CD5 and B-cell chronic lymphocytic leukemia: The diagnosis of CLL was confirmed for each patient by flow cytometry (EPICS XL Beckman Coulter Flow Cytometer, Miami, FL, USA), standard protocol of Beckman Coulter [19] was used in fluorescent dye labeled monoclonal antibody for CD45, CD5, CD3, CD19, CD20, CD22, CD23, FMC7, CD79b, kappa, and lambda light chain.