A Rare Presentation of Biclonal Gammopathy in Multiple Myeloma with Simultaneous Extramedullary Involvement: A Case Report

Multiple myeloma is characterized by an abnormal clone of plasma cell infiltration in the bone marrow and presence of a high level monoclonal immunoglobulin (M-protein) in the serum or urine in most cases. The monoclonal protein is usually detected as a discrete band in the gamma globulin region by serum protein electrophoresis. Rarely, it may show a simultaneous presence of two distinct bands, which could be either from a single clone, or two separate clones. We report a very unusual presentation of biclonality with lambda restricted IgG predominant cells from cervical lymph node and kappa restricted IgA cells from the bone marrow simultaneously.