Test Details: CD20 is a non-glycosylated surface phosphoprotein which is expressed on mature and most malignant B cells, in a subpopulation of T lymphocytes and follicular dendritic cells. It regulates transmembrane calcium conductance, cell cycle progression and B-cell proliferation. The CD20 flow cytometry assay quantitatively measures therapeutic B-cell depletion for patients on monoclonal anti-CD20 therapy such as Rituximab, and identification of B cell lymphoma, also helps to take decision on targeted therapies like anti CD20 monoclonal antibody and disease monitoring.