Spacer technology - separating prostate from rectal wall for radiotherapy?

Is anyone aware of treatment centers using this technology yet? I checked with Vanderbilt, and of course they don't use it yet because it hasn't been substantiated as effective through large randomized clinical trials, and so on. I'm going to have radiation therapy, and this seems like it would be very desirable to prevent injury to the rectum wall. Even using the super-duper Varian Trilogy 23X IGRT machine, the rectal wall is still right up against the prostate and so is subject to quite a bit of radiation.

The basic physics of it seem very sound. How can it not be helpful to create this separation?

Is this being used anywhere yet? There's a wiki entry about it, and apparently a commercial supplier of a "hydrogel" material. There are studies using other materials, like hyaluronic acid which is also used for sort of temporary padding in knees pending replacement surgery.

Well that's interesting. The clinical trial excludes my situation (T3a, Gleason 9). They require T1 or T2, and 7 or less Gleason. Even though they're not recruiting for the trial, it's sure curious.

I wonder why that would be? Mine is too advanced for the spacer to help? Hmmm....

It's possible with my indicated ECE in that area, could there be some attachment between the prostate and the rectal wall tissue? This was suggested as a risk for surgery. Squirting some separating stuff in that space could create a problem I suppose, if it ended up splitting something that's stuck together.

Post Edited (Redwing57) : 5/10/2013 7:04:46 PM (GMT-6)

Red wing,
We both think along the same lines although I didn't think of it until my sister mentioned that her husband has "botox" injections to relieve bladder (?) Pain.
Huum! Anyway, DRINK plenty of fluids prior to each treatment!! I must not have drank enough since I wound up with "freezer burn"..All the best to you..
Bill

I just wore my street clothes on the table, removing my belt and stuff in my pockets. They had me unbutton my jeans just enough to reveal the tattoos. In my case, the "tattoos" were little plastic dots that had to be removed after my last treatment with alcohol and didn't come off in the shower (but I only had 5 treatments). I lay on the body mold they made for me, and 5 minutes later, it was over and I left (My machine was Novalis Tx with RapidArc, which is rapid indeed.)

I've heard from some guys that they were instructed to do a fleet enema before each session, but I wasn't. I also had no special dietary instructions, but I know some guys are told to eat a low gas/low fiber diet. I only had to drink a pint of water just before each treatment to weight down my bladder and prevent movement. The fiducials were tracked during treatment with stereo X-rays, and the bench readjusted automatically as necessary.

After my fiducials were placed, they took both an MRI and a CT and fused the images. That was used to develop a treatment plan that conformed precisely to the 3D shape of my prostate. In my low risk case, the margin was zero on the rectal side and 1 mm elsewhere. They use a computer to create an optimal plan for each person's anatomy and risk level. The plan will include the dose delivered to each part of the prostate (showing isodose curves), and also the dose delivered to organs at risk (e.g., bladder and rectum) by % of the organ volume (It's called a "dose/volume histogram"). My dose dropped off very quickly outside the prostate. You can ask to have a copy of the treatment plan. It is then programmed into the computer that runs the linac machine, where there are control mechanisms to make sure the X-rays are delivered according to plan.