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Radiation Therapy FAQ

What is radiation therapy?

Radiation therapy, also called radiotherapy, uses various forms of radiation to treat tumors and other medical conditions. Unlike radiology, a medical specialty that uses low-energy X-rays to take images of patients, radiation therapy uses high-energy radiation to treat conditions.

More than half of all people diagnosed with cancer are treated with radiotherapy. 

How does it work?

The goal of radiation therapy is to damage the genes that allow tumor cells, which grow faster than normal cells, to divide and spread. Your radiation oncologist works closely with your physicians to individually tailor the intensity of the radiation to the precise area to be treated. Our treatments are designed to limit the radiation exposure to surrounding healthy tissue and reduce side effects.

For many patients, radiation is the only treatment needed. In other cases, it's provided first to shrink a tumor before surgery or afterward to destroy any remaining cancer cells. Radiotherapy is also used to provide relief from painful and difficult symptoms caused by a tumor.

How is radiation therapy given?

Radiotherapy can be delivered to the outside of the body or internally. Most patients receive external beam radiotherapy from a machine known as a linear accelerator. This technology directs high-energy X-rays or electrons at tumors.

Treatment is typically given daily on an outpatient basis for several weeks, although a doctor may sometimes order several treatments per day. Internal radiation therapy, also called brachytherapy, involves implanting a radioactive source next to or inside the tumor, usually with a small plastic or metal tube temporarily inserted in the body to hold the material in place.

Depending on the dosage, this form of radiotherapy can be delivered on an outpatient basis or require hospital admission. Some patients may require both external and internal forms of radiotherapy.

What can I expect before and during treatment?

You’ll be directed to a patient changing area where you’ll have access to a locker to secure your clothing and belongings. Wear comfortable clothing that is easy to remove. In the treatment room, a radiation therapist will assist you throughout the procedure. The therapist will help you with proper placement on the treatment table.

The equipment makes a high-pitched noise when activated, so patients are encouraged to bring music to play on a stereo system in the treatment area. Patients are in constant contact with the radiation therapists. During the delivery of brief bursts of radiation, the therapist stays in contact through a video camera and audio system. Treatments can be halted immediately in an emergency.

How do my doctors know exactly where to direct the radiation?

Our radiation specialists use computed tomography (CT) scans, magnetic resonance imaging (MRI) scans and positron emission tomography (PET) scans. These generate a sophisticated computer treatment simulation, giving a three-dimensional view of the tumor inside the body as well as calculating the amount of radiation it should receive.

Once a patient is on the treatment table, X-ray images are taken to help correlate the body’s position with that of the tumor. This data is used to ensure exact delivery of the radiation beams with a precision of less than a millimeter variance for each subsequent treatment.

What side effects can I expect?

Your physician will discuss possible side effects that you may experience from the radiation treatments. Please inform our radiation therapy team about any symptoms you may be experiencing as well as any changes in your medications.

In general, a patient’s skin is very sensitive during radiation treatment. We recommend wearing loose-fitting clothing during your course of treatment to avoid friction with your skin. Avoid direct sunlight on the area treated. Your doctor can recommend lotions to sooth your skin, which should be applied after daily treatments.

Other recommendations include:

  • Do not use deodorant, lotion, perfume or cologne on the skin being treated with radiation.
  • Avoid applying lotions to your skin prior to a treatment.
  • Do not shave the hair in the area under treatment.
  • Do not use ice or hot packs on the skin area under treatment.
  • Note that commercial deodorants contain metals that react with the skin. Many lotions also contain alcohol that can irritate your skin.

Please consult your nurses or the therapists for any questions regarding skin care.

For more information or to arrange a consultation, please call 714-456-5651.

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