What is radiation therapy?

When a breast tumor is large or not easily removed by surgery, radiation therapy before surgery may help to shrink the breast tumor. After breast-sparing surgery, radiation treatments may help destroy remaining breast cancer cells.

Radiation therapies for breast cancer include:

Accelerated partial breast irradiation (APBI): This breast radiation therapy delivers focused radiation specifically to the part of the breast where the tumor was removed.

Some advantages of APBI for breast cancer may include:

• Radiation is contained to the tumor cavity as much as possible.
• Because the radiation is so targeted, it affects less of the healthy tissue and organs close to the breasts, including the lungs, heart, ribs, muscles and skin.
• It can be delivered in a more condensed schedule than some other radiation therapies for breast cancer (five days instead of six to seven weeks).

AccuBoost^®: This breast-conservation therapy delivers a targeted dose of radiation directly to the tissue surrounding the tumor bed. Potential advantages of AccuBoost for breast cancer include:

• The noninvasive procedure may be performed in an outpatient setting.
• The targeted dose is designed to help contain the radiation treatment to the lumpectomy site as much as possible.
• By delivering a measured dose that matches the size, shape and location of the target site, AccuBoost is designed to limit toxicity and overexposure to the breast.
• Providing targeted, measured, therapeutic doses is designed to produce fewer radiation-related side effects.

Calypso^® 4D Localization System™: This technology allows radiation oncologists to deliver focused doses of radiation with greater precision for breast cancer patients.

Before treatment, transponders are placed on the skin near the middle of the patient’s chest to track respiratory movement and other patient motion. Patients are then asked to take a deep breath and hold it for a few seconds. This action expands the chest and moves the heart out of the radiotherapy beam's path. The radiation oncologist uses this “map” to deliver the prescribed radiotherapy. The technology allows for continuous monitoring during treatment and will discontinue the delivery of radiation if the patient’s breathing pattern falls outside the “mapped” treatment plan.

In the recent generation of the Calypso system, the transponders are able to show the position of the patient’s treatment target area, and automatically shut the beam off in the event of a cough, sneeze or other internal change of position that moves the treatment target area out of the X-ray beam’s path. By precise targeting and tracking and by avoiding nearby healthy tissues, Calypso is designed to reduce radiation exposure to the heart, lungs and other healthy tissues.

External beam radiation therapy (EBRT): The most common type of radiation therapy for breast cancer, EBRT is usually given about a month after surgery, to give surgical wounds time to heal. It may also be used in combination with chemotherapy and may be delayed until chemotherapy is complete.

In EBRT, a beam of radiation, similar to but stronger than an X-ray, is focused on the spot where the cancer was removed. If a lumpectomy was performed, a patient may receive EBRT to the entire breast, a technique called whole-breast radiation. EBRT may also be delivered to nearby lymph nodes.

Some advantages of EBRT for breast cancer patients may include:

• It is fast, painless and performed as an outpatient procedure.
• Unlike chemotherapy, which circulates throughout the body, EBRT is targeted to the treatment area.
• There is no risk of radioactivity to you or your friends and family.

High-dose rate (HDR) brachytherapy: This type of internal radiation therapy delivers radiation from implants placed close to, or inside, the tumor(s) in the body.

Advantages of HDR brachytherapy for breast cancer may include:

• It delivers a precise, highly concentrated dose of radiation directly to the breast tumor.
• It limits radiation exposure to healthy surrounding breast tissue, reducing some of the side effects associated with standard radiation.
• After a series of treatments, the catheters are removed and there are no radioactive seeds left in the body.
• HDR brachytherapy may also be used following surgery, like a lumpectomy, to help destroy cancerous cells that remain after the procedure.

Hyperthermia: Hyperthermia (meaning elevated temperature) destroys cancer cells by raising the tumor temperature to a “high fever” range, similar to the way the body uses fever naturally when combating other conditions.

Breast cancer hyperthermia helps make breast cancer cells more vulnerable to the effects of other treatments, like breast cancer radiation therapy and certain chemotherapy drugs.

Radiation oncologists typically use hyperthermia to treat superficial breast tumors located within a few centimeters from the surface of the body.

Intensity modulated radiation therapy (IMRT): Advanced software plans a precise dose of radiation, based on tumor size, shape and location. A computer-controlled device called a linear accelerator delivers radiation in sculpted doses that match the 3-D geometrical shape of the tumor, including concave and complex shapes.

Advantages of IMRT for breast cancer may include:

• IMRT employs an advanced computer program to map your radiation dosage in three dimensions, based on the breast tumor’s size, shape and location.
• IMRT directs radiation at the breast tumor and modulates the intensity of the radiation beams, helping to spare healthy tissue surrounding the breast tumor.
• IMRT allows each dose of radiation to be custom-tailored according to the geometrical shape of the breast tumor.

IMRT breast cancer radiation therapy may be used in conjunction with other treatments. It may be an appropriate option for those who have previously had breast cancer radiation therapy and are experiencing recurrent tumors in the treated area.

Intraoperative radiation therapy (IORT): IORT delivers a concentrated dose of radiation therapy to a tumor bed during surgery. This technology may help kill microscopic disease, reduce radiation treatment times or provide an added radiation "boost."

IORT is performed immediately following the removal of a breast lump and before the lumpectomy incision is closed. A large dose of radiation is focused directly on the surgery site.

A patient must be a surgical candidate in order to be eligible for breast cancer IORT. This treatment is generally reserved for patients with early-stage disease.

MammoSite^® Radiation Therapy System (RTS): A form of brachytherapy targeted specifically for breast cancer treatment, MammoSite RTS uses a catheter to place radioactive pellets (seeds) directly in the area where a breast tumor has been surgically removed via lumpectomy.

Advantages of MammoSite RTS for breast cancer may include:

• MammoSite RTS calls for a single balloon catheter to administer radiation treatment. Standard breast brachytherapy involves surgically implanting up to 24 catheters into the breast.
• By delivering internal doses of radiation directly to breast tumors, MammoSite RTS may help avoid damage to surrounding healthy breast tissue and may reduce some of the side effects associated with external beam radiation therapy.
• With its precise, site-specific approach, this form of breast cancer radiation therapy may be completed in as few as four or five days, compared to seven weeks for traditional external beam radiation therapy.

TomoTherapy^®: This technology combines a form of intensity modulated radiation therapy (IMRT) with the accuracy of computed tomography (CT) scanning technology, in one machine.

Advantages of TomoTherapy for breast cancer may include:

• It combines state-of-the-art intensity modulated radiation therapy (IMRT) with an on-board CT scanner that allows for advanced and precise targeting of the radiation beams.
• By contouring the radiation beams to the tumor’s exact shape and position before each breast cancer treatment begins, the TomoTherapy system may reduce damage to healthy surrounding breast tissue.
• While traditional breast cancer radiation therapies project radiation onto a tumor from only a few directions, TomoTherapy delivers precise doses of radiation to breast tumors from a full 360 degrees.

If you have advanced-stage or recurrent cancer and are no longer able to receive traditional radiation, TomoTherapy may be a breast cancer treatment option. TomoTherapy may also be an option for breast cancer patients who have reached their maximum tolerated dose of traditional radiation. This therapy can re-treat previously radiated areas with high doses of radiation and with pinpoint accuracy.

Trilogy^®: This radiation therapy system provides intensity modulated radiation therapy (IMRT), image guided radiation therapy (IGRT), stereotactic radiosurgery (SRS) and fractionated stereotactic radiation therapy—all from one machine.

With Trilogy, radiation oncologists deliver sculpted radiation beams to breast tumors, while protecting the surrounding healthy breast tissue and reducing your time on the treatment table.

TrueBeam^®: This software and respiratory tracking system enables us to confirm the location of the breast tumor, track its movement and help avoid damage to healthy surrounding tissue.

A tumor in the breast can move as you breathe, making it difficult to target it accurately with standard radiation. As a result, the tumor may not receive enough radiation and healthy tissue near the tumor may be damaged.

Side effects of radiation therapy for breast cancer

Radiation therapy for breast cancer may cause short-term or long-term side effects. Short term side effects of internal or external beam radiation include:

• Redness, bruising or discoloration of the skin
• Breast pain and/or swelling
• Fatigue

Patients, especially those who had radiation therapy at a young age, are at higher risk for developing a second cancer later in life. Other long-term side effects of radiation for breast cancer include:

• Changes to the feel or size of the breast
• Difficulty breastfeeding
• Nerve damage that may lead to weakness, numbness or pain
• Damage to the lymph system resulting in lymphedema
• Bone weakness and fractures
• Damage to other organs exposed to radiation

At Cancer Treatment Centers of America^® (CTCA), our cancer experts use sophisticated tools and technology designed to limit the exposure of healthy tissue to radiation. One such tool is the Access Prone 360™ Board. This specially designed board was developed to help spare healthy tissue in vital organs from unnecessary radiation exposure. The board—a modified version of the table patients lie on while receiving radiation treatments—has an open space for the patient’s left breast. When the patient is lying face down, the breast naturally hangs through the opening and away from the body. The radiation beams then have a clear path to the breast without affecting the heart or lungs. This may also benefit early-stage breast cancer patients, by exposing only part of the breast to radiation while avoiding tissue in other areas of the breast—and the organs behind it.

Next topic: How is breast cancer treated with surgery?