In acute myeloid leukemia (AML), molecular diagnosis for the optimal management of patients and for minimal residual disease (MRD) monitoring is of extreme importance. Cumulative data suggest that quantitative monitoring or MRD in AML with fusion transcripts corresponding to 5(I;21), inv(16), and t(15;17) is useful in distinguishing patients at high risk of relapse from those in durable remission. Real-time quantitative polymerase chain reaction (RQPCR) is by far the most sensitive assay in the context of MRD detection. We present herein an overview of the principles of RQ-PCR encompassing both the chemistries (double-stranded DNA detection or specific fragment detection) and the instruments. The absolute and relative quantification and the most commonly used methods for calculation of MRD results in absolute quantification are also described.
