Heterogeneity of neoplastic cells in B-cell chronic lymphoproliferative disorders: biclonality versus intraclonal evolution of a single tumor cell clone.

Background And Objectives: B-cell chronic lymphoproliferative disorders (B-CLPD) are usually monoclonal expansions of a single B-cell clone. However in some cases, two unrelated B-cell clones co-exist. Additionally, cases with two B-cell subpopulations displaying a similar phenotype but distinct DNA contents exist, the exact nature of these cases remaining unknown.