To determine the prognostic significance of the detection of the minimal residual disease (MRD) in children with AML1/ETO AML, we compared the results of reverse-transcription polymerase chain reaction (RT-PCR) and quantitative reverse-transcription polymerase chain reaction (RQ-PCR).
Between January 2006 and February 2013, 70 patients (≤16 years of age) with AML1/ETO AML were included in our study. Bone marrow samples were evaluated using by both RT-PCR and RQ-PCR assays. AML1/ETO transcripts were normalized to 105 ABL copies.
When treated with fewer than four courses of therapy, no association was found between positive RT-PCR results and relapse. After four courses of therapy, a positive RT-PCR result was correlated with a probability of relapse. After induction chemotherapy, a >1.8 log reduction in AML1/ETO transcripts in BM determined by RQ-PCR may represent a subgroup of patients at low risk for relapse. MRD levels after consolidation (Courses 2 and 3) were also informative.
Both RT-PCR and RQ-PCR can be used to detect MRD in childhood AML1/ETO AML. RQ-PCR can identify patients who are at high risk of relapse earlier than can RT-PCR. Pediatr Blood Cancer 2014; 61:1761–1766. © 2014 Wiley Periodicals, Inc.