prognostic indicator and determinate of risk-adapted therapy. The advent of molecular technologies such as PCR, single-nucleotide polymorphism analysis, and gene expression is allowing a more sensitive and specific method to monitor and study ALL. It is imperative that the APN and nurse become known-ledgeble of this quickly evolving technology as it is translated from the laboratory to clinical practice. The nurse should understand that this technology is of such sensitivity and specificity that molecular techniques are quickly replacing the traditional bone marrow morphological examination for the documentation of pre-B-cell leukemia disease response, therefore, decreasing the number if invasive procedures during the course of therapy. However, if the MRD is not ≤0.01% at the end of induction, the nurse should be knowledgeable in educating the child and parent regarding heightened surveillance (molecular and morphological studies); rationale for intensified therapy; and if MRD persists or increases, the need for bone marrow transplant.