Radiation therapy is a form of cancer treatment that uses high levels of radiation to kill cancer cells or keep them from growing and dividing -- while minimizing damage to healthy cells.

Radiation is delivered to the affected breast and, in some cases, to the lymph nodes under the arm or at the collarbone.

Radiation therapy is usually given after a lumpectomy and sometimes after a mastectomy to reduce your risk of local recurrence of cancer in that breast. The treatments generally start several weeks after the surgery so the area has some time to heal. If your doctor recommends chemotherapy along with radiation therapy, this might be given before you start radiation therapy.

Once radiation treatments start, you can expect to receive small daily doses of radiation over a period of several days to several weeks.

The radiation therapist will escort you into the treatment room. The therapist will help you onto the treatment table and help place you in the correct treatment position. Once the therapist is sure you are positioned correctly, he or she will leave the room and start the radiation treatment.

You will be under constant observation during the treatment. Cameras and an intercom are in the treatment room, so the therapist can always see and hear you. If you should have a problem, you can let the therapist know. It is very important that you remain still and relaxed during treatment.

The therapist will be in and out of the room to reposition the machine and change your position. The treatment machine will not touch you and you will feel nothing during the treatment. Once your treatment is complete, the therapist will help you get off the treatment table.

The radiation therapist will take a "port film," also known as an X-ray, on the first day of treatment and approximately every week thereafter. Port films verify that you are being accurately positioned during your treatments.

Port films do not provide diagnostic information, so radiation therapists cannot learn about your progress from these films. However, port films are important to help the therapists maintain precision in your treatment.

Small marks resembling freckles will be tattooed on your skin along the treatment area by the radiation therapist. These marks provide a permanent outline of your treatment area. Do not try to wash these marks off or retouch them if they fade. The therapist will remark the treatment area when necessary.

Yes. Good nutrition is an important part of recovering from the side effects of radiation therapy. When you are eating well, you have the energy to do the activities you want to do, and your body is able to heal and fight infection. Most importantly, good nutrition can give you a sense of well-being. Since eating when you don't feel well can be difficult, a dietitian can help you find ways to get the nutrients you need during your radiation therapy.

During your treatment, radiation must pass through your skin. You may notice some skin changes in the area exposed to radiation. Your skin may become red, swollen, warm, and sensitive -- as if you had a sunburn. It may peel or become moist and tender. Depending on the dose of radiation you receive, you may notice a loss of hair or decreased perspiration within the treated area.

These skin reactions are common and temporary -- they will subside gradually within four to six weeks of completing treatment. If skin changes appear outside the treated area, inform your doctor or primary nurse.

Long-term side effects, which can last up to a year or longer after treatment, may include a slight darkening of the skin, enlarged pores on the breast, increased or decreased sensitivity of the skin, a thickening of breast tissue or skin, and a change in the size of the breast.

• Gently cleanse the treated area using lukewarm water and a mild soap such as Ivory, Dove, Neutrogena, Basis, Castille, or Aveeno Oatmeal Soap. Do not rub your skin. Pat your skin dry with a soft towel or use a hair dryer on a cool setting.

• Do not scratch or rub the treated area.

• Do not apply any ointment, cream, lotion or powder to the treated area unless your radiation oncologist or nurse has prescribed it.

• Do not apply cosmetics, shaving lotions, perfumes, or deodorants on the treated area.

• Use only an electric razor if you need to shave within the treated area.

• Do not wear tight-fitting clothing or clothes made from harsh fabrics such as wool or corduroy -- these fabrics can irritate the skin. Instead, choose clothes made from natural fibers such as cotton.

• Do not apply medical tape or bandages to the treated area.

• Do not expose the treated area to extreme heat or cold. Avoid using an electric heating pad, hot water bottle or ice pack.

• Do not expose the treated area to direct sunlight -- sun exposure may intensify your skin reaction and lead to severe sunburn. Choose a sunblock/sunscreen of SPF 15 or higher. Protect yourself from direct sunlight even after your course of treatment has been completed.

Everyone has a different level of energy, so radiation treatment will affect each patient differently. Patients frequently experience fatigue after several weeks of treatment. For most patients, this fatigue is mild. However, a loss of energy may require other patients to change their daily routine.

If your doctor thinks it may be necessary for you to limit your activity, he or she will discuss it with you.

To minimize fatigue while you are receiving radiation treatment:

• Be sure to get enough rest.
• Eat a well-balanced, nutritious diet.
• Pace your activities and plan frequent rest periods.

Generally, a social worker will be available to help you during your course of treatment.

The social worker can discuss any emotional issues or other concerns about your treatment or your personal situation. The social worker can also discuss housing or transportation needs or appropriate resources if necessary.

People dealing with certain medical issues often find it helpful to share experiences with others in the same situation. Your physician can provide a list of support groups if you are interested. Your social worker can provide additional information about more support groups that may be of value to you.

After your radiation therapy sessions are complete, you will visit your doctor for periodic follow-up exams and diagnostic X-rays. Your doctor will tell you how often to schedule your follow-up appointments.

Reviewed by the doctors at The Cleveland Clinic Taussig Cancer Center.

Edited by Charlotte E. Grayson, MD, WebMD, February 2004.

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