Radiation therapy (or radiotherapy) uses high-energy rays to stop cancer cells from growing and dividing. Radiation therapy is often used to destroy any remaining breast cancer cells in the breast, chest wall, or axilla (underarm) area after surgery. Occasionally, radiation therapy is used before surgery to shrink the size of a tumor. A common treatment for earlystage breast cancer is breast-conserving therapy. Breast-conserving therapy (BCT) is the surgical removal of a breast lump (lumpectomy) and a surrounding margin of normal breast tissue. BCT is typically followed by at least six to seven weeks of radiation therapy. Treatment with radiation usually begins one month after surgery, allowing the breast tissue adequate time to heal. Radiation therapy may occasionally be recommended for women to destroy remaining cancer cells after mastectomy (surgical removal of the affected breast) or to shrink tumors in patients with advanced breast cancer.
The most common type of radiation therapy used on women with breast cancer is called external beam radiation. External beam radiation is delivered from a source outside the body on the specific area of the body that has been affected by the cancer. Experts compare the experience of external beam radiation to having a diagnostic x-ray, except that radiation is usually administered for a longer period of time and at a higher dose.
Before radiation therapy begins, the physician will measure the correct angles for aiming the radiation beam at the specific area of the body and make ink marks on the patient’s skin. As part of treatment after breast surgery, patients are typically treated with radiation five times per week for at least six weeks in an outpatient clinical setting. Each treatment generally lasts a few minutes; the entire radiation session after machine set-up typically lasts 15 to 30 minutes. The procedure itself is pain-free. While the radiation is being administered, the technologist will leave the room and monitor the patient on a closed-circuit television. However, patients should be able to communicate with the technologist at any time over an intercom system. Learn more about what to expect during a radiation session.
Side effects of external beam therapy vary among patients. The most common side effect is fatigue. Fatigue (extreme tiredness) can be especially bothersome in the later weeks of treatment. Patients who experience fatigue after radiation sessions should get plenty of rest and try to maintain an active lifestyle. While many patients can still work and participate in normal activities during radiation therapy, some patients find it necessary to limit their work or activities until treatment has been completed.
Other common side effects of radiation therapy are neutropenia (sharp decrease in white blood cell count) swelling of the breast, a feeling of heaviness in the breast, a sunburn-type appearance of the breast skin, and loss of appetite. These side effects usually disappear after six to 12 months. Near the end of treatment with radiation, the breast skin may become moist. Patients should try to wearing loose fitting clothing and expose the skin to air as much as possible to help the skin heal quickly.
Temporary Side Effects of Radiation Therapy
- Fatigue
- Neutropenia (reduction in white blood cells)
- Breast swelling or tenderness
- Feeling of heaviness in the breast
- Sunburn-like appearance of the breast skin
- Loss of appetite
In most cases, the breast will look and feel the same after radiation therapy is completed, though it may be more firm. In rare cases, radiation therapy may cause changes in the breast size. Breasts may become larger due to fluid build-up (seroma) or smaller due to tissue changes. Some women may find that the breast skin is more sensitive after radiation, while others may find that it is less sensitive. Radiation therapy of the axillary (underarm) lymph nodes may cause lymphedema (chronic swelling of the arm) in some women. Women who have radiation to the lymph nodes will usually be instructed on arm exercises and other activities to help prevent lymphedema. Pregnant women are usually advised not to undergo radiation therapy because of possible harm to the fetus. More information on breast cancer and pregnancy.
The following recommendations may help reduce pain from skin reactions to radiation therapy:
- Avoid any additional sun exposure to the area
- Wear loose-fitting clothing, preferably cotton or other material that "breathes"
- Use warm or tepid water when bathing, rather than hot water
- Avoid constricting bras (if a bra must be worn at all)
- Use cool compresses (not cold or ice packs, as that may cause additional skin damage)
- Lotions or powders on the treated area are generally not recommended
- Specific creams should be approved by the radiation oncologist or his/her nurse. Often, there should not be any substance on the skin that could affect the radiation treatment or lead to a more serious burn injury (such as oil).
Patients should talk to their physicians about soothing oils or creams that may be allowed between (not during) treatment sessions.