Multiple myeloma: a review

Multiple myeloma is an incurable malignant tumour of plasma cells of the bone marrow and is the most common primary neoplasm arising in bone. Most patients have disseminated disease and a poor prognosis. Orthopaedic and spinal surgeons are likely to be exposed to such patients, as myeloma forms a common differential amongst osteolytic lesions after the 5th decade. Myeloma leads to variable renal impairment, anaemia, hypercalcaemia, infection and pathological fractures. Osteolytic lesions, generalised bone loss and elevated bone turnover precipitate pathologic fractures due to complex interactions between bone marrow stromal cells, osteoblasts, osteoclasts and myeloma cells within the bone marrow microenvironment. Survival rates vary greatly; mean five and 10-year survival rates are estimated to be 68% and 55% respectively. The International Staging System for multiple myeloma defines three risk categories, as determined by the serum concentration of β2-microglobulin and albumin. Cytogenetic testing for specific mutations can identify patients at particularly high risk of morbidity and mortality. Management includes the use of chemotherapy, radiotherapy, haemopoietic stem cell transplant and bisphosphonates. Surgical intervention is indicated for (impending) pathological fractures and to decompress and stabilise spinal cord compression. Orthopaedic surgeons must be aware of the pathoaetiology and disease-related complications in multiple myeloma patients who may require urgent surgical intervention.