Multiple myeloma is a relatively common malignancy of the hematologic system (10-15% of hematologic malignancies) that affects predominantly the elderly, the average age of the involved patients usually falling within 60 to 70 years. It is slightly more male-predominant, and it is particularly more common in African-American population. It is a part of a spectrum of disease known as plasma cell dyscrasias, where there is an uncontrolled proliferation of plasma cells in the absence of identifiable antigenic stimulus.1

The classical clinical presentation of a patient with multiple myeloma is usually related to bone pain, as proliferation of abnormal plasma cells create a mechanical burden on the skeleton by displacing and eroding bony trabeculae. These days, about two-thirds of patients with multiple myeloma present with bone pain. The rest are discovered incidentally during a work-up of something entirely unrelated.2 A patient can also present with constitutional symptoms such as fever along with the bone pain. A patient can also have renal and cardiac failure due to amyloidosis caused by the excessive proteins produced by the plasma cells.1

Predominant pattern of radiologic features of multiple myeloma is osteolysis. Axial skeleton is the predominant site of involvement. The classical multiple myeloma lesions are osteolytic lesions with discrete margins. In long bones, the subcortical circular or elliptical lytic lesions can cuase erosion of the inner margins of the cortex, giving the endosteal bone a scalloped and/or wavy contour. Diffuse skeletal osteopenia can be observed in multiple myeloma, stimulating the appearance of osteoporosis.

Treatment of multiple myeloma usually involves the use of systemic chemotherapy. The induction agents are usually prednisone and some sort of alkylating agent, usually melphalan. Local radiotherapy or decompressive surgery is used for bony lesions, particularly in the axial skeleton causing neurologic symptoms by compression of the cord. Finally, allogeneic stem-cell marrow transplantation is currently being offered to selected patients.2