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Failed Barrigel injection and insertion of only 3 of 4 carbon markers
I had a procedure earlier this week in preparation for upcoming 20 sessions of photon beam therapy to (i) insert Barrigel between my prostate and rectal wall; and (ii) insert 4 carbon fiducial markers into the prostate.
I was informed later that day that the surgeon was unable to inject the Barrigel because I had no perirectal fat (one of the cons of a low-fat diet? lol). I obviously want as much protection to my rectum as possible and do not like the probability of having the photon beam treatments with my prostate basically touching my rectal wall. Is there anything that can be done about this?
On the following day after my MRI I read that:
“Three fiducial markers are in place, two on the right and one on the left. The 4th fiducial marker that was placed at the left base is not well delineated.”
It seems that there is a reason that they want 4 markers and not 3 or 5. I am assuming that the most accurate delivery of the radiation occurs when all 4 carbon markers are accurately observed. Is there anything that can be done about this? Can the surgeon insert at 5th marker to take the place of the 4th?
Thanks.
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Only had 3 markers placed (gold). No issues with targeting. Did not have any rectal spacer nor was it offered. Full bladder, empty bowel routine is critical! This worked for me...
https://www.nutrition.va.gov/docs/Oncology/RadiationTherapyforProstateCancerNutritionMar2025.pdf
That was Oct 2025. So far, so good. Good luck!
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Hug
2 ReactionsNot all rectal spacers require existing, natural fat to work, but most commonly used hydrogel spacers (like SpaceOAR) are injected into the perirectal fat layer to create space. The spacer acts as a temporary, synthetic barrier that separates the rectum from the prostate to reduce radiation exposure.
There are three spacers, One of the other two may work
SpaceOAR, or BioProtect
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2 Reactions@mjp0512
Thanks. I believe that you posted this link in another thread as I remember reading it.
@jeffmarc
Well, according to my RO and my "AI" (lol), SpaceOAR, Barrigel, and BioProtect all need to be injected into the perirectal fat (which, for some inexplicable reason I am missing). This is depressing news.
Also, if they can perform accurate photon therapy with 3 carbon markers, why do theyt inject 4? My RO at Mayo says it doesn't matter?
Have some further conversation with your oncologist. I had SpaceOar successfully placed as well as the desired markers, but with 44 IMRT treatments over a year ago am still dealing with radiation proctitis. Make sure that risks and likely outcomes are discussed well.
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1 Reaction@jime51 Good post! I don’t think the radiation proctitis risk can be overstated. I had no issues with the marker placement or the Spacer gel placement. 5 months post sbrt and never a bowel issue. When you do the math, each sbrt treatment is placing 8 times the radiation that your 44 treatments placed. Even with a 20 session regimen it is important for the radiation planning and delivery to be as accurate as possible
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1 ReactionI concluded that having a rectal spacer put in prior to radiation therapy was a good thing so I agreed to it and the procedure was done. I haven't had the radiation yet. If they had told me they couldn't do it, I would have been disappointed, but what do I know? I just liked the sound of getting the rectum further away from getting fried by the external beam.
It isn't a 100% beneficial, nothing can go wrong type of thing. There are pros and cons.
John Sylvester gave a lecture entitled "Risks and Complications of Rectal Spacers" at an Oct 2025 Symposium on PCa. He is generally in favor of them, but.... "Dr. Sylvester highlights that while rectal spacers reliably reduce rectal dose and low-grade toxicity, they introduce procedural risk, do not reduce severe toxicity, [ i.e. the rare Grade 3] and may negatively impact quality of life." https://grandroundsinurology.com/risks-and-complications-of-rectal-spacers/
The symposium also featured a lecture by Brian Davis: "Advantages of Prostate Cancer Rectal Spacers" "Using case examples, Dr. Davis discusses the benefits of hydrodissection for safety, symmetry, and anatomical confirmation during spacer placement. He reasserts that data illustrating the advantages of rectal spacing supports its use across multiple prostate radiation modalities."
https://grandroundsinurology.com/advantages-of-prostate-cancer-rectal-spacers/
If SpaceOAR, Barrigel, and BioProtect aren’t viable options, perhaps you could try the old endo-rectal balloons.
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Hug
1 ReactionIt looks like the endo-rectal balloons (other than BioProtect) are inflated inside the rectum rather than between the prostate and rectum?
I can't imagine 3 markers not being completely sufficient. Mine only called for two, though it was the longer & thinner wire style so the irregular shape probably helps see the orientation better.
Your stress about no spacer is understandable. As Brian mentioned maybe old style balloon inserted into the rectum would be an option. Plus I keep reading comments lately that some facilities have stopped suggesting spacers since the imaging and targeting have improved so much in recent years. If you don't already know the specifics, you might discuss with your doctor to make sure you're getting the most advanced imaging and guidance available to you, like the MRI guided systems.