What to Know About Radiation Therapy for Breast Cancer

According to the National Cancer Institute, radiation therapy uses high energy rays or particles to kill cancer cells.

Radiation kills or slows the growth of cancer cells. It also affects nearby healthy cells, but the healthy cells typically recover after the course of radiation treatment has ended. Doctors try to protect healthy cells by:

• using as low a dose of radiation as possible
• spreading out treatment over time
• aiming the radiation at a very specific part of your body

Radiation therapy can be used in a variety of instances for breast cancer treatment. It can be used:

• after breast-conserving surgery, to reduce the risk of recurrence in your breast
• after a mastectomy, particularly if:
  • the tumor was larger than 5 centimeters
  • there was cancer in your lymph nodes
  • the margins were positive
• to help ease side effects if the cancer spreads to other areas of your body, such as your bones or brain

Depending on the type of breast cancer and the cancer stage, radiation may be used in combination with other cancer treatments, such as surgery and chemotherapy.

There are two main types of radiation therapy: external beam radiation and internal radiation. Some people receive both types of treatment.

External beam radiation

External beam radiation is the most common type of radiation therapy for breast cancer.

During this treatment, a large machine sends beams of radiation to the area of your breast that is affected by cancer.

The beams are aimed directly at the site of your tumor. While the machine moves around you, it can send radiation to your tumor from different directions.

Internal radiation

Internal radiation involves putting a source of radiation into your body. This type of radiation treatment is also known as brachytherapy.

For this treatment, healthcare professionals will temporarily place a device with radioactive seeds or pellets into your breast tissue in the area where the tumor was located. To treat breast cancer, internal radiation is often given through one or more catheters (small tubes).

Some factors, such as the size and location of the tumor, can limit who can receive this type of radiation therapy.

Internal radiation typically works well when:

• breast cancer is in an early stage
• cancer is present in just one spot in your breast
• you’ve had breast-conserving surgery

Knowing what to expect before radiation therapy can help you better prepare for the treatment and address any concerns you might have ahead of time.

What to expect with external beam radiation

If you receive external beam radiation, you’ll meet with your radiation oncologist and a nurse before starting treatment. They will walk you through what to expect during external beam radiation, as well as the risks and benefits of this treatment.

At that time, you’ll likely have a physical exam and go over your medical history.

Additionally, the radiation oncologist and a radiation therapist will take scans of your treatment area. This will help them define the boundaries of the affected area so they know where to aim the radiation beams.

They will put marks (tattoos or ink) on your skin to identify the area. You’ll need the marks throughout the course of your treatment. Healthcare professionals will use the marks to line up your body so that the radiation beams target the exact area that needs to be treated.

In some cases, healthcare professionals may make a body mold to help keep you still during the treatment.

Each treatment will last only a few minutes. In fact, the session setup will take longer than the actual treatment. You won’t feel anything when the machine is turned on for the treatment. It is a painless procedure.

What to expect with internal radiation

Before you get any internal radiation, you’ll meet with your radiation oncologist. They will:

• perform a physical exam
• ask about your medical history
• go over what your internal radiation treatment will involve

Most internal radiation is given through a catheter. This is a small, flexible tube that’s surgically placed into the space that’s left after breast-conserving surgery.

At the end of the catheter is a device that can be inflated inside your breast so that it stays in place for the duration of the treatment.

During your treatment, a healthcare professional will insert radiation pellets or seeds through the catheter and into the inflatable device. The pellets will usually stay there for 10 to 20 minutes or longer, and then the healthcare professional will remove them. How long the radiation pellets stay in place depends on:

• your type of cancer
• your overall health
• other cancer treatments you’ve had

Once the course of treatment is over, healthcare professionals will remove the catheter and the inflatable device.

Radiation therapy usually begins 3 to 4 weeks after a breast-conserving surgery or a mastectomy.

External beam radiation is typically given once per day, 5 days per week, for 2 to 10 weeks on an outpatient basis. This means you can go home after the treatment.

The schedule for external radiation may differ from the standard schedule in cases such as the following:

• Accelerated fractionation: Treatment is given in larger daily or weekly doses, reducing the duration of the treatment.
• Hyperfractionation: Smaller doses of radiation are given more than once per day.
• Hypofractionation: Larger doses of radiation are given once daily (or less often) to reduce the number of treatments.

For internal radiation, treatments are usually given twice per day for 5 days in a row as outpatient procedures. Your specific treatment schedule will depend on what your oncologist has ordered.

A less common treatment option is to leave the radiation in your body for hours or days. During this type of treatment, you’ll stay in the hospital to protect others from the radiation.

Common side effects of external beam radiation therapy for breast cancer include:

• sunburn-like skin irritation in the treatment area
• dry, itchy, tender skin
• fatigue
• swelling or heaviness in your breast

Skin changes and changes to your breast tissue usually go away within a few months to a year.

Hair loss from radiation typically occurs only in areas that are radiated. If you receive external beam radiation to your breast, you typically won’t lose your hair on your head. You may lose hair in your armpits, depending on the area being radiated.

External beam radiation can also have long-term effects, which may:

• cause your breast to become smaller and harder
• make breastfeeding more difficult
• affect your reconstruction options
• affect nerves in your arm

Internal radiation typically has fewer side effects than external beam radiation. The most common side effects are:

• redness or other skin color changes and bruising
• breast pain
• infection
• fatty tissue damage
• fluid buildup in your breast
• weakness in and fractures of your ribs (in rare cases)

Many side effects of radiation go away within a few months of the end of your treatment. There are steps you can take to help minimize some of the side effects.

If you have persistent side effects, talk with your doctor.

Radiation therapy for breast cancer is a common treatment that kills or slows the growth of cancer cells. While it also affects nearby healthy cells, these cells usually recover after the treatment ends.

Radiation therapy can be used alone or with other treatments, such as surgery and chemotherapy.

Two common types of radiation treatment for breast cancer are external beam radiation and internal radiation, which is also known as brachytherapy. Internal radiation typically has fewer side effects.

The type of radiation that’s best suited for you depends on:

• the type and stage of your breast cancer
• your overall health
• other cancer treatments you’ve had

Talk with your doctor about your treatment options. Together, you can make the treatment decisions that are right for you.