Carcinoma of the breast - partial radiation therapy; Partial external beam radiation - breast; Intensity-modulated radiation therapy - breast cancer; IMRT - breast cancer WBRT; Adjuvant partial breast - IMRT; APBI - IMRT; Accelerated partial breast irradiation - IMRT; Conformal external beam radiation - breast
Partial breast radiation therapy uses high-powered x-rays to kill breast cancer cells. It is also called accelerated partial breast radiation (APBI). A standard course of external beam breast treatment takes 3 to 6 weeks. APBI can be accomplished in as little as 1 to 2 weeks. APBI targets a high dose of radiation on the area where the breast tumor was removed. It avoids exposing the surrounding tissue to radiation. There are three common approaches for APBI:
- External beam, the topic of this article
- Brachytherapy (inserting radioactive sources into the breast)
- Intraoperative radiation (delivering radiation at the time of surgery in the operating room)
Radiation therapy is usually delivered on an outpatient basis, except for intraoperative radiation therapy.
Two common techniques are used for partial breast external beam radiation treatment:
- Conformal external beam radiation
- Intensity-modulated radiation therapy (IMRT)
Before you have any radiation treatment, you will meet with the radiation oncologist. This person is a doctor who specializes in radiation therapy.
- The doctor will put small marks put on your skin. These marks ensure that you are correctly positioned during your treatments.
- These marks will either be ink marks or a permanent tattoo. Do not wash ink marks off until your treatment is finished. They will fade over time.
The treatment is usually given 5 days a week for anywhere from 2 to 6 weeks. It may sometimes be given twice a day (usually with 4 to 6 hours between sessions).
- During each treatment session you will lie on a special table, either on your back or your stomach.
- The technicians will position you so the radiation targets the treatment area.
- You may be asked to hold your breath while the radiation is being delivered. This helps limit how much radiation your heart receives.
- Most often, you will receive radiation treatment for between 1 and 5 minutes. You will be in and out of the cancer center within 15 to 20 minutes on average.
Rest assured, you are not radioactive after these radiation treatments. It is safe to be around others, including babies and children.
Why the Procedure Is Performed
APBI is used to prevent breast cancer from coming back. When radiation therapy is given after breast-conserving surgery, it is called adjuvant (additional) radiation therapy.
APBI may be given after lumpectomy or partial mastectomy (called breast-conserving surgery) for:
- Ductal carcinoma (DCIS)
- Stage I or II breast cancer
Before the Procedure
Tell your health care provider what medicines you are taking.
Wear loose fitting clothes to the treatments.
After the Procedure
Radiation therapy can also damage or kill healthy cells. The death of healthy cells can lead to side effects. These side effects depend on the dose of radiation and how often you have the therapy. Radiation can have short-term (acute) or long-term (later) side effects.
Short-term side effects can begin within days or weeks after treatment begins. Most side effects of this type go away within 4 to 6 weeks after treatment ends. Most common short-term effects include:
- Breast redness, tenderness, sensitivity
- Breast swelling or edema
- Breast infection (rare)
Long-term side effects may begin months or years after treatment and may include:
- Decreased breast size
- Increased firmness of breast
- Skin redness and discoloration
- In rare cases, rib fractures, heart problems (more likely for left breast radiation), or lung inflammation (called pneumonitis) or the development of second cancer years later
- Arm swelling (edema) -- more common if lymph nodes were surgically removed and if the armpit area was treated with radiation
Your providers will explain care at home during and after radiation treatment.
Partial breast radiation following breast conservation therapy reduces the risk of cancer coming back, and possibly even death from breast cancer.
National Cancer Institute website. Breast cancer treatment (adult) (PDQ) - health professional version. www.cancer.gov/types/breast/hp/adult/breast-treatment-pdq. Updated October 11, 2019. Accessed October 15, 2019.
National Cancer Institute website. Radiation therapy and you: support for people who have cancer. www.cancer.gov/publications/patient-education/radiationttherapy.pdf. Updated October 2016. Accessed August 2, 2018.
Shah C, Harris EE, Holmes D, Vicini FA. Partial breast irradiation: accelerated and intraoperative. In: Bland KI, Copeland EM, Klimberg S, eds. The Breast: Comprehensive Management of Benign and Malignant Diseases. 5th ed. Philadelphia, PA: Elsevier; 2018:chap 51.