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Radiation Therapy for Multiple Myeloma

Radiation therapy uses high-energy rays or particles to kill cancer cells. 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 vertebral (back) bones, these bones can collapse and put pressure on the spinal cord and spinal nerves. Symptoms 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; patients with these symptoms should call their doctor right away. Prompt treatment with radiation therapy and/or surgery is often needed to prevent paralysis.

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. Having radiation therapy is much like having a diagnostic x-ray except that each treatment lasts longer, and the course of treatment can continue for several weeks.

Side effects of radiation can include:

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

These symptoms improve once treatment is over.

More information about radiation therapy

To learn more about how radiation is used to treat cancer, see Radiation Therapy.

To learn about some of the side effects listed here and how to manage them, see Managing Cancer-related Side Effects.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.

Munshi NC, Anderson KC. Ch. 112 Plasma cell neoplasms. In: DeVita VT, Hellman S, Rosenberg SA, eds. Cancer: Principles and Practice of Oncology. 10th edition. Philadelphia, PA: Lippincott Williams & Wilkins; 2015.

Rajkumar SV, Dispenzieri A. Multiple myeloma and related disorders. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE. Abeloff’s Clinical Oncology. 5th edition. Philadelphia, PA. Elsevier: 2014:1991-2017.

Last Revised: February 28, 2018

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