Radiation Therapy for Breast Cancer

This treatment uses high levels of radiation to kill cancer cells or keep them from growing and dividing. Because it targets the disease, it minimizes damage to healthy cells.

Will I Need Radiation?

Your doctor may recommend it after a lumpectomy (a breast-preserving surgery to remove a tumor) or after a mastectomy to lower the odds of the cancer returning in that breast.

You may also have radiation to treat some symptoms of advanced cancer.

Treatments generally start several weeks after surgery, so your body has some time to heal. If your doctor recommends chemotherapy too, you might start chemo first.

What Types of the Therapy Might My Doctor Recommend?

External beam radiation is most commonly used to treat breast cancer. A machine outside your body aims a beam of radiation on the area affected by the disease.

Brachytherapy delivers radiation to the cancer through something implanted in your body.

What to Expect With External Beam Radiation

Your therapist will escort you into the treatment room and help you get in the right position. Then she'll leave the room and start the treatment.

It's important to hold still and stay relaxed. Cameras and an intercom allow the therapist to see and hear you. Tell her right away if you're concerned about something.

The therapist will be in and out of the room to reposition the machine and your body. The machine won’t touch you, and you won’t have any pain during the treatment.

Your therapist verifies you're in the right position by taking an X-ray called a "port film" on your first day of treatment and every week thereafter. These films don't show how your cancer is responding.

Why Are There Marks on My Skin?

Small marks that look like freckles are tattooed on your skin along the treatment area when you have external beam radiation. They give your medical team an outline of that area. 

Don’t try to wash these marks off or retouch them if they fade. The therapist will re-mark the treatment area when needed.


What Are the Side Effects of External Beam Radiation?

Radiation passes through your skin, which can become red, swollen, warm, and sensitive -- as if you had a sunburn. It may peel or become moist and tender. Depending on the dose, you may lose hair or sweat less where you've been treated.

These skin reactions are common and short-term. They usually go away gradually within 4 to 6 weeks after your last treatment. Tell your doctor or nurse if you see skin changes outside the treated area.

Long-term side effects can last beyond a year after treatment. They may include a slight darkening of your skin, enlarged pores on your breast, more or less sensitive skin, thickening of breast tissue or skin, and a change in the size of the breast.

A rare complication of radiation is getting a new cancer or tumor where the radiation is given. Talk to your doctor about this risk.

How Can I Lessen Skin Reactions?

  • Gently cleanse the treated area using lukewarm water and a mild soap. Don’t rub your skin. Pat it dry with a soft towel, or use a hair dryer on a cool setting.
  • Don’t scratch or rub the treated area.
  • Don’t apply any ointment, cream, lotion, or powder to the treated area unless your doctor or nurse has prescribed it.
  • Don’t apply cosmetics, shaving lotions, perfumes, or deodorants on the treated area.
  • Use only an electric razor if you need to shave within the area.
  • Don’t wear tight-fitting clothing or harsh fabrics like wool or corduroy. Instead, choose clothes made from natural fibers like cotton.
  • Don’t put medical tape or bandages on the treated area.
  • Avoid extreme heat or cold where you've had radiation. Don't use an electric heating pad, hot water bottle, or ice pack.
  • Avoid direct sunlight, especially between the hours of 10 a.m. and 2 p.m., even after your course of treatment has been completed. It can intensify skin reactions and lead to severe sunburn. Choose a sunscreen of SPF 30 or higher. Wear protective clothing, such as a long-sleeved shirt, pants, and a wide-brimmed hat, too.


What to Expect With Brachytherapy

Radioactive seeds or pellets as small as grains of rice are placed inside the breast, near the cancer. Whether this treatment might be right for you will depend on your tumor’s size, location, and other things. 

The side effects include redness, bruising, breast pain, infection, weakness, and an increased risk of fractured ribs. 

Brachytherapy can be used alone or with external beam radiation.

How Should I Eat During a Course of Radiation?

Good nutrition is important to help you recover from side effects. Eating well gives you energy and helps your body heal and fight off infection. It can also give you a sense of well-being.

Since eating when you don't feel good can be hard, a dietitian can help you find ways to get the nutrients you need during treatment.

Will Radiation Make Me Tired?

Everyone has a different level of energy, so radiation affects each person differently. Many people feel fatigued after several weeks of treatment. Most often, this is mild. But some people feel more tired and may need to change their daily routines.

Your doctor will let you know if she thinks you should limit your activities.

To keep your energy during radiation treatments:

  • Get enough rest.
  • Eat a well-balanced, nutritious diet.
  • Pace your activities, and plan frequent rest periods.

Who Can I Talk to About My Treatments?

Your doctor can answer questions about side effects, the goals of your treatment, and how the cancer is responding to radiation.

You can talk to a hospital social worker about your feelings, family concerns, financial issues, and other aspects of your personal situation. If you don’t live close to where you’re being treated, you may be able to get help with housing or transportation.

Great support and practical tips can come from talking with other people with cancer. Ask your doctor or social worker how to find good support groups near you or online.

What Happens After Radiation Therapy?

You'll see your doctor for follow-up exams and X-rays. She’ll tell you how often to come in.

WebMD Medical Reference Reviewed by Jennifer Robinson, MD on May 07, 2015



American Cancer Society.

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