Quantitative flow cytometry based on PE-conjugated mAb 2A2 and QuantiBRITE PE beads as standard, estimated the number of ROR1 molecules on the cell surface of primary ALL blasts from three patients with MFI scores of “+”, “++”, and “+++” at 2,494, 3,715, and 4,591, respectively (Table 1). The gene discussed is ROR1; the disease is acute lymphoblastic leukemia.