In 2003, the Europe Against Cancer (EAC) program established RT‐qPCR standardization and quality control analysis for the PML‐RARα FG transcript and recommended the ratio of FG copy number to control genes (CG) copy number (FGCN/CGCN) as the PML‐RARα FG transcript level.14, 15 The MRD value is a ratio between the FG transcript level in follow‐up ((FGCN/CGCN)FUP) and diagnostic samples ((FGCN/CGCN)DX).14, 15 These studies promoted the improvement of the PCR detection sensitivity and accuracy for PML‐RARα FG, especially the EAC‐sanctioned RT‐qPCR. Here, PML is linked to cancer.