Fig. 1.
The results of a diagnostic work-up of a 21-year-old patient with CRLF2-rearranged BCR/ABL1-like ALL. a Peripheral blood smear. Blasts (pointed with arrows) with scant cytoplasm, dispersed nuclear chromatin, and prominent nucleoli. Wright’s stain (×100 magnification). b Bone marrow aspirate smear. Blasts are pointed with arrows. Wright’s stain (×20 magnification). c Multicolor FC analysis. Side scatter versus CD45. Violet, blasts. Red, and other cells. d Multicolor FC analysis of CRLF2 expression on leukemic blasts. Violet, CRLF2-positive blasts; green, other cells. In the presented case, the 10-color FC (BD FacsCanto II IlyricTM) analysis revealed: CD13 0.0%, CD33 80%, CD34 94%, CD117 0.0%, HLA DR 99%, CD38 92%, CD31 100%, CD36 0.0%, CD14 0.0%, CD11b 0.0%, CD11c 0.0%, CD64 0.0%, CD163 0.0%, CD18 0.0%, CD56 0.0%, CD16 0.0%, CD19 99%, CD10 97%, CD20 90%, CD22 96%, CD3 0.0%, CD5 0.0%, CD4 0.0%, CD8 0.0%, CD7 0.0%, CD2 0.0%, CD1a 0.0%, CD66b 0.0%, CD66c 0.0%, CD65 0.0%, CD15 77%, CD123 0.0%, CRLF2 79%, cytCD68 0.0%, MPO 0.0%, TdT 99%, cytCD3 0.0%, cytCD79a 91%, cytIgM 0.0%, kappa 0.0%, lambda 0.0%, CD45 dim. FSC low, SSC low/mid (personal data). CRLF2, cytokine receptor-like factor 2; FC, flow cytometry.