Yippee another Spacer trial

[Chartreuse Wombat]

Hyaluronic Acid Spacer for Hypofractionated Prostate Radiation Therapy

This randomized clinical trial examines whether a hyaluronic acid rectal spacer could improve rectal dosimetry and affect acute grade 2 or higher gastrointestinal toxic effects for hypofractionated radiation therapy.

jamanetwork.com

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[RickyScott]

Hyaluronic Acid Spacer for Hypofractionated Prostate Radiation Therapy

This randomized clinical trial examines whether a hyaluronic acid rectal spacer could improve rectal dosimetry and affect acute grade 2 or higher gastrointestinal toxic effects for hypofractionated radiation therapy.

jamanetwork.com

I know this is hypofrac, but there is now way that 10% of 1.8/79gy pts experience g2 or greater rectal toxcity

 

[elementaryschooleconomics]

First author:
$111,000 from Boston Scientific
$6,500 from Augmenix

Second author:
$292,000 from Boston Scientific
$213,000 from Augmenix
$255,000 from Palette

Rounding the dollar amount, not counting research funding - which is a lot more. Wonder what the COI looks like:

Let's take a look at the paper:

Uh ok, so the PTV could almost double in size from one patient to the next? I'm glad the posterior margin was held constant, but when your primary endpoint is some arbitrary DVH measurement...well, you could see a "significant reduction" in the rectal dose by just using a 1-2mm smaller PTV.

There's no way that the physicians used tighter margins and more strict planning in this unblinded, industry-funded study?

No, of course not!

Let's see what information they give us about plan quality:

[image not found]

Oh. Ok. Nothing.

I'm excited to see what mind-blowing, clinically-relevant results they're reporting:

Wait. The primary endpoint was "at least" a 25% reduction in rectum V54...and that was "significantly higher than the minimally acceptable rate of 70%"???

So the V54 went from a mean from 9.2% - with a standard deviation of 4% and range of 2% to 23% - to 1.5% with a standard deviation of 2.3% and a range of 0 to 18%...and that's....good?

Who in the world decided this 25% reduction in the V54 like...mattered...at all?

Going down the rabbit hole (because this cited work uses this endpoint citing earlier work), we arrive here:

A 2006 paper comparing 3D with IMRT. Yes. Of course. Totally makes sense.

Wait, what's this figure I see?

Oh cool. If you shrink the average PTV margin by just 2mm, you can obviously see the DVH shift down. Because of course you can.

I wonder what the patients themselves reported:

AT SIX MONTHS, THE PATIENT'S SELF-REPORTED SYMPTOMS WERE VIRTUALLY IDENTICAL.

Great work. Really great stuff.

 

[radoncftw]

First author:
$111,000 from Boston Scientific
$6,500 from Augmenix

Second author:
$292,000 from Boston Scientific
$213,000 from Augmenix
$255,000 from Palette

Rounding the dollar amount, not counting research funding - which is a lot more. Wonder what the COI looks like:

View attachment 365806

Let's take a look at the paper:

View attachment 365794

Uh ok, so the PTV could almost double in size from one patient to the next? I'm glad the posterior margin was held constant, but when your primary endpoint is some arbitrary DVH measurement...well, you could see a "significant reduction" in the rectal dose by just using a 1-2mm smaller PTV.

There's no way that the physicians used tighter margins and more strict planning in this unblinded, industry-funded study?

No, of course not!

Let's see what information they give us about plan quality:

[image not found]

Oh. Ok. Nothing.

I'm excited to see what mind-blowing, clinically-relevant results they're reporting:

View attachment 365807

Wait. The primary endpoint was "at least" a 25% reduction in rectum V54...and that was "significantly higher than the minimally acceptable rate of 70%"???

View attachment 365808

So the V54 went from a mean from 9.2% - with a standard deviation of 4% and range of 2% to 23% - to 1.5% with a standard deviation of 2.3% and a range of 0 to 18%...and that's....good?

Who in the world decided this 25% reduction in the V54 like...mattered...at all?

View attachment 365809

View attachment 365810

Going down the rabbit hole (because this cited work uses this endpoint citing earlier work), we arrive here:

View attachment 365811

A 2006 paper comparing 3D with IMRT. Yes. Of course. Totally makes sense.

Wait, what's this figure I see?

View attachment 365812

Oh cool. If you shrink the average PTV margin by just 2mm, you can obviously see the DVH shift down. Because of course you can.

I wonder what the patients themselves reported:

View attachment 365813

AT SIX MONTHS, THE PATIENT'S SELF-REPORTED SYMPTOMS WERE VIRTUALLY IDENTICAL.

Great work. Really great stuff.

Primary endpoint was a DVH metric. How did this make it into Jama Onc? I guess it was a randomized trial, but wow.

 

[WanderingRad3]

I know this is hypofrac, but there is now way that 10% of 1.8/79gy pts experience g2 or greater rectal toxcity

Grade 2 toxicity is not 10% in your experience?
CHIPP suggests >25%

5-12% late tox in this trial (less in conventional fx): Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer

Not very impressed with the magnitude of impact, but this trial reinforces my typical practice of hypofx + spacing as the most cost-effective/patient centric option (I still do conventional fx for some who would rather minimize acute symptoms and have all the time in the world + don’t do spacing for folks who don’t want a TRUS/needles for spacing).

Still personally prefer SpaceOAR because it’s iodinated vs Barrigel

Disclosure: no funding from either spacing company but I do generate more RVUs when I conventionally fractionate or space (or both)

 

[medgator]

 

[NotMattSpraker]

Grade 2 toxicity is not 10% in your experience?
CHIPP suggests >25%

5-12% late tox in this trial (less in conventional fx): Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer

Not very impressed with the magnitude of impact, but this trial reinforces my typical practice of hypofx + spacing as the most cost-effective/patient centric option (I still do conventional fx for some who would rather minimize acute symptoms and have all the time in the world + don’t do spacing for folks who don’t want a TRUS/needles for spacing).

Still personally prefer SpaceOAR because it’s iodinated vs Barrigel

Disclosure: no funding from either spacing company but I do generate more RVUs when I conventionally fractionate or space (or both)

I have the same problem with this trial as I did with the last one. There is a small and significant effect, but I do not think it is clinically relevant for most people. The author's know this and that makes it a lot worse for me. They play statistical games and use language that is misleading. I understand the logic of using an end point "grade 2+ toxicity", but in my opinion they should explicitly say in the text that there was only 1 grade 3 toxicity in the whole study.

I do not use fiducials or spacer for conventional or hypofractionated radiotherapy and get an MRI, so the baseline in my clinic is no uncomfortable/"invasive" procedure at all. If I was pitching this, I would have to say to patients "you can have this procedure and your chance of needing (example) steroid suppository for a few months will go from 14% to 2%". I would have to tell them about the post market toxicity data for the placement procedure. Personally, I would not take that deal and I would tell them that too. People usually ask what I would do. I'd also have to tell them that they can have conventionally fractionated radiotherapy with no invasive procedure and have lower toxicity as well.

Id have to tell them there is no difference in QoL.... we think. In modern studies, patient reported toxicity tends to be greater than physician reported toxicity. This makes me worry about bias since this study was not blinded. By leaving out post-procedure, mid-treatment, and post-treatment QoL time points, most of the toxicity could have came and went before the first interventional QoL inventory was offered. Admittedly, this data would have been interesting.

You could put some of these ideas in the discussion, but instead they have phrases like this: "We found that a numerically smaller (26.5% vs 37.7%; P = .13) percentage of patients in the spacer group experienced a bowel MCID at 3 months. This difference may have not reached statistical difference, due to lack of power."

Bro. Bro. Come on. You chose your end point. Stop.

Discussion of PTV margins is conspicuously absent. They are larger than I use so Im left wondering if any of this is even relevant to me.

All of this is just so dishonest. It's very difficult to take this study team seriously.

 

[BobbyHeenan]

I have the same problem with this trial as I did with the last one. There is a small and significant effect, but I do not think it is clinically relevant for most people. The author's know this and that makes it a lot worse for me. They play statistical games and use language that is misleading. I understand the logic of using an end point "grade 2+ toxicity", but in my opinion they should explicitly say in the text that there was only 1 grade 3 toxicity in the whole study.

I do not use fiducials or spacer for conventional or hypofractionated radiotherapy and get an MRI, so the baseline in my clinic is no uncomfortable/"invasive" procedure at all. If I was pitching this, I would have to say to patients "you can have this procedure and your chance of needing (example) steroid suppository for a few months will go from 14% to 2%". I would have to tell them about the post market toxicity data for the placement procedure. Personally, I would not take that deal and I would tell them that too. People usually ask what I would do. I'd also have to tell them that they can have conventionally fractionated radiotherapy with no invasive procedure and have lower toxicity as well.

Id have to tell them there is no difference in QoL.... we think. In modern studies, patient reported toxicity tends to be greater than physician reported toxicity. This makes me worry about bias since this study was not blinded. By leaving out post-procedure, mid-treatment, and post-treatment QoL time points, most of the toxicity could have came and went before the first interventional QoL inventory was offered. Admittedly, this data would have been interesting.

You could put some of these ideas in the discussion, but instead they have phrases like this: "We found that a numerically smaller (26.5% vs 37.7%; P = .13) percentage of patients in the spacer group experienced a bowel MCID at 3 months. This difference may have not reached statistical difference, due to lack of power."

Bro. Bro. Come on. You chose your end point. Stop.

Discussion of PTV margins is conspicuously absent. They are larger than I use so Im left wondering if any of this is even relevant to me.

All of this is just so dishonest. It's very difficult to take this study team seriously.

...and unless I read it wrong, the only G3 toxicity was in the spaceOAR group, not the control group.

Also we've joked about this before, but how do you grade the toxicity of a needle in the taint?

Is that 100% grade 1 toxicity in that arm?

I do spaceOAR (though increasingly it's the urologists placing) and offer it and have discussions as above. After a few scares with rectal wall infiltration (not by me - thankfully everything went fine) and further review of the literature I just don't push it too much. Not sure how much it helps in the vast majority of patients.

 

[NotMattSpraker]

...and unless I read it wrong, the only G3 toxicity was in the spaceOAR group, not the control group.

Also we've joked about this before, but how do you grade the toxicity of a needle in the taint?

Is that 100% grade 1 toxicity in that arm?

I do spaceOAR (though increasingly it's the urologists placing) and offer it and have discussions as above. After a few scares with rectal wall infiltration (not by me - thankfully everything went fine) and further review of the literature I just don't push it too much. Not sure how much it helps in the vast majority of patients.

You did not read it wrong, but I would just disregard it. They talked about the case in the text, seems like a patient with extraordinary sensitivity to radiation. We've all had them.

We just talked about spacers in our new practice. I have no problem with someone wanting to do it, it's just hard to be motivated to start doing spacer given the data. The group agreed. There are easier ways to increase revenue that are also better for patients.

 

[imhopeful432]

Hyaluronic Acid Spacer for Hypofractionated Prostate Radiation Therapy

This randomized clinical trial examines whether a hyaluronic acid rectal spacer could improve rectal dosimetry and affect acute grade 2 or higher gastrointestinal toxic effects for hypofractionated radiation therapy.

jamanetwork.com

You did not read it wrong, but I would just disregard it. They talked about the case in the text, seems like a patient with extraordinary sensitivity to radiation. We've all had them.

We just talked about spacers in our new practice. I have no problem with someone wanting to do it, it's just hard to be motivated to start doing spacer given the data. The group agreed. There are easier ways to increase revenue that are also better for patients.

Also the truth is that it doesn't pay a lot in most localities. I think it costs $2800 or so to acquire, $3100 or so reimbursement in the Colorado area (if billing globally). Or 3 RVUs.

So I don't know how many people are doing it purely to boost revenue (I imagine there are more lucrative procedures for the time spent for most rad oncs and urologists).

 

[OTN]

Just had a spacer explode 3 weeks into treatment. The patient was uncomfortable.
View attachment 365856View attachment 365856

Did you report it into their AE system?

 

[RickyScott]

Did you report it into their AE system?

No it just happened.

 

[Gfunk6]

How can a SpaceOAR explode?

 

[BobbyHeenan]

No it just happened.

MRI imaging?

I wonder if that splayed out the layers of hte rectal wall?

 

[Mandelin Rain]

This business model seems to be "make as much cash as possible before everyone inevitably has a single terrible outcome and reviews the data for why they actually do this to people."

 

[medgator]

How can a SpaceOAR explode?

Probably infiltrated into wall and turned into an abscess. Would be very cautious regarding infection/abscess risk @RickyScott my patients gel, placed by gu, ended up requiring elective colostomy with symptoms similar to that at the end of tx

 

[RickyScott]

Probably infiltrated into wall and turned into an abscess. Would be very cautious regarding infection/abscess risk @RickyScott my patients gel, placed by gu, ended up requiring elective colostomy with symptoms similar to that at the end of tx

I put him on cipro for 2 weeks and the collection seemed to resolve and now he is no longer symptomaticz

 

[xrt123]

IS SDN better then their AE system? Seems like someone needs to copy and paste this thread to the FDA.

 

[OTN]

IS SDN better then their AE system? Seems like someone needs to copy and paste this thread to the FDA.

SDN is better than the Red Journal for radonc data at this point

 

[elementaryschooleconomics]

Yeah so...I think there can be only two possibilities:

1) World-record level of fiber intake

2) Vigorous foreign body application to the rectal vault

Or, actually:

3) Both

 

[BobbyHeenan]

Placement (by urology) was fine. Here it is at the time of sim one week after insertion.

I would still get an MRI. But you're right, that does look free and clear and a reasonable placement.

Would also have a good surg onc that does proctos take a look at mucosa and make sure no ulcer or abnormality.

The Neal Desai case report article on the spaceOAR disaster case is really helpful. For possible rectal wall infiltration they get MRI and procto.

 

[BobbyHeenan]

Sometimes patient have a prominent "rectal hump" in that bend of the rectum at the anorectal junction. The reps will train you to take needle through the hump and into the space. in theory if that needle dives through dirty rectal mucosa then into space you can seed infection there. So your flash of saline hydrodissection looks great, placement looks great, but to the get needle in the space you had to take it through rectal wall. I've had a case like that. Didn't get infection but I did not feel good about how I had to put the needle to get it into the space.

 

[Pointless]

I don't get the reaction to spacer placement on this board. We do SpaceOAR in our practice, it goes well, and our guys seem to do very well with hypofrac or SBRT. It's not for money (it reimburses very little), it just seems like the right thing to do. It makes logical sense that increased distance = lower rectal dose = lower toxicity. As a secondary benefit, you can also push harder on the bladder to lower the dose there as well. Are there data suggesting inferior outcomes with SpaceOAR or what am I missing here??

 

[evilbooyaa]

@RickyScott when I saw your first pic I was going to post "Rectal wall infiltratioN?!" but the second pic does look... fine. Maybe an infection/abscess. Agree with Scope r/o mucosal changes before you just continue the beam.

Sometimes patient have a prominent "rectal hump" in that bend of the rectum at the anorectal junction. The reps will train you to take needle through the hump and into the space. in theory if that needle dives through dirty rectal mucosa then into space you can seed infection there. So your flash of saline hydrodissection looks great, placement looks great, but to the get needle in the space you had to take it through rectal wall. I've had a case like that. Didn't get infection but I did not feel good about how I had to put the needle to get it into the space.

I do place SpaceOARs for SBRT or at patient request, and I would not stick a needle through rectal hump. My local rep does not recommend I put a needle through the rectal hump. You can get up and over and then bend the needle into the space necessary. The reps think you can't but you can even get over the hump and flatten the rectum out. Also, leg positioning with hips in less tension (meaning legs closer to patient midline) with knees at 90 degrees can flatten out a rectal hump, even once US probe is.

 

[RickyScott]

@RickyScott when I saw your first pic I was going to post "Rectal wall infiltratioN?!" but the second pic does look... fine. Maybe an infection/abscess. Agree with Scope r/o mucosal changes before you just continue the beam.



I do place SpaceOARs for SBRT or at patient request, and I would not stick a needle through rectal hump. My local rep does not recommend I put a needle through the rectal hump. You can get up and over and then bend the needle into the space necessary. The reps think you can't but you can even get over the hump and flatten the rectum out. Also, leg positioning with hips in less tension (meaning legs closer to patient midline) with knees at 90 degrees can flatten out a rectal hump, even once US probe is.

I gave pt 2 week break w/abx and the mass resolved. (He is on hormones). Surgeon did not want to instrument the rectum.

 

[elementaryschooleconomics]

I don't get the reaction to spacer placement on this board. We do SpaceOAR in our practice, it goes well, and our guys seem to do very well with hypofrac or SBRT. It's not for money (it reimburses very little), it just seems like the right thing to do. It makes logical sense that increased distance = lower rectal dose = lower toxicity. As a secondary benefit, you can also push harder on the bladder to lower the dose there as well. Are there data suggesting inferior outcomes with SpaceOAR or what am I missing here??

1) "Our guys seem to do very well with hypofrac or SBRT"

Ok...compared to what? I virtually never use the gel and my patients also do very well. There were many years after the widespread adoption of CBCT/VMAT but before SpaceOAR where I'm pretty sure literally millions of guys were cured of prostate cancer without alarming toxicity.

2) "It's not for the money"

While the doctor pockets very little, the cost to the patient is significantly higher. This is hidden very well in academia, which is unfortunate, given many of us are first exposed to the gel in residency. If the procedure is not covered by the patient's insurance, they're on the hook for $4,000-$6,000. There is often a second MRI to verify placement, which can also range into the thousands of dollars for out-of-pocket expenses. SpaceOAR/Barrigel is hands-down one of the most financially toxic things we inflict on patients.

3) "It makes logical sense..."

Well, as this paper itself literally shows...this defies logic, then, as the lower rectal dose DOES NOT TRANSLATE TO LOWER PATIENT-REPORTED TOXICITY.

4) "Are there data suggesting inferior outcomes"

Well, considering almost every paper ever published about SpaceOAR or Barrigel has COI, with either personal fees, ownership interest, or research funding...it almost appears as if Augmenix, Boston Scientific, and Palette Life Sciences have managed to get into the pockets of every American RadOnc who would have the resources and motivation to conduct such a study. Weird, right?

Think of how many RadOncs have either trained under, or have their paychecks affected by, people like Peter Orio (Vice Chair of Network Operations, Brigham), Michael Zelefsky (Endowed Vice Chair, Sloan), and Paul Nguyen (GU Director and Vice Chair, Dana-Farber).

From OpenPayments:

Almost $3 million dollars paid out before being bought by Boston Scientific. And now we have Palette in the game!

5) "What am I missing here?"

Using the gel:
- is a procedure that "solves" a problem which didn't exist in the first place
- puts the patient at risk of adverse reaction to the medications used during the procedure
- puts the patient at risk of injury, infection, and bleeding
- puts the patient at risk of experiencing significant financial toxicity
- puts the patient at risk by inducing complications which prohibit completing definitive therapy
- puts the patient at risk of permanent complications
- contributes to the erosion of public trust by engaging in practice patterns influenced by millions of dollars in industry payments

This really seems like the right thing to do?

 

[Pointless]

Using the gel:
- is a procedure that "solves" a problem which didn't exist in the first place
- puts the patient at risk of adverse reaction to the medications used during the procedure
- puts the patient at risk of injury, infection, and bleeding
- puts the patient at risk of experiencing significant financial toxicity
- puts the patient at risk by inducing complications which prohibit completing definitive therapy
- puts the patient at risk of permanent complications
- contributes to the erosion of public trust by engaging in practice patterns influenced by millions of dollars in industry payments

This really seems like the right thing to do?

Radiation proctitis is a problem that doesn't exist? As for the bleeding, infection, risk, etc, do you take the same stance on fiducial marker placement? What if the SpaceOAR is placed without general anesthesia?

I've never had a patient get hit with an unexpected charge for this and, if they did, our department would eat it as is our practice. SpaceOAR vue has contrast in the gel and thus a second MRI is not necessary.

I have yet to see an adverse event as a result of a gel placement (though I'm sure if we do enough of them I will see one), so I suppose you have a point there; though again, if you don't summarily dismiss the randomized data, there are likely more adverse events (grade 2+ 5% vs 0% from the Hamstra study) from not using the gel then using it.

Contributes to erosion of public trust? Come on, man. You obviously have a stance that you've taken here, but... possibly a wee bit of hyperbole?

 

[elementaryschooleconomics]

Radiation proctitis is a problem that doesn't exist? As for the bleeding, infection, risk, etc, do you take the same stance on fiducial marker placement? What if the SpaceOAR is placed without general anesthesia?

I've never had a patient get hit with an unexpected charge for this and, if they did, our department would eat it as is our practice. SpaceOAR vue has contrast in the gel and thus a second MRI is not necessary.

I have yet to see an adverse event as a result of a gel placement (though I'm sure if we do enough of them I will see one), so I suppose you have a point there; though again, if you don't summarily dismiss the randomized data, there are likely more adverse events (grade 2+ 5% vs 0% from the Hamstra study) from not using the gel then using it.

Yes, I don't use fiducials either. Just daily CBCT. For the same reasons.

I don't mean general - I think most of us use PO meds, yes? I had a patient experience an adverse reaction to Ativan prior to the procedure in my lobby. (He's fine now)

As per the recent MedNet discussion, there seems to be a large number of people doing a second MRI with VUE.

I have personally witnessed adverse events of gel placement. To be clear, it's definitely NOT common. I would say no more than a 1% adverse event rate...which is still significantly more than the event rate in patients without the gel.

Yes, I clearly fall on one side of this debate. Because of where I trained and then the institutions where I have practiced/currently practice, I have significantly more first-hand experience with the hydrogel than most people.

If my opinion seems hyperbolic to you, it's only because I've seen and done this more.

 

[salubalu]

How can a SpaceOAR explode?

It’s the new spaceoar bang

 

[salubalu]

I don't get the reaction to spacer placement on this board. We do SpaceOAR in our practice, it goes well, and our guys seem to do very well with hypofrac or SBRT. It's not for money (it reimburses very little), it just seems like the right thing to do. It makes logical sense that increased distance = lower rectal dose = lower toxicity. As a secondary benefit, you can also push harder on the bladder to lower the dose there as well. Are there data suggesting inferior outcomes with SpaceOAR or what am I missing here??

Part of me wonders if some individuals are biased because they do not want to do the procedure. #nottryingtohate

 

[deleted1111261]

Putting a patient under and inserting a needle through perineum has to rate as a toxicity if we are going to count giving flomax or Imodium as significant.

As for late toxicity, grade 2-3 for GU/GI on PACE B is 2-3%. Spacer is not going to make much of a dent.

I don’t use fiducials. Good prep + CBCT, plus being around the Linac and not giving RTTs hell for low threshold for my eyes is enough. I use @OTN approach (good prep/sim, no spacer, no fiducials, aggressive OAR restriction).

Solution in search of a problem is how I see it. The studies used statistical chicanery and I cannot believe the second one was in JAMA Onc. I guess it’s better than what the Red Journal puts out, but just barely.

 

[salubalu]

Putting a patient under and inserting a needle through perineum has to rate as a toxicity if we are going to count giving flomax or Imodium as significant.

As for late toxicity, grade 2-3 for GU/GI on PACE B is 2-3%. Spacer is not going to make much of a dent.

I don’t use fiducials. Good prep + CBCT, plus being around the Linac and not giving RTTs hell for low threshold for my eyes is enough. I use @OTN approach (good prep/sim, no spacer, no fiducials, aggressive OAR restriction).

Solution in search of a problem is how I see it. The studies used statistical chicanery and I cannot believe the second one was in JAMA Onc. I guess it’s better than what the Red Journal puts out, but just barely.

What do y’all make Pace b showing better side effect profile with cyberknife SBRT vs linac SBRT?😛

 

[radonc17]

Why would a SpaceOAR trial use non-inferiority as a toxicity endpoint?

If you’re undergoing invasive procedure shouldn’t it be superior??

Unless they are accounting for the side effects from the procedure itself?

Which defeats the purpose….

 

[sirspamalot]

Ju$t pure non$en$e and a ca$h grab using the gel. Extra risk, minimal value, but oh that sweet sweet moola. Ethically challenged procedure at this point.

So, for all those thousands of patients who got the ultra-hypofractionation of seed implant.. and before gel existed... and with good implants.. did fine.. sorry, what was the point again?

But of course, if you have to ask, the answer is always the same isn't it..

 

[salubalu]

$ makes the world turn no?

 

[medgator]

Radiation proctitis is a problem that doesn't exist? As for the bleeding, infection, risk, etc, do you take the same stance on fiducial marker placement?

Yes, I don't use fiducials either. Just daily CBCT. For the same reasons.

I don't mean general - I think most of us use PO meds, yes? I had a patient experience an adverse reaction to Ativan prior to the procedure in my lobby. (He's fine now)

As per the recent MedNet discussion, there seems to be a large number of people doing a second MRI with VUE.

I have personally witnessed adverse events of gel placement. To be clear, it's definitely NOT common. I would say no more than a 1% adverse event rate...which is still significantly more than the event rate in patients without the gel.

Yes, I clearly fall on one side of this debate. Because of where I trained and then the institutions where I have practiced/currently practice, I have significantly more first-hand experience with the hydrogel than most people.

If my opinion seems hyperbolic to you, it's only because I've seen and done this more.

Placed fiducials for over a decade via TRUS and never saw patients getting infections/complications leading to the need for weeks of IV abx or elective colostomy.

Fiducials were placed for years prior to spaceOAR ever being on the market and we did fine with ultra-tight PTV margins esp posteriorly in terms of long-term rectal toxicity precisely because we had that confidence via implanted fiducials. People feel the same now with daily CBCT, I guess it's fine if you have well-trained therapists, but some of the data out there suggests kV with fiducials probably more accurate and reproducible even at a physician level, if you combine with CBCT you get the best of both worlds and some choose to do that, as the fiducials give more confidence to the match, either via CT or kV match

2D kV orthogonal imaging with fiducial markers is more precise for daily image guided alignments than soft-tissue cone beam computed tomography for prostate radiation therapy

The hypothesis is that 2-dimensional kV orthogonal imaging with fiducial markers (kV-FM) and soft-tissue cone beam computed tomography (ST-CBCT) are equally reproducible for daily positional alignments for image guided (IG) intensity modulated radiation ...

www.ncbi.nlm.nih.gov

Daily patient setup error in prostate image guided radiation therapy with fiducial-based kilovoltage onboard imaging and conebeam computed tomography - PubMed

The residual setup errors following daily kV image guided localization, as determined by CBCT, were small, which demonstrates high accuracy of kV localization when fiducial markers are present.

pubmed.ncbi.nlm.nih.gov

 

[elementaryschooleconomics]

Placed fiducials for years via TRUS transrectally and never saw patients getting infections/complications leading to the need for weeks of IV abx or elective colostomy. Fiducials were placed for years prior to spaceOAR ever being on the market and we did fine with ultra-tight PTV margins esp post in terms of long-term toxicity precisely because we had that confidence via implanted fiducials. People feel the same now with daily CBCT, I guess it's fine if you have well-trained therapists, but some of the data out there suggests kV with fiducials probably more accurate and reproducible even at a physician level, if you combine with CBCT you get the best of both worlds and some choose to do that, as the fiducials give more confidence to the match, either via CT or kV match

Ah, yeah - this goes down a whole different rabbit hole.

You were (are?) doing the fiducials yourself, yes? I assume you can probably do the entire procedure in less than 20 minutes?

RadOncs with a high volume/long history of fiducial placement are in a league of their own. I started dipping my toes in the "no fiducial" water because of difficulties in coordinating with Urology, and as time went on, I wasn't seeing any difference, and I started questioning the practice, yadda yadda - no fiducials is now my standard practice.

I'm familiar with those papers, and have some people in my real-life orbit who like to debate this with me every other month or so, and I never make my PTV expansions <5mm if I don't have fiducials as a result. For you cowboys with your 3mm or 4mm margins...yeah, I'd probably go with fiducials for that.

 

[medgator]

Ah, yeah - this goes down a whole different rabbit hole.

You were (are?) doing the fiducials yourself, yes? I assume you can probably do the entire procedure in less than 20 minutes?

RadOncs with a high volume/long history of fiducial placement are in a league of their own. I started dipping my toes in the "no fiducial" water because of difficulties in coordinating with Urology, and as time went on, I wasn't seeing any difference, and I started questioning the practice, yadda yadda - no fiducials is now my standard practice.

I'm familiar with those papers, and have some people in my real-life orbit who like to debate this with me every other month or so, and I never make my PTV expansions <5mm if I don't have fiducials as a result. For you cowboys with your 3mm or 4mm margins...yeah, I'd probably go with fiducials for that.

Yep, started placing fiducials and giving ADT as soon as i left residency. Out IRL, patients just show up with a path report and need treatment and many urologists aren't interested/can't be bothered with trus fiducial placement, eligard or both, esp since the heyday of sick lupron margins from the 90s is long gone

You hire an US tech who brings the machine and can generally do the procedure in a few minutes (<10 I'd guess), I've had n=1 end up in the hospital with a uti during my years of doing it, which is why what i saw with spaceoar, AE wise, was just mind-blowing. Transperineal placement is technically "cleaner" but obviously more complex and not as quick with more room for complications being in that space.

Fiducials help me sleep better at night, kV or cbct match to them is virtually idiot-proof at the console. I still see the occasional pt on long term blood thinners s/p recent ptca/stent or mechanical valve that isn't cleared by cards to come off anticoagulation so we do cbct in those cases and i make sure the therapists feel comfortable with it in those cases. And yeah if you are doing 4-5mm rectal margins to begin with, what exactly did spaceOAR bring to the table?

 

[WanderingRad3]

I don’t do second MRI after and use SpaceOAR Vue. I don’t do oral meds (just local lidocaine, for 95%+ patients).

I tell my patients not to pay OOP for the rare insurance that does not cover it. But I personally would pay $5000 OOP for spaceoar for me and my dad if I were getting radiation for prostate cancer (I realize I’m a privileged attending rad Onc thar has the disposable income to do so).

I think the benefit is real but small. I think most docs make very little $ off this procedure. The harsh criticism (after 2 RCTs) for something that is less financially toxic than most things we do with less data (calypso, protons, 44 fractions, etc) is bizarre to me….

 

[WanderingRad3]

But then again, if going purely by the data, we should not be doing daily CBCT… www.thegreenjournal.com/article/S0167-8140(17)32680-4/fulltext

As that study shows, pretty hard to show a statistically significant difference! So I tend to believe spaceoar/mirage/Barrigel

 

[sirspamalot]

"So I tend to believe spaceoar/mirage/Barrigel" .. does what exactly? This reminds me of the proton thread..

The cited study technique may explain why little difference was seen between the arms "Using a four-field box technique with necessary supplemental field segments, 15 megavolt (MV) photon beams from 0 to 70 Gy were applied."

Also, was there any follow up paper to this one? I looked briefly for it.. and didn't find it. Perhaps longer term follow up might have demonstrated a difference...probably not though.

Anyhoo there is no doubt that 'less' overall rectal volume is better than 'more' (low or high dose) and the community standard is CBCT alone. I've never used fiducials or gel, and probably won't.

One can argue that relying on fiducials alone (some do at urorad centers with older non-CBCT equipped linacs and too bu$y to shut down and upgrade) is not ideal unless treating only prostate..

 

[medgator]

"So I tend to believe spaceoar/mirage/Barrigel" .. does what exactly? This reminds me of the proton thread..

The cited study technique may explain why little difference was seen between the arms "Using a four-field box technique with necessary supplemental field segments, 15 megavolt (MV) photon beams from 0 to 70 Gy were applied."

Also, was there any follow up paper to this one? I looked briefly for it.. and didn't find it. Perhaps longer term follow up might have demonstrated a difference...probably not though.

Anyhoo there is no doubt that 'less' overall rectal volume is better than 'more' (low or high dose) and the community standard is CBCT alone. I've never used fiducials or gel, and probably won't.

One can argue that relying on fiducials alone (some do at urorad centers with older non-CBCT equipped linacs and too bu$y to shut down and upgrade) is not ideal unless treating only prostate..

I've heard of several prostate only centers upgrading/switching over to a halcyon.... Imrt/vmat workhorse

 

[BobbyHeenan]

So to put this in patient language for counseling, you can say the gel will reduce the chance you may need Imodium during treatment from 14% to 2%? Is that a correct way to frame it?

I’m most interested as a doc in the late bleeding risk from xrt. But I don’t see that shaking out in this paper - though only 6 months follow up.

 

[sirspamalot]

So to put this in patient language for counseling, you can say the gel will reduce the chance you may need Imodium during treatment from 14% to 2%? Is that a correct way to frame it?

I’m most interested as a doc in the late bleeding risk from xrt. But I don’t see that shaking out in this paper - though only 6 months follow up.

All for the small small risk of permanent rectal injury. Noice.

 

[salubalu]

I wonder if the dose fall of will translate into less secondary rectal cancer risk?

 

[BobbyHeenan]

I wonder if the dose fall of will translate into less secondary rectal cancer risk?

Certainly possible, but that rate is already low, so showing that would take many many patients on a trial. I dont think that’s a strong reason for the gel.

To me the best reason is to prevent the late bleeding. I have a hand full of guys that have had a hard time with late bleeding like many years after xrt. I have looked at their DVHs and alignment and never found anything weird. It still haunts you though. Or at least it does me. Just a thing that happens and almost always in patients on anti coagulation.

I’ve said it before but I think it is very valuable to see your prostate patients at least once every 12-18 months even many years later.

 

[elementaryschooleconomics]

I don’t do second MRI after and use SpaceOAR Vue. I don’t do oral meds (just local lidocaine, for 95%+ patients).

I tell my patients not to pay OOP for the rare insurance that does not cover it. But I personally would pay $5000 OOP for spaceoar for me and my dad if I were getting radiation for prostate cancer (I realize I’m a privileged attending rad Onc thar has the disposable income to do so).

I think the benefit is real but small. I think most docs make very little $ off this procedure. The harsh criticism (after 2 RCTs) for something that is less financially toxic than most things we do with less data (calypso, protons, 44 fractions, etc) is bizarre to me….

1) Excellent, I agree with you about the VUE MRI. However, in the MedNet poll about this (theMednet), with over 200 responses, 40% of RadOncs said they were still doing the second MRI.

2) Well, ok, but are you just saying "mission accomplished" after telling your patients a single time "don't pay for it"? Have you followed up a year or two later to see what happened?

I have been in SpaceOAR-heavy environments in both academia and private practice. In academia, they did an excellent job of keeping the docs "out of the money".

What you don't hear about is, years down the road, your institution suing these patients you're telling to not pay:

Thousands of Poor Patients Face Lawsuits From Nonprofit Hospitals That Trap Them in Debt

Across the country, low-income patients are overcoming stigmas surrounding poverty to speak out about nonprofit hospitals that sue them. Federal officials are noticing. Help us keep the pressure on.

www.propublica.org

They Were Entitled to Free Care. Hospitals Hounded Them to Pay. (Published 2022)

With the help of a consulting firm, the Providence hospital system trained staff to wring money out of patients, even those eligible for free care.

www.nytimes.com

Despite State Funding to Treat the Poor, NY’s Nonprofit Hospitals Filed More Than 30,000 Lawsuits Against Patients from 2015 to 2019

www.cssny.org

While there's no national policy for CMS, NGS has an LCD that has specific language stating patients must has low or favorable intermediate risk disease. In that LCD, they also cite commercial policy where the hydrogels are considered investigational.

While I've seen unfavorable intermediate and high risk get reimbursed despite this language, it gives payors a clear way out of paying.

3) I've never offered protons for prostate so I forget about it, but fair point, I imagine that is potentially more costly. Calypso has been sunset but I know for a fact the beacons are significantly cheaper than SpaceOAR (though more costly than gold, of course). The cost of 44 fractions (out-of-pocket, to the patient) varies widely depending on the institution and insurance. I know for a fact it's cheaper at my current hospital compared to hypofrac at a PPS-exempt center.

I can only speak for myself, but my statement about the financial toxicity for SpaceOAR stems from the fact that it is the only thing I've done that invoked an ABN for Medicare patients.

4) Sure, there have been two RCTs...

But they're garbage. The 2015 SpaceOAR trial only met one primary endpoint (the DVH reduction, a joke). My criticisms of this trial are in this thread (well, some of them, there are more coming). It's great that they were prospective RCTs. That's probably the only positive thing I can say.

Each of them were paid for by millions of dollars in both personal and research dollars.

You find this data compelling?

I wonder if the dose fall of will translate into less secondary rectal cancer risk?

Hahahaha - I can absolutely see Boston Scientific claiming this in future marketing materials.

 

[Pointless]

This just seems like a strange hill to die on. I made the switch after seeing the data from the Hamstra paper, which showed a decrease in grade 2 events in the long term analysis (and I believe increased QOL). It's a randomized control trial, which you are of course free to disregard, but I'm not sure how you can take the opposite stance with such certainty. Granted, I didn't do a deep dive into the COI's and such, so perhaps I'm missing something there.

The rectal and bladder DVH's are considerably better since I've been doing SpaceOAR than before (don't bother to ask if I've recorded, collated and performed the appropriate statistical analyses; I have not). If we don't believe DVH's matter, then why even look at them at all? I guess you could then use the same logic to defend protons with their better DVH and say why not that too? It would be a valid point, except there are no real randomized trials showing ANY benefit and possibly some suggestion of harm (both financially and medically). So a bit of a different issue.

I remain confused about the vehemence with which some people are against this. If you don't want to do it, fine. To suggest that offering it to your patients is some sort of malpractice or greedy money grab, that... is just strange. Somebody above posited that the people who don't want to do it are simply defending their stance by attacking the practice and this rings true to me. "I don't want to do it and so I'm actually a health care hero!!"

 

[WanderingRad3]

Here are the long term data:
“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).”

Continued Benefit to Rectal Separation for Prostate Radiation Therapy: Final Results of a Phase III Trial - PubMed

The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in...

pubmed.ncbi.nlm.nih.gov

 

[Pointless]

Here are the long term data:
“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).”

Continued Benefit to Rectal Separation for Prostate Radiation Therapy: Final Results of a Phase III Trial - PubMed

The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in...

pubmed.ncbi.nlm.nih.gov

The people who do this are BARBARIANS!