Risk assessment before allogeneic hematopoietic cell transplantation for older adults with acute myeloid leukemia

Abstract

Acute myeloid leukemia (AML) most commonly affects patients older than 60 years. Outcomes of treatment of older AML patients have been poor. The advent of reduced-intensity conditioning (RIC) regimens made allogeneic hematopoietic cell transplantation (HCT) an available treatment option with curative intent for older AML patients. Because older patients are often excluded from clinical trials, little is known about the stratification of their risks before allogeneic HCT. While recent studies of RIC and allogeneic HCT have shown little impact of age on outcomes, other variables such as the recipient health status and the AML disease status and chromosomal aberrations have proven to be of prognostic significance. Here, the authors review recent studies of allogeneic HCT for older patients with AML with detailed evaluation of risk factors for relapse as well as non-relapse mortality. The authors have integrated the currently available information on transplant risks into a five-category risk–benefit system that could aid in the decision-making in this patient population.

Keywords::

• acute myeloid leukemia
• age
• allogeneic hematopoietic cell transplantation
• chromosome aberrations
• comorbidity
• risk assessment

Financial & competing interests disclosure

The authors have no conflict of interest information to disclose. This work has been supported by grants CA18029 and HL088021 from the National Institute of Health. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• • Acute myeloid leukemia (AML) is a disease of the older population with a median age at diagnosis of 68 years. Unfortunately, the outcomes of older AML patients remain poor.

• • Chronological age, per se, between 60 and 75 years does not seem to be a barrier to reduced-intensity conditioning (RIC) and allogeneic hematopoietic cell transplantation (HCT). However, the criteria for selection of older patients with AML to be eligible for allogeneic HCT have not been well studied.

• • Health status measures particularly comorbidity indices such as the HCT-CI, and performance status scales independently and strongly impact risks for non-relapse mortality (NRM) after allogeneic HCT. Both measures should be assessed before HCT for stratification of risks for NRM.

• • Patient and physician preferences and their perceptions of chances for cure might bias selection for HCT candidacy. These factors together with race and socioeconomic features should be more appropriately addressed in future studies.

• • First or second complete remission (CR) at time of HCT and having more favorable cytogenetic abnormalities signifies better outcomes after allogeneic HCT for older AML patients.

• • Novel chromosomal abnormalities or genetic markers should be incorporated in future clinical trials to further improve risk–benefit ratio assessments before allogeneic HCT.

• • RIC regimens followed by allogeneic HCT resulted in better survivals among older patient when compared, mostly retrospectively, with either autologous HCT or conventional chemotherapy.

• • Grafts from HLA-identical siblings continue to be associated with the most favorable outcomes after allogeneic HCT. Acceptable outcomes have been reported using alternative donor grafts.