Radiation Therapy for Multiple Myeloma

When might radiation therapy be used?

Radiation may be used to treat areas of bone damaged by myeloma that have not responded to chemotherapy and/or other drugs and are causing pain or may be near breaking. It’s also the most common treatment for solitary plasmacytomas.

If myeloma severely weakens the bones in the spine, these bones might collapse and put pressure on the spinal cord and spinal nerves. (This is known as spinal cord compression.) Symptoms might include a sudden change in sensation (such as numbness or tingling), sudden weakness of leg muscles, or sudden problems with urination or moving the bowels. This is a medical emergency, and prompt treatment with radiation therapy and/or surgery is often needed to prevent long-term paralysis.

How is radiation therapy given?

The type of radiation therapy most often used to treat multiple myeloma or solitary plasmacytoma is called external beam radiation therapy. The radiation is aimed at the cancer from a machine outside the body.

Before your treatment starts, your radiation team will take careful measurements to find the correct angles for aiming the radiation beams and the proper dose of radiation. This planning session, called simulation, usually includes getting imaging tests such as CT or MRI scans.

The number of radiation treatments you have will depend on the reason it's being given. The treatment is much like getting an x-ray, but the radiation is stronger. The procedure itself is painless. Each treatment lasts only a few minutes, although the setup time – getting you into place for treatment – usually takes longer.

What are the side effects of radiation therapy?

Side effects of radiation depend on where the radiation is aimed. They can include:

• Skin changes in the area being treated, which can range from redness to blistering and peeling
• Fatigue (feeling very tired)
• Nausea
• Diarrhea (if the belly or pelvis is being treated)
• Low blood counts

These symptoms tend to improve shortly after treatment is over.