Among the CD56-positive leukemic populations (n = 18, 9.1%), this marker was mostly heterogeneously expressed (n = 14) (Table 2), and only four samples demonstrated high levels of expression (ETP-ALL TI, n = 1; non-ETP ALL TII, n = 2; TIV, n = 1). This evidence concerns the gene NCAM1 and acute lymphoblastic leukemia.