Molecular diagnosis and monitoring of acute myeloid leukemia.

This concise review focuses on the new possibilities offered by molecular biology for the accurate diagnosis of chromosome abnormalities characteristic of some acute myeloid leukemias. Translocations t(8;21), t(15;17) and inv(16) may account for up to 30% of all cases of adult and childhood AML and their identification either by cytogenetics or molecular techniques is becoming of crucial importance for the routine diagnosis and treatment of AML, since they allow the identification of patients whose likelihood of cure is remarkably better. In these patients, the need of myeloablative protocols, supported by autologous or allogeneic transplantation, may not be required at least in first remission, and this can prevent the delivery of inappropriately toxic therapies. On the other hand, patients whose blasts are showing rearrangements of 11q23 band had a significantly worse prognosis and its precise identification may help the accrual to more appropriate and aggressive therapeutic protocols. These molecular markers are offering new tools, which are extremely sensitive, for the detection of minimal residual disease (MRD) for a growing number of AML patients. Although very promising in acute promyelocytic leukemia, the clinical significance and utility to investigate MRD persistence may be different for other the AML subgroups and caution should be taken in transferring these data to the clinical practice outside prospective controlled clinical trials.