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Radiation therapy for breast cancer

Radiation therapy for breast cancer uses high-energy X-rays, protons or other particles to kill cancer cells. Rapidly growing cells, such as cancer cells, are more susceptible to the effects of radiation therapy than are normal cells.

The X-rays or particles are painless and invisible. You are not radioactive after treatment, so it is safe to be around other people, including children.

Radiation therapy for breast cancer may be delivered through:

Radiation therapy may be used to treat breast cancer at almost every stage. Radiation therapy is an effective way to reduce your risk of breast cancer recurring after surgery. 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).

Radiation therapy kills cancer cells. It’s often used after surgery to reduce the risk that the cancer will come back. It can also be used to provide relief from pain and other symptoms of advanced breast cancer.

Radiation after lumpectomy

If you’re having an operation to remove the breast cancer and leave the remaining breast tissue intact (lumpectomy or breast-conserving surgery), your doctor may recommend radiation after your procedure to kill any cancer cells that might remain. Adding radiation after a lumpectomy reduces the risk that cancer will return in the affected breast.

Lumpectomy combined with radiation therapy is often referred to as breast conservation therapy. This type of treatment is as effective as having all the breast tissue removed (mastectomy). In special situations where the risk of recurrence is very low, your doctor may also discuss the option of avoiding radiation after a lumpectomy.

After lumpectomy, radiation treatment options might include:

Radiation after mastectomy

Radiation can also be used after mastectomy. In this situation, the radiation can kill any cancer cells that might remain and reduce the risk that the cancer may recur in the remaining tissues of the chest wall or lymph nodes.

When determining whether you should undergo radiation after mastectomy, your doctor considers whether you have:

Radiation for locally advanced breast cancer

Radiation therapy can also be used to treat:

Radiation for managing metastatic breast cancer

If your breast cancer has spread (metastasized) to other parts of your body, radiation therapy may be recommended to shrink the cancer and help control symptoms such as pain.

Side effects from radiation therapy differ significantly depending on the type of treatment and which tissues are treated. Side effects tend to be most significant toward the end of your radiation treatment. After your sessions are complete, it may be several days or weeks before side effects clear up.

Common side effects during treatment may include:

Depending on which tissues are exposed, radiation therapy may cause or increase the risk of:

Rarely, radiation therapy may cause or increase the risk of:

Before your radiation treatments, you’ll meet with your radiation therapy team, which may include:

Before you begin treatment, your radiation oncologist will review your medical history with you and give you a physical exam to determine whether you would benefit from radiation therapy. Your doctor will also discuss the potential benefits and side effects of your radiation therapy.

Before external radiation therapy

Before your first treatment session, you’ll go through a radiation therapy planning session (simulation), in which a radiation oncologist carefully maps your breast area to target the precise location of your treatment. During the simulation:

Before internal radiation therapy

Before internal radiation therapy (brachytherapy) is started, a special device for placement of the radioactive material is placed in the area where the cancer was removed. This may be done during your cancer surgery or as a separate procedure several days later.

Radiation therapy usually begins three to eight weeks after surgery unless chemotherapy is planned. When chemotherapy is planned, radiation usually starts three to four weeks after chemotherapy is finished. You will likely have radiation therapy as an outpatient at a hospital or other treatment facility.

A common treatment schedule (course) historically has included one radiation treatment a day, five days a week (usually Monday through Friday), for five or six weeks. This course is still commonly used in people who require radiation to the lymph nodes.

Increasingly, doctors are recommending shorter treatment schedules (hypofractionated treatment). Whole-breast irradiation can frequently be shortened to one to four weeks. Partial-breast irradiation may be completed in five days or less. These hypofractionated treatment schedules work as well as the longer one and may reduce the risk of some side effects. Your radiation oncologist can help decide the course that is right for you.

During external radiation

A typical external radiation therapy session generally follows this process:

Delivery of the radiation may last only a few minutes, but expect to spend 15 to 45 minutes for each session, as it can take several minutes to set you up in the exact same position each day. This step ensures precise radiation therapy delivery.

Radiation therapy is painless. You may feel some discomfort from lying in the required position, but this is generally short-lived.

After the session, you’re free to go about your regular activities. Take any self-care steps at home that your doctor or nurse recommends, such as taking care of your skin.

In some situations, once the main radiation therapy sessions have been completed, your doctor may recommend a radiation boost. This commonly means additional fractions of radiation directed at the place of highest concern or four to five additional days of treatment. For example, after whole-breast irradiation is complete, a boost of radiation is commonly given to the area where the cancer was removed.

During internal radiation

For internal radiation, the radioactive source is inserted once or twice a day for a few minutes in the implanted radiation delivery device. This is usually done on an outpatient basis and you can leave between sessions.

After the course of treatment, the radiation delivery device is removed. You may be given pain medication before this happens. The area may be sore or tender for several days or weeks as the tissue recovers from the surgery and radiation.

After you complete radiation therapy, your radiation oncologist or other medical professionals will schedule follow-up visits to monitor your progress, look for late side effects and check for signs of cancer recurrence. Make a list of questions you want to ask members of your care team.

After your radiation therapy is completed, tell your medical professional if you experience:

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