Characterized by circulating monoclonal immunoglobulins due to a clonal proliferation of immunoglobulin producing B lymphocytes or plasma cells.
Clonal proliferation of B lymphocytes seen in B cell type llymphomas, B cell type leukemias, and clonal plasma cell proliferation seen in multiple myeloma and monoclonal gammopathy of undetermined significance.
Proliferating monoclonal cells secrete immunoglobulin which can be detected in the blood or urine as a monoclonal immunoglobulin, M protein.
Frequently associated with secretion of light chain component of the immunoglobulin molecule kappa or lambda light chains, in addition to intact immunoglobulin, suggesting dysregulation of the normal antibody synthetic pathway.
Neoplastic cells may lose the ability to synthesize normal heavy chain component of the immunoglobulin molecule and secrete only Kappa or lambda light chains.
Clinical spectrum of monoclonal gammopathy includes malignant processes such as multiple myeloma, Waldenström’s macroglobulinemia, non-malignant paraprotein related disorders, including light chain amyloidosis, and premalignant plasma cell dyscrasias monoclonal gammopathy of undetermined significance.