What Is Stereotactic Body Radiotherapy (SBRT)?

Medically Reviewed by Poonam Sachdev on April 28, 2022
4 min read

If you have certain kinds of cancer, such as lung cancer or pancreatic cancer, your doctor may suggest you get a type of radiation therapy called stereotactic body radiotherapy (SBRT). It's a very precise method that lets your doctor accurately target your tumors.

When you have SBRT, your doctor will use a computer to direct many radiation beams to your tumor from different angles. Because it's so accurate in hitting the right spot, you can get a higher dose of radiation than you could with standard radiation therapy. There's less concern of damaging nearby, healthy tissue.

Your doctor may recommend SBRT if you have cancer of the:

  • Lung
  • Liver
  • Prostate
  • Pancreas

You may also get SBRT if your cancer has returned or you have a tumor that can't be treated with other types of radiation

Another reason for SBRT is that your cancer has spread to the adrenal glands (one adrenal gland sits on top of each kidney), liver, lungs, or spine.

If you're getting radiation to treat cancer, an important person on your medical team will be a radiation oncologist. They are a doctor with special training in how to use radiation therapy.

Your radiation oncologist will work with other specialists to plan the best way to target the radiation beam at your tumor. This team may include a:

  • Radiation oncology nurse, who can answer questions and help manage side effects
  • Medical radiation physicist, who helps plan your radiation treatment
  • Dosimetrist, who helps figure out the right dose of radiation
  • Radiation therapist or technologist, who operates the radiation machine
  • Social worker
  • Nutritionist or dietitian
  • Physical therapist
  • Dentist, if you are getting radiation near your mouth


Radiation damages the DNA of your cancer cells so they can no longer grow and divide. Eventually, the cancer cells die and your tumor gets smaller.

SBRT is an "external radiation therapy," which means a doctor directs the radiation at the tumor from outside your body.

Your doctor will look at your medical records and scans to decide if SBRT is a good choice for you and how many treatments you'll need. Some people have only one treatment. Others may get up to five.

You'll have an appointment with your radiation oncology team a week before you start SBRT. At this visit, your doctors will run through how the treatment will go. This is called your simulation appointment.

Your doctors will use imaging scans, such as CT scans, MRIs, and X-rays, to see exactly where your tumor is. This will help them figure out the best way to use the beams to target your cancer and keep the radiation away from nearby tissue and organs.

Your doctor may put a small mark on your skin. This will help the team target the beam when you come back for treatment.

Your doctor may also put special markers, called fiducial markers, inside your body. They are usually made from gold and are about the size of a grain of rice. They are put on or near the tumor to help your doctors direct the radiation beams. You might get these markers if your cancer is in your:

  • Belly
  • Chest
  • Head and Neck
  • Pelvis (the lower part of your belly, below your navel and between your hips)

You may be fitted for a special bed that will keep you from moving while you are getting SBRT. Depending on where your cancer is, your doctors may use:

  • Tape
  • Sponges
  • A headrest
  • Special molds
  • Plaster casts

You may also need to be fitted for a special mask if you will be getting radiation to your head or neck.

Before the procedure starts, your doctor will give you medication to help you feel less anxious, if you need it.

When you get your SBRT, you'll be in the same position that you were in during the simulation. If your medical team made a special bed for you, you'll lie on it. You'll also use a special mask on your face if it was made for you.

A radiologist will use the CT scanner that's part of the radiation machine to see your tumor. The team will then use the machine to deliver the radiation beams, which will take just a few minutes. You won't feel any pain.

The most common side effects of SBRT are:

  • Feeling tired
  • Redness, like sunburn, at the place on your body where you got the radiation
  • Itchiness in the area of the radiation
  • Swelling in the spot you had the radiation
  • Nausea or vomiting if the tumor is near your bowel or liver

Depending on where your cancer is, you may have other side effects. Talk to your doctor about:

  • Organs near your tumor that might be affected
  • Side effects you may have if these organs get damaged
  • How to manage side effects
  • Who to call if you have any problems after your treatment

To help your treatment go easier, try these tips:

  • Get as much rest as possible.
  • Eat a healthy diet.
  • Talk to others who have had SBRT.
  • Ask your team about skin lotions that can help with pain or itchiness from radiation.
  • Stay out of the sun as much as possible.