Further retrospective analyses of 205 APL and 629 non-APL AML patients from different hematology centers showed that either the CD64dim and homoCD13+homo CD33+homoMPO+ (myeloperoxidase) CD11c− panel or the CD64dim and homoCD13+homo CD33+homoMPO+ CD11c+CD10−CD117+ SSChigh (high side scatter signal) panel could distinguish APL from non-APL AML patients with nearly 100% sensitivity, specificity and accuracy. This evidence concerns the gene CD33 and acute myeloid leukemia.