The Role of CD20 in the Diagnosis, Classification, and Management of Lymphomas: A Narrative Review
Abstract: CD20 is a non-glycosylated transmembrane phosphoprotein encoded by the MS4A1 gene and expressed on the surface of B lymphocytes from the late pro-B-cell stage through the memory B-cell stage, but not on early progenitors or terminally differentiated plasma cells. Because of this restricted and stable expression pattern, CD20 has become the single most widely used immunohistochemical marker for confirming B-cell lineage in the diagnostic work-up of lymphoid neoplasms, and it forms the basis of the classic CD3/CD20/CD45 triage panel used to separate T-cell, B-cell, and non-lymphoid processes. This narrative review summarizes current evidence on the biology of CD20, its diagnostic role across B-cell non-Hodgkin lymphoma subtypes and classic versus nodular lymphocyte-predominant Hodgkin lymphoma, the diagnostic pitfalls posed by CD20-negative and CD20-aberrant lymphomas, the prognostic implications of reduced or lost CD20 expression, and the marker's central role as the target of rituximab and other anti-CD20 monoclonal antibodies. Across the reviewed literature, CD20 consistently emerges as the most reliable single marker for B-lineage assignment, while also functioning as a direct link between diagnosis and immunotherapy, underscoring the value of accurate, standardized CD20 assessment in routine pathology practice.
Keywords: CD20, lymphoma, immunohistochemistry, B-cell markers, non-Hodgkin lymphoma, rituximab
How to Cite?: Leen Naif Almohammadi, "The Role of CD20 in the Diagnosis, Classification, and Management of Lymphomas: A Narrative Review", Volume 15 Issue 10, October 2026, International Journal of Science and Research (IJSR), Pages: 441-445, https://www.ijsr.net/getabstract.php?paperid=SR26807155312, DOI: https://dx.doi.org/10.21275/SR26807155312