Peripheral blood blast clearance during induction therapy in acute myeloid leukemia.

Although several parameters are useful for risk stratification of patients with acute myeloid leukaemia (AML), there are no firm criteria for predicting response to induction treatment of individual patients. Daily flow cytometry (FC) analysis, carried out during induction treatment in 61 AML patients,showed that the clearance of blasts from peripheral blood (PBC) correlated closely with response, as assessed by bone marrow FC on day 14, and by morphologic analysis at haematopoietic recovery. Therefore, a major treatment outcome can be predicted very early in AML patients, thus providing an opportunity for tailoring treatment modalities from the outset.