Any reports on using the SpaceOar

Hello

I'm starting SBRT at MSK in a few weeks and they want me to have the newer block inserted to protect the area around the prostate.

I have read varying reviews...including this study that shows its not that effective
/prostatecancerinfolink.net/2017/01/10/spaceoar-hydrogel-is-the-difference-worthwhile/

Has anyone used this? What is your opinion on the benefits vs risk and added procedure?

Thanks

I think there is a small benefit in a very few patients. It's basically a very expensive preventative for a problem (late term GI toxicity) that doesn't arise very much with modern RT techniques. I think it may be valuable in some select patients, perhaps those with IBD or with anatomical peculiarities or with tumors adjacent to the rectal wall.

I doubt it. There was really no improvement in acute rectal symptoms, and the inflammation and bleeding of pre-existing hemorrhoids is usually an acute symptom. Maybe see a proctologist now to get rid of any pre-existing hemorrhoids.

I should add that the risk of the the gel implant is pretty low. If it didn't cost $4000 or so, I wouldn't have an issue with it. With medical costs in the US skyrocketing, it's hard to justify an unnecessary expense like that. I'd bet that Zelefsky's margin at the rectum is close to 0 mm for SBRT, and I'm sure he uses very tight dose/volume constraints.

The RO who we spoke to said he felt it was a bit of marketing tool without much guaranteed benefit. When one is a patient you are pretty desperate to minimize SE's at all costs to a certain degree. I have heard of chronic bleeding bowels from someone but they may not have had treatment at a top notch facility and it was a few years ago. Bowel issues sound pretty horrific.

Notam,

Everytime insurance agrees to cover an unnecessary procedure, those who make money on it include the facility that offers it, the doctors and staff who can bill for it, and , most of all, the manufacturer. But who actually pays for it? The answer is - we all do. The insurance company just passes the costs along in increased premiums for you and all the rest of us. It also means that that insurance company may try to hold back on covering other more expensive procedures that we and our doctors believe are necessary. This isn't a no-brainer. This is why per capita health care costs in the US are twice as high as any other country and are increasing all the time. Since I can barely afford my premiums now, even with gov't subsidy, this is of great interest to me.

Notam - I had IBS for many years prior to my SBRT treatment last November. Yes, I did have some mild radiation proctitis, but it only lasted a few weeks, and in no way did it interfere with my normal life activities - including working 10 hour days and going to the gym 5 days a week. I did not have SpaceOar.

The worst side effect I've had so far is the enteritis. This is where the radiation may have exacerbated my IBS, causing abdominal/intestinal cramping and pains that seemed to move about at random. This lasted several months, but thankfully has fully resolved now.

My only lasting annoyance of treatment is what it did to my hemorrhoids. . .

For whatever it's worth, months ago my RO said he would consider using Space OAR, but that it was new and had it's own learning curve.

I've had both LUTS and ulcerative colitis for many years and the probability of radiation inflaming these conditions lead me to RALP. At least a dozen top RO's around the country all recommended surgery. Urosurgeons should only be as fotthcoming.

YMMV

fuzzboxman - I really had no reason to have anything done with my hemorrhoids prior to treatment, as they were dormant for long periods of time and caused little to no discomfort. Now, after treatment, I've had some recurrence, but over-the-counter topicals seem to work for me. Not a big deal, not cramping my lifestyle, so I just deal with it.

fuzzboxman-

Not necessarily. I certainly didn't use any enemas. Every RO has his own protocol about that - follow what he wants. Like you, I was treated on a very fast VMAT linac (treatment time was about 5 minutes), so bowel prep wasn't necessary. Those treated with CyberKnife may be on the couch for up to an hour, so a clear bowel is more important. They also may also have dietary restrictions (low residue/low gas diet) that may not apply to you. Just follow your RO's directions.

Back to Space OAR, and spacers in general, I just found this article in my files:

According to the International Foundation for Functional Gastrointestinal Disorders (IFFGD), despite the best efforts of doctors to avoid harm to the rectum and colon, “significant rectal injury remains a far too common side-effect.” This includes diarrhea, urgency, bowel incontinence, and rectal bleeding. When such problems occur during or very soon after a course of radiation, they are called acute adverse events. What most patients don’t realize is that such side effects may not show up for months or even as late as 2 years after treatment. These are called late-onset adverse effects. Another word for adverse effects is toxicities.
Gastrointestinal adverse events are ranked according to a 4-point grading scale:

Grade 1 – Mild and self-limiting. Includes bleeding, mucous discharge, mild rectal discomfort, loose stools not requiring medication.
Grade 2 – Can be managed conservatively, does not affect lifestyle. Includes intermittent rectal bleeding that does not require pad use, diarrhea requiring medications.
Grade 3 – Severe side effects that alter lifestyle. Includes rectal bleeding that requires pad use and minor surgical intervention, rectal pain requiring narcotics, and ulcerations of the rectum.
Grade 4 – Life threatening and disabling. Includes blockage of the bowel, a hole in the rectal wall (fistula), bleeding requiring hospitalization, and necessary surgical intervention
Now there is a new approach to protecting the rectum: a hydrogel that is injected into the thin layer of tissue (fascia) between the prostate and rectum to act as a “spacer.” The hydrogel is composed of two liquids (the majority of it is water) that form a biocompatible get-like substance. Injecting the hydrogel is done under general or local anesthesia, and most patients tolerate the procedure well, though as many as 10% have reported rectal pain or discomfort. As the body gradually absorbs the hydrogel (up to 12 months) the space slowly returns to normal. There are few published studies that compare spacer vs. non-spacer (control) results. The results point to similar rates of acute (short-term) adverse rectal events, but those patients who had the hydrogel had fewer late-onset toxicities than the control patients, and the toxicities were less severe.

The latest study, presented at the September 2016 annual meeting of the American Society for Radiation Oncology (ASTRO), tracked 222 patients for a median of 37 months after radiation treatment using IMRT. about 2/3 of the patients received the spacer, while 1/3 acted as a control group (no spacer). As reported by Medscape, “With regard to rectal toxicity, the control group, when compared with the hydrogel group, had a higher incidence of both grade 1+ and grade 2+ events.”[In other words, a smaller percentage of spacer patients had problems. According to a 2016 study of 30 patients, acute Grade 1 gastrointestinal toxicity rates were 43% for the spacer group vs. 50% for the control group; acute Grade 2 rates were 0% for the spacer group vs. 4.5% for the control group. Late-onset Grade 1 rates were 16.6% for the spacer group vs. 41.8% for the control group.

Meanwhile, given the risk of bowel or colon problems following prostate cancer radiation, the hydrogel spacer seems like a constructive step toward reducing bowel side effects.

Notam....I agree totally!

TA- I had read your piece when searching for info on SpaceOAR. I found it well written and very informative, as I do most all of your blog pieces (I've read the entire archive and printed several for reference). You are to be commended for your PCa advocacy, your efforts are laudable and making a positive impact.

But I'm not here for that discussion. Right now I simply want to learn about and possibly utilize any available treatment that decreases short or long term toxicity with no medical side effects. So feel free to skewer me for my selfishness (actually, please don't take THAT literally!) if I decide every fraction of every extra percentage point available today may be worth pursuing for my DW or myself.

Now in the meantime however, it appears to me that there were -zero- increases in rectal, urinary toxicities or device failures to date and the trend for all measures continued to improve. Indeed some measures failed to meet a 5% minimally important difference (MID), while others did. IMHO, I see a lot of good in the report. For those interested, the results are copied below and entire report linked here: www.redjournal.org/article/S0360-3016(16)33598-2/fulltext

Results

The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P<.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P<.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02).

Facanating!

Thanks Tall Allen and Notam. I will continue to monitor and learn just in case I require radiation some day.