New strategies for the evaluation of the nadir bone marrow following induction in acute myeloid leukemia.

PURPOSE OF REVIEW

Patients with acute myeloid leukemia (AML) routinely undergo a bone marrow biopsy 7-10 days after induction chemotherapy to evaluate treatment effectiveness. Measuring blast count by morphology alone has been the standard hematopathologic technique. Although helpful to guide future treatment decisions, the early bone marrow does not predict well which patients will achieve complete remission, and ultimately be cured. New methods of assessing early treatment effectiveness are being developed. This review summarizes the current utility of early bone marrow evaluations and looks toward future developments.

RECENT FINDINGS

More sensitive techniques than light microscopy are available to analyze the presence or absence of leukemia after treatment. These include flow-cytometry and polymerase chain reaction-based assays, and their use is playing a larger role in monitoring therapy effectiveness after induction and during consolidation. Importantly, novel techniques including enzymatic amplification staining (performed on bone marrow samples) and noninvasive molecular imaging have been studied and may play a role in future therapy asessment.

SUMMARY

Identifying and implementing new tools to measure therapy effectiveness will be an important component of improving outcomes for patients with AML.