5x5 for spine mets

[Ray D. Ayshun]

Was googling for more shorter courses of palliative spine RT and noticed this recent pub from the god of palliative spine rt:

Comparison of 5 × 5 Gy and 10 × 3 Gy for metastatic spinal cord compression using data from three prospective trials - Radiation Oncology

Background In a palliative situation like metastatic spinal cord compression (MSCC), overall treatment time of radiotherapy should be as short as possible. This study compared 5 × 5 Gy in 1 week to 10 × 3 Gy in 2 weeks in a prospective cohort. Methods Forty patients receiving 5 × 5 Gy in a phase...

ro-journal.biomedcentral.com

I remember some recent posts on here where people said they were using 5x5 for palliative spine, or at least for cord compression. Is this becoming a common practice, and do you just use 5 fx sbrt constraints?

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[elementaryschooleconomics]

noticed this recent pub from the god of palliative spine rt

Is it sad I immediately said "DIRK RADES" to myself when I read this?

Nah, totally normal.

 

[FrostyHammer]

Was googling for more shorter courses of palliative spine RT and noticed this recent pub from the god of palliative spine rt:

Comparison of 5 × 5 Gy and 10 × 3 Gy for metastatic spinal cord compression using data from three prospective trials - Radiation Oncology

Background In a palliative situation like metastatic spinal cord compression (MSCC), overall treatment time of radiotherapy should be as short as possible. This study compared 5 × 5 Gy in 1 week to 10 × 3 Gy in 2 weeks in a prospective cohort. Methods Forty patients receiving 5 × 5 Gy in a phase...

ro-journal.biomedcentral.com

I remember some recent posts on here where people said they were using 5x5 for palliative spine, or at least for cord compression. Is this becoming a common practice, and do you just use 5 fx sbrt constraints?

I think we've talked about this sometime before in here - palex and I use 25/5 in place of 30/10 routinely. I barely ever do 30/10 anymore.

 

[RickyScott]

Was googling for more shorter courses of palliative spine RT and noticed this recent pub from the god of palliative spine rt:

Comparison of 5 × 5 Gy and 10 × 3 Gy for metastatic spinal cord compression using data from three prospective trials - Radiation Oncology

Background In a palliative situation like metastatic spinal cord compression (MSCC), overall treatment time of radiotherapy should be as short as possible. This study compared 5 × 5 Gy in 1 week to 10 × 3 Gy in 2 weeks in a prospective cohort. Methods Forty patients receiving 5 × 5 Gy in a phase...

ro-journal.biomedcentral.com

I remember some recent posts on here where people said they were using 5x5 for palliative spine, or at least for cord compression. Is this becoming a common practice, and do you just use 5 fx sbrt constraints?

Would assume 5 x5 volume includes the cord?

 

[medgator]

I think we've talked about this sometime before in here - palex and I use 25/5 in place of 30/10 routinely. I barely ever do 30/10 anymore.

3D?

 

[Palex80]

5 x 5 Gy is great. It's our basic palliative regime for everything more or less, when you want the treatment to be done fast and the prognosis is not good.

Metastatic primary in bladder or uterus and bleeding? 5 x 5 Gy, if there's not much bowel, top up with a 6th fraction.
Skin mets? 5 x 5 Gy
Metastatic H&N tumor with painful neck mass? 5-6 x 5 Gy
GBM in elderly who doesn't want BSC? 5 x 5 Gy

Would assume 5 x5 volume includes the cord?

Yes. No hotspots on cord, that's all (although I am "generous" in L-spine). When treating C-/T-spine, I like to limit dose to the esophagus too, for instance 5 x 4 Gy. If the mass is not sitting directly in the ventral part of the vertebra that's easy to do (not necessarily with IMRT/VMAT only).

3D?

VMAT.
We may only do 3D in super-super urgent cases that get consult, sim and first treatment within one day, since QA for VMAT takes half an hour longer or so. But even that is doable. Physics know that I will likely want a VMAT plan from fraction 2 onwards, so they are like "Oh, we'll plan with VMAT right away."

 

[Ray D. Ayshun]

5 x 5 Gy is great. It's our basic palliative regime for everything more or less, when you want the treatment to be done fast and the prognosis is not good.

Metastatic primary in bladder or uterus and bleeding? 5 x 5 Gy, if there's not much bowel, top up with a 6th fraction.
Skin mets? 5 x 5 Gy
Metastatic H&N tumor with painful neck mass? 5-6 x 5 Gy
GBM in elderly who doesn't want BSC? 5 x 5 Gy



Yes. No hotspots on cord, that's all (although I am "generous" in L-spine). When treating C-/T-spine, I like to limit dose to the esophagus too, for instance 5 x 4 Gy. If the mass is not sitting directly in the ventral part of the vertebra that's easy to do (not necessarily with IMRT/VMAT only).


VMAT.
We may only do 3D in super-super urgent cases that get consult, sim and first treatment within one day, since QA for VMAT takes half an hour longer or so. But even that is doable. Physics know that I will likely want a VMAT plan from fraction 2 onwards, so they are like "Oh, we'll plan with VMAT right away."

No problems with VMAT getting approved?

 

[drewdog1973]

He/she in Netherlands, i think. Probably payors dont care because people don’t misuse if there isn’t substantial differential between reimbursement between 3D and VMAT

question, @Palex80 - if doing conformal, maybe higher for pain control ? 30/5?

 

[Krukenberg]

He/she in Netherlands, i think. Probably payors dont care because people don’t misuse if there isn’t substantial differential between reimbursement between 3D and VMAT

question, @Palex80 - if doing conformal, maybe higher for pain control ? 30/5?

Hypo trial for advanced head/neck had good results with 30/5 +optional 6th fraction

 

[Palex80]

@Palex80 - if doing conformal, maybe higher for pain control ? 30/5?

Of course, you can give higher doses for pain control if you think the prognosis isn't disastrous. 5 x 5 Gy is mostly for really advanced cases in poor PS.

No problems with VMAT getting approved?

Welcome to Europe, where you get paid (more or less) the same irrelevant if it's VMAT or 3D!

He/she in Netherlands, i think.

Nope, not in the Netherlands. Netherlands don't need hypofractionation for pain control. They have other tricks.

 

[Ray D. Ayshun]

So does anybody do this 3D? Seems complicated to limit the cord to the constraints they mentioned, nvmd the esophagus. Conformal arcs?

 

[drewdog1973]

Of course, you can give higher doses for pain control if you think the prognosis isn't disastrous. 5 x 5 Gy is mostly for really advanced cases in poor PS.



Welcome to Europe, where you get paid (more or less) the same irrelevant if it's VMAT or 3D!




Nope, not in the Netherlands. Netherlands don't need hypofractionation for pain control. They have other tricks.
View attachment 331949

Sorry! I thought you were Dutch

 

[medgator]

Sorry! I thought you were Dutch

I think he may be German or Swiss iirc?

 

[FrostyHammer]

3D?

Yep. Max cord dose is 30 Gy for 5 fractions, so as long as the hotspot is <20% you're not hitting cord max.

 

[Ray D. Ayshun]

Yep. Max cord dose is 30 Gy for 5 fractions, so as long as the hotspot is <20% you're not hitting cord max

That's max point dose, but are there other constraints? BR-001, for instance, has a D22 of <0.35cc. Is simply saying hostpot <120% enough?

 

[FrostyHammer]

That's max point dose, but are there other constraints? BR-001, for instance, has a D22 of <0.35cc. Is simply saying hostpot <120% enough?

Well I try to use a max hotspot of 110% regardless of where it is, but 115% as an absolute cutoff. The Dmax values rarely come at the cord as well, they're mostly in the subQ fat and such. I only use absolute Dmax for 3d plans, versus for spine SBRT I use other volumetric ones because I can (since it's inverse planned). EQD-2 math works out too even with adjustments. There is no evidence that myelopathy is any more or less frequent if you just use a Dmax constraint versus Dmax plus others. NCCN's lung SBRT constraints only use an absolute Dmax without others. This is basically dealer's choice.

 

[TheWallnerus]

I guarantee you 5 times 4 Gy works just as good as 5 times 5 Gy in all the ways "works just as good" means within the realm of palliative medicine. Now... 4 times 5 Gy?! That one intrigues me

 

[Palex80]

I guarantee you 5 times 4 Gy works just as good as 5 times 5 Gy in all the ways "works just as good" means within the realm of palliative medicine. Now... 4 times 5 Gy?! That one intrigues me

I thought that's why you guys in the US introduced Palliative Radiotherapy FELLOWSHIPS for!

 

[Ray D. Ayshun]

It's would be easy enough to prove that no treatment is equivalent to 4GY x 5 with a 5 arm trial of fractions sizes 0, 1, 2, 3, and 4 Gy. In my limited experience, 4 Gy x 5 is kinda meh, while 5 x 5 seems to actually do something in other places. There's a line somewhere.

 

[TheWallnerus]

It's would be easy enough to prove that no treatment is equivalent to 4GY x 5 with a 5 arm trial of fractions sizes 0, 1, 2, 3, and 4 Gy. In my limited experience, 4 Gy x 5 is kinda meh, while 5 x 5 seems to actually do something in other places. There's a line somewhere.

I would love to argue that 5 x 4Gy is not different than 5 x 5Gy, but of course I can't. It'd just be an opinion war w/ someone. In one trial for bone mets e.g. 8 Gy/1 fx and 30/10 were different but had pluses/minuses respectively. In the real world, 8 Gy/1 fx came to be preferred obviously a lot of times despite some trade-offs. And 5 times 4 Gy may not be different than 30/10 palliation in some sites. Radiobiologically, 30/10 can be "stronger" than 25/5. (30 Gy is a hell of a lot "stronger" than 8 Gy in 1 fx.) There is nothing special about a 5 Gy fraction versus a 4 Gy fraction. To think otherwise is magical thinking. Thirty gray cures anal cancer (see the original Nigro e.g.). Thirty gray even cures big lung cancers. If I'm saying anything, I'm saying this: more dose and a bigger fraction size doesn't ALWAYS lead to more better patient outcomes and bigger physician satisfaction. Everything is two sided until you've well proven it's not.

 

[Ray D. Ayshun]

I would love to argue that 5 x 4Gy is not different than 5 x 5Gy, but of course I can't. It'd just be an opinion war w/ someone. In one trial for bone mets e.g. 8 Gy/1 fx and 30/10 were different but had pluses/minuses respectively. In the real world, 8 Gy/1 fx came to be preferred obviously a lot of times despite some trade-offs. And 5 times 4 Gy may not be different than 30/10 palliation in some sites. Radiobiologically, 30/10 can be "stronger" than 25/5. (30 Gy is a hell of a lot "stronger" than 8 Gy in 1 fx.) There is nothing special about a 5 Gy fraction versus a 4 Gy fraction. To think otherwise is magical thinking. Thirty gray cures anal cancer (see the original Nigro e.g.). Thirty gray even cures big lung cancers. If I'm saying anything, I'm saying this: more dose and a bigger fraction size doesn't ALWAYS lead to more better patient outcomes and bigger physician satisfaction. Everything is two sided until you've well proven it's not.

No doubt to all that wrt symptoms response. My goal here, though, is something quicker than ten fx that can be safely delivered with 3D planning while maximizing local control given the location of disease and complications of retreatment. I have no doubt 25 Gy in 5 has better local control than 20/5.

 

[drewdog1973]

Conformal Arcs are fantastic for palliation

 

[TheWallnerus]

No doubt to all that wrt symptoms response. My goal here, though, is something quicker than ten fx that can be safely delivered with 3D planning while maximizing local control given the location of disease and complications of retreatment. I have no doubt 25 Gy in 5 has better local control than 20/5.

You could be right. But local control is a very very very tricky metric to measure in a trial of palliative intent terminally ill patients. It’s even tougher to measure LC anecdotally from one’s own experiences. And we would also need to measure side effects and toxicity differences between doses in a palliative RT trial. “Trivial differences” are always trivial in the eye of the beholder.

 

[evilbooyaa]

1. I have never heard of Dirk Rades before. Feel like I'm missing something on 'god of palliative RT'.

2. I would only do 25/5 if I was doing it with VMAT to keep cord point dose < Rx dose. And TG101s, V23 < 0.35cc. And if I was already doing that, then why wouldn't I just do 30/5 (or higher as feasible) with the same constraint and call it SBRT? Conformal arcs may work but only if it's a very basic bone met without epidural extension or soft tissue component.

3. Do I really think 20/5 is way worse than 25/5? As long as the cord's tolerance to RT is not 100% burned with 25/5 then whatever. Maybe 20/4 is better and could be done 3D.

 

[Ray D. Ayshun]

God of palliative spine. You may not have heard of him, but you probably know his hits, including the scorad trilogy.

 

[Ray D. Ayshun]

The protocol on the trial i linked, btw, allow for max dose of 101.5%, which is to say the entirety of the cord within the PTV is getting 25 Gy. This, combined with some of the max point dose constraints from SBRT regimens makes me feel pretty comfortable with frostyhammer's approach, at least insofar as a dmax of 27.5 is concerned. Still not crazy about 30/5, though I'm curious to know the cord doses on 4 Gy x 5 PA only with 4 MV photons, which I'm sure has been done a lot.

 

[TheWallnerus]

You can give 25/5 to big sections of cord and it'll be safe. You can give 17 Gy in 2 fractions of 8.5 Gy apiece to big sections of cord and that's been proven safe. There has never been a regimen of any sort with <=100 BED Gy-2 that's been shown to be unsafe for the cord. There's a ~5% myelopathy risk, depending on what you may read, at 60 Gy in 30 fx which has a BED Gy-2 of 120. This is equivalent to 5 times 6 Gy. If the alpha/beta of cord is greater than 2 then 30 Gy in 5 fractions is even safer than a 5% myelopathy risk. (In residency I saw a not small cohort of H&N patients accidentally get ~60 Gy/30 fx to the c-spine and never saw a single case of clinical spinal cord toxicity. But that was at only 1 year followup or less.) In reality there's not a 0% myelopathy risk at 20/5, 25/5, or 30/10. Sometimes s**t happens. But s**t does seem to be dose dependent.

 

[Palex80]

Here is a 5 x 5 Gy VMAT plan for a big mass in the T-spine. Surgeons didn't want to intervene.

 

[TheWallnerus]

Here is a 5 x 5 Gy VMAT plan for a big mass in the T-spine. Surgeons didn't want to intervene.
View attachment 332076

Hypothetically...

To "the human eye" (and from the viewpoint of a post-tx CT, most likely), in the immediate post-tx period, 25/5 and 60/30 will give equal clinical responses. (But 25/5 will appear "zippier.") Assuming this was a garden-variety X-ray responding tumor, not too radiosensitive or radioresistant, i.e. a D-zero of 3 Gy, and this was a billion-cell mass... what is the estimated cell-killing effect (S.C.C. = surviving cell count) of 25/5 vs a much higher conventional fractionation dose?

S.C.C. 25/5 = ((e^(-5/3))^5)*1E9 = ~240,000 cells remain

S.C.C. 60/30 = ((e^(-2/3))^30)*1E9 = ~2 cells remain

So. 25/5 is nice. 60/30 would be nicer? "Local control" of this thing is probably wishful thinking no matter what, but 25/5 is more wishful than conventional fractionation to higher doses. Somehow, though, we've become enamored that 5 Gy fractions to low total cumulative doses is doing something that conventional fractionation to double, or more, total cumulative doses never did.

 

[Palex80]

Hypothetically...

To "the human eye" (and from the viewpoint of a post-tx CT, most likely), in the immediate post-tx period, 25/5 and 60/30 will give equal clinical responses. (But 25/5 will appear "zippier.") Assuming this was a garden-variety X-ray responding tumor, not too radiosensitive or radioresistant, i.e. a D-zero of 3 Gy, and this was a billion-cell mass... what is the estimated cell-killing effect (S.C.C. = surviving cell count) of 25/5 vs a much higher conventional fractionation dose?

S.C.C. 25/5 = ((e^(-5/3))^5)*1E9 = ~240,000 cells remain

S.C.C. 60/30 = ((e^(-2/3))^30)*1E9 = ~2 cells remain

So. 25/5 is nice. 60/30 would be nicer? "Local control" of this thing is probably wishful thinking no matter what, but 25/5 is more wishful than conventional fractionation to higher doses. Somehow, though, we've become enamored that 5 Gy fractions to low total cumulative doses is doing something that conventional fractionation to double, or more, total cumulative doses never did.

In theory, absolutely correct. We are treating another 3 sites (L-spine, pelvis) and there are even more, we aren't treating (yet). KPS is 60.

 

[TheWallnerus]

In theory, absolutely correct. We are treating another 3 sites (L-spine, pelvis) and there are even more, we aren't treating (yet). KPS is 60.

Was googling for more shorter courses of palliative spine RT and noticed this recent pub from the god of palliative spine rt:

Comparison of 5 × 5 Gy and 10 × 3 Gy for metastatic spinal cord compression using data from three prospective trials - Radiation Oncology

Background In a palliative situation like metastatic spinal cord compression (MSCC), overall treatment time of radiotherapy should be as short as possible. This study compared 5 × 5 Gy in 1 week to 10 × 3 Gy in 2 weeks in a prospective cohort. Methods Forty patients receiving 5 × 5 Gy in a phase...

ro-journal.biomedcentral.com

I remember some recent posts on here where people said they were using 5x5 for palliative spine, or at least for cord compression. Is this becoming a common practice, and do you just use 5 fx sbrt constraints?

In the paper Ray D Ayshun quotes, the do some mini-delving into radiobiology and alpha/beta etc. Thus my reason for bringing it up above. Speaking of Dirk Rades, he cites himself in the OP's paper in this study...

Purpose: To compare the results of short-course vs. long-course radiotherapy (RT) for metastatic spinal cord compression.

Methods and materials: A total of 231 patients who underwent RT between January 2006 and August 2007 were included in this two-arm prospective nonrandomized study. Patients received short-course (n = 114) or long-course (n = 117) RT. The primary endpoint was progression-free survival (PFS). The secondary endpoints were local control (LC), functional outcome, and overall survival (OS). An additional 10 potential prognostic factors were investigated for outcomes. PFS and LC were judged according to motor function, not pain control.

Results: The PFS rate at 12 months was 72% after long-course and 55% after short-course RT (p = 0.034). These results were confirmed in a multivariate analysis (relative risk, 1.33; 95% confidence interval, 1.01-1.79; p = 0.046). The 12-month LC rate was 77% and 61% after long-course and short-course RT, respectively (p = 0.032). These results were also confirmed in a multivariate analysis (relative risk, 1.49; 95% confidence interval, 1.03-2.24; p = 0.035). The corresponding 12-month OS rates were 32% and 25% (p = 0.37). Improvement in motor function was observed in 30% and 28% of patients undergoing long-course vs. short-course RT, respectively (p = 0.61). In addition to radiation schedule, PFS was associated with the interval to developing motor deficits before RT (relative risk, 1.99; 95% confidence interval, 1.10-3.55; p = 0.024). LC was associated only with the radiation schedule. Post-RT motor function was associated with performance status (p = 0.031), tumor type (p = 0.013), interval to developing motor deficits (p = 0.001), and bisphosphonate administration (p = 0.006). OS was associated with performance status (p < 0.001), number of involved vertebrae (p = 0.007), visceral metastases (p < 0.001), ambulatory status (p < 0.001), and bisphosphonate administration (p < 0.001).

Conclusion: Short-course and long-course RT resulted in similar functional outcome and OS. Long-course RT was significant for improved PFS and improved LC.

... which begins to make my point. When faced with a 25/5 or a 30/10 decision for spinal cord compression, I guess I'm choosing 30/10, or more, almost every time unless I see major problems with 2 weeks versus 1 week logistically (ie very low KPS!). I see the 25/5 had a non-sign trend toward better PFS but I don't know if deaths were censors or events. That's important to know in a metastatic spine RT study.

I have no data that 25/5 is superior to 30/10 (or anything "more"). Or, at the very least, the picture is murky that 25/5 would be in any ways better than 30/10. Oh. And also, there's this...

S.C.C. 25/5 = ((e^(-5/3))^5)*1E9 = ~240,000 cells remain

S.C.C. 30/10 = ((e^(-3/3))^10)*1E9 = ~45,000 cells remain

 

[metallica81788]

I would love to be able to have VMAT plans like that for palliative spines...

 

[TheWallnerus]

I would love to be able to have VMAT plans like that for palliative spines...

We can when Medicare. Palex's is a pretty special case I wager the private insurances would approve too.

 

[medgator]

I would love to be able to have VMAT plans like that for palliative spines...

Cigna approves a baseball bat, generally