Multiple myeloma is cancer of the plasma cells in bone marrow.

Causes

Plasma cells help the body's immune system fight disease by producing proteins called antibodies. In multiple myeloma, plasma cells grow out of control in the bone marrow and form tumors in the areas of solid bone.

The growth of these bone tumors makes it harder for the bone marrow to make red blood cells, white blood cells, and platelets. This causes anemia, which makes a person more likely to get infections and have abnormal bleeding.

As the cancer cells grow in the bone marrow, they can cause pain and destruction of the bones. If the bones in the spine are affected, it can put pressure on the nerves, resulting in numbness or paralysis.

Multiple myeloma mainly affects older adults. A history of radiation therapy raises your risk for this type of cancer.

Symptoms

• Bleeding problems
• Bone or back pain, most often in the ribs or back
• Fevers without any other cause
• Increased susceptibility to infection
• Symptoms of anemia (such as tiredness, shortness of breath, and fatigue)
• Unexplained fractures
• Weakness of the arms or legs

Exams and Tests

Blood tests can help diagnose this disease. They may include:

• Blood chemistry may show increased levels of calcium, total protein, and abnormal kidney function
• Complete blood count (CBC) reveals low numbers of red and white blood cells and platelets
• Serum beta 2 microglobulin level
• Serum immunofixation electrophoresis
• Urine immunofixation electrophoresis
• Serum protein electrophoresis (SPEP)
• Urine protein electrophoresis (UPEP) or Bence-Jones protein analysis
• Quantitative immunoglobulins (nephelometry)
• Serum free light chain measurements

Bone x-rays may show fractures or hollowed out areas of bone. If your doctor suspects this type of cancer, a bone marrow biopsy will be performed.

Bone density testing may show bone loss.

Treatment

The goal of treatment is to relieve symptoms, avoid complications, and prolong life.

People who have mild disease or where the diagnosis is not certain are usually carefully watched without treatment. Some people have a slow-developing form of multiple myeloma that takes years to cause symptoms.

Medications for the treatment of multiple myeloma include:

• Dexamethasone, melphalan, thalidomide, lenalidomide (Revlimid), and bortezomib (Velcade) can be used alone or together.
• Drugs called bisphosphonates (pamidronate) are used to reduce bone pain and prevent fractures.

Radiation therapy may be performed to relieve bone pain or treat a bone tumor.

Two types of bone marrow transplantation may be tried:

• Autologous bone marrow or stem cell transplantation makes use of one’s own stem cells. In younger patients, it has been shown to increase survival.
• Allogeneic transplant makes use of someone else’s stem cells. This treatment carries serious risks.

People with multiple myeloma should drink plenty of fluids to prevent dehydration and help maintain proper kidney function. They should also be cautious when having x-ray tests that use contrast dye.

Support Groups

The stress of illness may be eased by joining a support group whose members share common experiences and problems. See: Cancer - support group

Outlook (Prognosis)

Survival of people with multiple myeloma depends on the patient's age and the stage of disease. Some cases are very aggressive, while others take years to get worse.

Chemotherapy and transplants rarely lead to a permanent cure.

Possible Complications

Kidney failure is a frequent complication. Other complications may include:

• Bone fractures
• High levels of calcium in the blood, which can be very dangerous
• Increased chances for infection (especially pneumonia)
• Paralysis from tumor or spinal cord compression

When to Contact a Medical Professional

Call your doctor if you have multiple myeloma and infection develops, or numbness, loss of movement, or loss of sensation develops.

Alternative Names

Plasma cell dyscrasia; Plasma cell myeloma; Malignant plasmacytoma; Plasmacytoma of bone; Myeloma - multiple