What Are Rectal Spacers?

Prostate cancer is the most common type of cancer in men and the second leading cause of cancer deaths in men. In the United States, between 9 and 10 percent of men will develop prostate cancer sometime during their lives.^1,2

If you or someone you love receives a prostate cancer diagnosis, one of the most common forms of treatment is radiation. Radiation, when given in high doses, can be successful in the treatment of prostate cancer.³

The radiation targets cancer cells in the prostate and destroys them. About the size of a walnut, the prostate is located below the bladder and in front of the rectum. Because of its location, radiation can sometimes damage healthy tissue surrounding the prostate and the rectum. This can lead to diarrhea, pain, bleeding, and other conditions.³

Your doctor may want to use a rectal spacer before you begin radiation. Using this technique may prevent uncomfortable side effects and damage to the rectum. The use of rectal spacers has increased over recent years.³

What do rectal spacers do?

Rectal spacers push the rectum away from the prostate. They help doctors target the radiation exactly where it needs to go – on the prostate and away from other tissues. Spacers can help ensure treatment is delivered the same way every time.⁵

Spacers may also reduce other side effects of prostate cancer, especially urinary and sexual symptoms.⁶

Are there different types?

Currently, there are 2 different types of spacers doctors use for prostate cancer. One is a saline-filled balloon. Saline is a mixture of salt and water.⁴

The other type of spacer is made of hydrogel. Hydrogel contains polyethylene glycol. It is a substance sometimes used to repair damaged tissue in the eye, brain, or spine.⁴

How are they inserted?

Whether you receive a hydrogel spacer or a saline balloon, the procedure is quick and minimally invasive. You will not have to spend the night at the hospital and should be able to go home shortly after the procedure.

In most cases, doctors use local anesthesia (medicine is used to numb the area). Doctors sometimes use general anesthesia, which puts you to sleep. Your doctor will talk to you about which option is right for you. In both cases, you will need to arrange for someone to drive you home after the procedure.³

During the procedure, your doctor will insert an ultrasound probe into your rectum to guide the process. Your doctor will then insert a needle into the perineum (the skin between your anus and scrotum) to inject the rectal spacer. You may feel pressure or pinching during this process, but you should not have pain. Once inserted, spacers create a distance of 1.0 to 1.5 centimeters between the prostate and rectum.³

Once the spacer is in, it will stay there for the length of your treatment. Your body will absorb it, and the spacer will eventually be filtered out through your kidneys when you urinate.⁵

When doctors insert the rectal spacer, they may also place small markers called fiducial markers. About the size of a grain of rice, they help doctors further target the delivery of radiation.⁵

What happens after it's inserted?

After your procedure, you may feel fullness in your rectum for a couple of days. Your doctor most likely will prescribe an antibiotic to prevent any type of infection. Soon after you receive your spacer, your doctors will start your radiation treatment.⁵

How do rectal spacers help with prostate cancer treatment?

Spacers may help reduce the harmful effects of radiation therapy and also can improve targeting. Using spacers may allow doctors to use higher doses of radiation therapy, improving outcomes for people with prostate cancer. For example, instead of 45 treatments, you may only need 5.⁶

Where can I get more information?

Talking to your doctor is the best resource for determining if a rectal spacer is right for you. Your doctor can make recommendations about what type of spacer – hydrogel or saline balloon – you need. They can answer any questions you may have about the procedure and its benefits.

Would you like to talk to others in the prostate community about rectal spacers? Reach out in our forums.