than 60 years. The median overall survival of non-APL patients was 18.7 months, while that of APL patients was not reached, with a 75% five-year survival rate.

Conclusions: Age impacts both the biology and clinical outcomes of AML patients. Further studies should confirm the role of induction remission chemotherapy by age group.

Fig 1. Flow diagram.

APL: acute promyelocytic leukemia, AI: cytarabine plus idarubicin, AD: cytarabine plus daunorubicin.

Fig 2. Patients stratified by age group (A) and cytogenetic risk (B).

Fig 3. Proportions of patients who received remission induction chemotherapy (A) and who achieved complete remission (CR) (B) by age group (all patients); Acute promyelocytic leukemia (APL) patients (C) and non-APL patients (D) who received remission induction chemotherapy and who achieved CR by age group.

Fig 4. Overall survival (OS) of all patients (n = 3,011) according to age group (A) and cytogenetic risk (B).

Fig 5. Overall survival (OS) comparison of cytarabine plus idarubicin (n = 1,155) and cytarabine plus daunorubicin (n = 255) in all non–acute promyelocytic leukemia patients (A), those 60 years or younger (B), and those older than 60 years (C).

Fig 6. Overall survival (OS) comparison of cytarabine plus idarubicin and cytarabine plus daunorubicin (AD) by cytogenetic risk: Favorable risk (A), intermediate risk (B), and poor risk (C).