Radiation Therapy for Breast Cancer

Radiation therapy uses ionizing radiation, such as high-energy X-rays or particles, to treat cancer. It damages cancer cells’ DNA, keeps them from growing and dividing, and minimizes damage to healthy cells.

For most people, radiation begins three to four weeks after surgery to destroy undetectable cancer cells and reduce the risk of relapse (cancer recurring in the affected breast).

Radiation therapy is a painless procedure and an effective way to reduce the risk of breast cancer recurring after surgery by approximately 50 percent.

In addition, it is commonly used to ease the symptoms caused by cancer that has spread to other parts of the body (metastatic breast cancer) or improve the quality of life.

The two predominant types of radiation therapy used to treat breast cancer are:

1. External beam breast cancer radiation
   • The most used for any type of breast cancer.
   • A large machine (linear accelerator) uses highly focused external beam radiation, such as X-rays, to target the cancerous area for two to three minutes five days a week for up to five or six weeks.
   • Can be used simultaneously with some treatments after surgery, such as hormone therapy or HER2-targeted therapy.
   • Further divided into subtypes:
     • Whole breast radiation: Entire breast receives high-powered X-rays to kill breast cancer cells.
     • Accelerated partial breast irradiation:
       • Intraoperative radiation therapy: The entire course of radiation is delivered at one time during breast cancer surgery.
       • 3D-conformal radiotherapy: Helps direct radiation beams to conform the tumor shape. It spares normal breast tissues in the surroundings.
       • Intensity-modulated radiotherapy: An advanced type of radiation that delivers precise radiation to a tumor while minimizing the dose to surrounding normal tissue.
   • Lymph node radiation (chest wall radiation): Targets the lymph nodes in the breast and chest wall to kill any cancer cells that might present in the nearby lymph nodes.
2. Brachytherapy or internal breast cancer radiation
   • Uses devices containing radioactive seeds or pellets, which are placed into the affected breast tissue for a short time.
   • Further divided into:
     • Intracavitary brachytherapy: An applicator with a radioactive substance is placed at or near the site of tumor removal (body cavity).
     • Interstitial brachytherapy: Devices containing radioactive material are placed within the breast tissue to destroy cancer cells.

Radiation therapy can be a part of the treatment regimen for people with:

• Stage 0 cancer
• Stage I invasive cancer or higher
• A history of lumpectomy

Radiation therapy is used in situations, such as:

• After breast-conserving surgery
• Before surgery
• When surgery is not an option
• After a mastectomy
• If cancer has spread to other parts of the body (bones, spinal cord, or brain)

Radiation therapy is not a safe option for pregnant individuals.

The intensity and frequency of side effects of radiation therapy may vary among people. They often include:

• Skin reactions, such as:
  • Red, dry, tender, or itchy skin
  • Peeling or flaking
  • Discoloration, redness, or a bruised appearance
  • Moist or weepy skin
  • Sunburn-type skin irritation and darkening of the targeted area
• Breast swelling heaviness
• Changes in the shape, size, and color of the breast
• Painful breast
• Rib tenderness
• Fatigue (extreme tiredness)
• Hair loss in the armpit
• Sore throat
• Lymphedema

In some rare cases, radiation therapy can increase the risk of:

• Rib fracture
• Chest wall tenderness
• Inflamed lung tissue (radiation pneumonitis or pulmonary fibrosis)
• Heart damage (cardiotoxicity, atherosclerosis arrhythmias, and heart valve disease)
• Nerve damage to the arms and shoulders (brachial plexopathy)
• Secondary cancer (bone, muscle, or lung cancer)

Though the issues caused by radiation therapy usually go away soon, a lasting change in the color of the skin could persist longer.

Here are a few tips to deal with the most common side effects of radiation:

• Wear loose-fitting cotton clothes while in radiation therapy
• Avoid using any deodorants, lotions, or creams on the treated area
• Avoid scratching or rubbing the area
• Use only an electric razor to shave the treated area
• Avoid exposure of the treated area to extreme heat or cold
• Avoid exposure to direct sunlight
• Avoid consuming vitamin supplements, such as vitamins C, A, D, and E
• Take good care of yourself by getting plenty of rest and eating a good nutritional diet
• Routine exercise can reduce the degree of fatigue caused by radiation therapy

The other methods used for breast cancer treatment include:

• Chemotherapy
• Hormonal therapy
• Targeted therapy
• Immunotherapy
• Surgery