Waldenström Macroglobulinemia (WM) is a lymphoplasmacytic lymphoma (LPL) with bone marrow (BM) involvement by small lymphocytes admixed with variable numbers of plasmacytoid lymphocytes and plasma cells accompanied by IgM monoclonal gammopathy of any concentration [1,2,3]. The gene discussed is CD40LG; the disease is Waldenstrom macroglobulinemia.