Matsuo H, et al. - This trial encompassed the monitoring of fusion gene transcripts in order to speculate the relapses in pediatric acute myeloid leukemia. The promising marker of relapse was discovered to be the detection of MLL-AF9 transcripts by RQ-PCR. On the other hand, limitation prevailed in the clinical utility of detecting AML1-ETO and CBFB-MYH11 expression. However, a higher AML1-ETO expression could serve as a potential predictor of relapse when evaluated based on an optimal threshold.