A diagnosis of CLL requires the presence of ≥5000 clonal B-lymphocytes/μL in the PB, together with CD5, CD19, and CD23 antigen expression and light-chain surface immunoglobulin (SIg) restriction, confirmed by flow cytometry, for a duration of at least three months [1,2]. Here, CD19 is linked to B-cell chronic lymphocytic leukemia.