SpaceOAR® Hydrogel

Missouri Cancer Associates and Urology Associates of Central Missouri are working together to provide comprehensive, compassionate cancer care, offering state-of-the-art treatment for prostate cancer. Patients who require radiation treatment for prostate cancer can now receive the SpaceOar® (OAR stands for “organ at risk”) System. The SpaceOar® System is a temporary injectable gel that protects the rectum in men undergoing prostate cancer radiation treatment either with external radiation (IMRT) or even with internal treatment aka Seeds. SpaceOar® Hydrogel is made of polyethylene glycol (PEG). PEG is widely used in cosmetics and drugs because it is non-toxic and well tolerated by the body. SpaceOar® Hydrogel is injected as a liquid that, within seconds, solidifies into a soft, gel-like synthetic material that expands and creates space between the prostate and rectum. Because it contains mostly water, it is called a “hydrogel.”

FDA approval occurred after the results of a phase III trial that demonstrated a significant reduction in the radiation dose to the rectum which translated into a significant decrease in side effects. The reduction in radiation dose to the rectum was approximately 75% with zero patients having grade 2 or greater rectal toxicity 3 years after treatment.  

SpaceOAR® Hydrogel

The SpaceOar® System is placed in a patient by a Urologist in an outpatient setting prior to external radiation treatment through a minimally invasive, outpatient procedure. The SpaceOar® Hydrogel is injected through a small needle into the space between the prostate and rectum while the patient is under local or general anesthesia. It is inserted during the same procedure where small gold markers (called fiducials) are placed in the prostate to localize it prior to each radiation treatment or immediately following placement of the radioactive seeds used in brachytherapy for prostate cancer.

Ultrasound imaging allows the urologist to see and place the hydrogel in the proper location. On average, SpaceOar® Hydrogel creates about 0.5 inch (or 1.3 cm) of space between the prostate and rectum, permitting radiation treatment to the prostate with much less rectum radiation injury and fewer complications. The gel remains in place for about three months during radiation treatment, and then liquefies and is absorbed and cleared from the body in the patient’s urine.

Missouri Cancer Associates is proud to hold the Radiation Oncology Practice Accreditation (ROPA) from the American College of Radiology (ACR) for Radiation Oncology Services. To learn more about radiation treatments available, click here.

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Frequently Asked Questions (FAQs)
SpaceOAR® hydrogel (OAR stands for “organ at risk” which in this case is the rectum), helps protect your rectum during radiation treatments to the prostate. Naturally, you may have questions about how and why the procedure is done, and what to expect. This section will help to answer many of the questions you may have about the procedure. It is not intended to be a substitute for a thorough discussion with your physician. If you don’t see the answer you’re looking for, please feel free to contact us at (WHO TO CALL?)

Is it safe?
SpaceOAR® hydrogel is mostly made of water, is biocompatible and is safely used in the body. Similar hydrogels are used as surgical sealants on the brain, spine, and eyes. SpaceOAR® hydrogel is cleared for use in the United States and approved in countries outside the United States.

Will I feel any pain during or after the procedure?
Your doctor will use an anesthetic to reduce or eliminate any discomfort with the procedure. Patients that have SpaceOAR® hydrogel implanted typically report no prolonged discomfort after the procedure.

Will this procedure interfere with my normal activities?
You should be able to immediately resume your normal activities. Always be sure to check with your doctor for any restrictions related to the procedure and your radiation treatment.

Why should I have SpaceOAR® hydrogel?
The goal of radiation therapy is to maximize radiation to the prostate and to avoid radiating surrounding normal tissue. The prostate and rectum are very close and are only naturally separated by a small space. Due to this closeness, prostate radiation therapy can accidentally cause damage to the rectum.

What is SpaceOAR® hydrogel and how will it benefit me?
SpaceOAR® hydrogel is a gel-like material that temporarily moves the rectal wall away from the prostate during radiotherapy. By separating the prostate from the rectum, SpaceOAR® hydrogel reduces radiation dose delivered to the rectum and may eliminate or reduce damage to the rectum. It may also allow your doctor to enhance radiation treatment to your prostate to better target the cancer or to reduce the total number of treatment sessions.

What is it made of and is it safe?
SpaceOAR® hydrogel is made of two liquids that when combined form a soft gel-like synthetic material that is mostly made of water. Because of its water content it is called a hydrogel. The material that the SpaceOAR® hydrogel is made from has been used in other implants such as surgical sealants used in the eye, brain and spine. Studies have shown that the material is biocompatible and can be used safely in the body.

Where is the procedure done?
The procedure is commonly done in a hospital, surgery center, outpatient clinic or doctor’s office.

How is it implanted?
SpaceOAR® hydrogel is injected between the rectum and the prostate in a minimally invasive procedure.

Will I be awake or asleep during the procedure?
The procedure can be performed under general, regional or local anesthesia. You should discuss with your doctor which type of anesthesia is best for you.

Do I have to do any special preparation prior to the procedure?
While there is no required special preparation for the SpaceOAR® hydrogel procedure, your doctor may give you individual instructions on how to prepare for the procedure and for any anesthesia you will receive. Always ask your doctor what you should do in advance of the procedure.

Will I feel any discomfort or pain during or after the procedure?
Your doctor will either use an anesthetic that will put you to sleep during the procedure or a local anesthetic that will numb the injection area. You may feel a pinprick or pressure but should not feel any major discomfort. After the procedure you may experience some temporary discomfort at the injection site. SpaceOAR® hydrogel patients typically report no prolonged discomfort from the implanted hydrogel.

How soon can I go back to my normal activities?
You should be able to immediately resume your normal activities. Always be sure to check with your doctor for any restrictions associated with the procedure and your radiation treatment.

How long does it stay in my body?
SpaceOAR® hydrogel separates your prostate and rectum for about 3 months providing protection during radiation treatment and is naturally absorbed in about six months – well after your last treatment.