Myeloma

Abstract

Multiple myeloma (MM) is a clonal malignant disorder of mature B-lymphocytes characterized by extensive proliferation and accumulation of aberrant plasma cells in the bone marrow. Extramedullary disease, containing clusters of malignant plasma cells, occurs in some patients and is referred to as plasmacytoma. MM is preceded by an asymptomatic premalignant disorder, monoclonal gammopathy of undetermined significance (MGUS), in almost all patients. Clinical manifestations due to disruption of normal hematopoiesis and immune dysfunction include fatigue, anemia and infections. Osteolytic bone disease is a major cause of morbidity in MM and is associated with hypercalcemia, osteopenia, and pathologic fractures. Monoclonal immunoglobulin or M-protein secreted by the clonal plasma cells may lead to renal insufficiency, and peripheral neuropathy. Despite a significant in improvement of survival over the past decade with the advent of novel biologic therapeutic agents, MM is considered an incurable disease. Risk adapted therapy with incorporation of novel agents is recommended for the initial treatment of MM with consideration for autologous hematopoietic stem cell transplantation in eligible patients. In this chapter, the epidemiology, pathogenesis of bone disease in MM, diagnosis, and treatment principles of MM are discussed.