High risk prostate fractionation

[radoncle]

How are you fractionating prostate treatments when treating pelvic nodes? Conventional? Hypofrac?

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[Gfunk6]

Generally still using conventional 1.8 Gy/2.0 Gy to 45 Gy/50 Gy. But when time is a factor I will do 40 Gy in 16 fx

 

[BobbyHeenan]

I do a fair amount of 70 Gy in 28 to prostate, 50.4 to nodes. However I limit small bowel to 50.4 Gy max point and under cover elective PTV's to limit bowel toxicity... so my elective dose on nodes can be "cold" but I don't think it's worth it to push elective doses in this situation.

I still do some standard frac too in this situation at 2 Gy/fraction 48-50 Gy then boost prostate to 78-80.

I haven't done any 5 fraction or 20 fraction nodal treatments (yet).

 

[elementaryschooleconomics]

I also generally use conventional (45 in 25 to nodes).

 

[medgator]

Conventional fx or 70/28 (50.4 to nodes) are both reasonable options

 

[Ray D. Ayshun]

How are you fractionating prostate treatments when treating pelvic nodes? Conventional? Hypofrac?

Conventional to nodes while sibing prostate with hypofx.

 

[Palex80]

We generally do WPRT with 1.8-2.0 Gy up to 45-50.4 Gy.
We generally deliver the sequential boost to the prostate in a hypofractionated manner with 2.5-3.0 Gy (for instance with 8 x 3 Gy).

 

[RickyScott]

I fractionate conventionally all the way.

 

[grenz]

We generally do WPRT with 1.8-2.0 Gy up to 45-50.4 Gy.
We generally deliver the sequential boost to the prostate in a hypofractionated manner with 2.5-3.0 Gy (for instance with 8 x 3 Gy).

Is there data for this approach?

 

[jondunn]

I fractionate conventionally all the way.

1.8s or bust

 

[Palex80]

Is there data for this approach?

None, that I am aware of. But I do not see why this should not be safe.

It's "green" radiation oncology a.k.a. "hypofractionation"

 

[Pointless]

I use 70/28 with 47.6/28 nodes. Concocted it myself using EQD2 but have seen it elsewhere. Works nicely.

 

[grenz]

I use 70/28 with 47.6/28 nodes. Concocted it myself using EQD2 but have seen it elsewhere. Works nicely.

I like this. It always gives me pause to escalate the pelvic dose just so we can finish faster with hypofrac. I’m humbled by the fact that almost every long term survivor that I’ve met who had RT many years ago has some sort of late toxicity

 

[Ray D. Ayshun]

Correction re my other post as I don't dose escalate the pelvis. If i treat the pelvis in node negative I do 45/25 while treating the prostate to 62.5/in 25 followed by a 7.5/3 boost. If node positive I treat gross disease to 70/28 and pelvis to 50/4/28.

 

[jondunn]

I use 70/28 with 47.6/28 nodes. Concocted it myself using EQD2 but have seen it elsewhere. Works nicely.

I do 70 and 50.4 but I’m gonna switch to lower for pelvic now, makes sense

 

[HolySmokes]

I do 70 and 50.4, just allow significant underdosing as long as PTV is getting 47.6

 

[DoctwoB]

Y’all forgot the brachytherapy

 

[Ray D. Ayshun]

Y’all forgot the brachytherapy

my isodose lines are so tight i've been calling the sib "virtual brachytherapy."

 

[metallica81788]

I use 70/28 with 47.6/28 nodes. Concocted it myself using EQD2 but have seen it elsewhere. Works nicely.

This is what I do.

When I first started my plan was to standard frac all high risk patients but I was fraction shamed at my chart rounds so converted to 70/28 w 47.6 nodes and have done that for most of my high risks (chose not to fight this battle). Most of my high risks are older and difficult logistics so I would be doing this for a fair amount regardless of the virtue signaling.
However now I have a low threshold in high risk for doing standard given my annoyance with the acute GU toxicities of hypofrac

 

[deleted1116990]

Dose matters.

I prefer to treat high risk with a 2 fraction SBRT boost (20 Gy) followed by 46 Gy in 23 fractions to the pelvis.

Otherwise I will prefer to treat with conventional fractionation and give a slight SIB in the 85-90 range to the gross disease on MRI/PSMA pet.

Fiducials, spaceOAR, daily CBCT.

 

[Gfunk6]

Dose matters.

I prefer to treat high risk with a 2 fraction SBRT boost (20 Gy) followed by 46 Gy in 23 fractions to the pelvis.

Otherwise I will prefer to treat with conventional fractionation and give a slight SIB in the 85-90 range to the gross disease on MRI/PSMA pet.

Fiducials, spaceOAR, daily CBCT.

I approach identically in high-risk cases. However, I try to emulate HDR dosing on the boost 9.5 Gy x 2 with a very heterogenous dose (50-70% IDL).

 

[communitydoc13]

Dose matters.

I take the opposite approach. SIB 4500/6250 with 750 Boost to prostate or prostate/SV.

Dose matters for biochemical control, but I've yet to see it matter beyond this type of dosing for survival. My interpretation of ASCENDE-RT among others is that really bad disease escapes local treatment and becomes life threatening independent of dose but recapitulation of lower risk disease years later is preferentially treated by higher dose. (Low grade late recurrences happen after surgery many years down the road as well).

If patient is young (young sixties on down), healthy and not getting surgery, I will refer for brachy boost after 4500. But the vast majority of my 70+ high risk patients are treated as above.

I have no hesitation to push for incorporation of Zytiga up front in Gleason 9 and 10 disease.

 

[jondunn]

This is the way they think

 

[deleted1116990]

I take the opposite approach. SIB 4500/6250 with 750 Boost to prostate or prostate/SV.

Boost matters for biochemical control, but I've yet to see it matter beyond this type of dosing for survival. My interpretation of ASCENDE-RT among others is that really bad disease escapes local treatment and becomes life threatening independent of dose but recapitulation of lower risk disease years later is preferentially treated by higher dose. (Low grade late recurrences happen after surgery many years down the road as well).

If patient is young (young sixties on down), healthy and not getting surgery, I will refer for brachy boost after 4500. But the vast majority of my 70+ high risk patients are treated as above.

I have no hesitation to push for incorporation of Zytiga up front in Gleason 9 and 10 disease.

I would argue that 45 in 25 is not adequate nodal dose for prostate.
If I understand you correctly, you are saying that local control via dose escalation is less important in high risk disease due to distant failure. I still think it makes sense to be locally aggressive.
Perhaps the issue is that 46/23 or 50.4/28 is not adequate nodal dose either (it probably isn't), which raises the question why are even treating the nodes at all? I am not an anti-noder. While I almost always treat nodes in high risk patients, with the results of POP-RT, perhaps we are just kicking the can down the road and alternatively can salvage isolated nodal failures with SBRT or a conventionally fractionated field above the prior field if needed to further kick the can down the road (I have a man I am doing this now on who refuses ADT and having him void before treatment to keep bladder entirely out of the field). This is basically the same logic as not escalating the prostate. If you are not going to escalate treatment in the prostate due to no OS difference and patients metting out eventually, then why escalate treatment with nodes to increase regional control temporarily but presumably eventually also fail distantly (will need long term data from POP-RT but if this hypothesis is true would eventually expect to see no difference in DMFS). For some older high risk patients, who *should* be getting surveillance in low-intermediate risk disease due to limited life expectancy from age or other medical conditions, I will just SBRT the prostate and leave the nodes alone. 11% high risk patients with 7-fraction "SBRT".

Regardless, I am not sure about being less aggressive locally in high risk disease. I prefer the opposite, but honestly I roll my eyes when people get dogmatic about treatment in high risk disease. It's not that clear. I should probably clarify when I said "dose matters" that "I think dose seems to matter."

 

[deleted1111261]

We give much higher BED to stage I lung than stage III lung.

 

[medgator]

We give much higher BED to stage I lung than stage III lung.

Chemo/IO? Synergistic therapies requiring less RT dose

 

[salubalu]

I've been doing 37.5-40 to the prostate and 25 in 5 to nodes on trial.

 

[RSAOaky]

On the rare occasions I see these patients (thanks Urorads) I do 44 fractions and I justify it by saying the hypofrac trials didn't treat nodes. I feel guilty about it every time (SHAAAAAAAAME) but daddy's gotta eat. If they need to be done quicker or they see my non-RVU driven academic counterparts first and are told they can be done in 6 weeks, I do 70/50.4 in 28 and have no problem with it. I did 79.2/50.4 in residency all the time.

 

[seper]

For those who treat nodes routinely, how do you justify that? High quality diagnostic imaging picks up positive nodes pretty reliably.

I see the opposite trend in high-risk prostate Ca : people would just do Cyberknife in 5 fractions + hormones (often for less than 2 years)

 

[Palex80]

For those who treat nodes routinely, how do you justify that? High quality diagnostic imaging picks up positive nodes pretty reliably.

Do you mean how do I justify treating nodes electively? POP-RT is the answer to that.

 

[Pointless]

On the rare occasions I see these patients (thanks Urorads) I do 44 fractions and I justify it by saying the hypofrac trials didn't treat nodes. I feel guilty about it every time (SHAAAAAAAAME) but daddy's gotta eat. If they need to be done quicker or they see my non-RVU driven academic counterparts first and are told they can be done in 6 weeks, I do 70/50.4 in 28 and have no problem with it. I did 79.2/50.4 in residency all the time.

I mean.... just admitting that you over-fractionate for $$? Come on man....

 

[jondunn]

I mean.... just admitting that you over-fractionate for $$? Come on man....

Like my thing is if you’re going to do long fractionation schemes at least have the thieves honor of doing 2 gy/fx and not 1.8s

 

[salubalu]

I’m excited about incorporation of decipher/genomics and seeing how we can escalate or de escalate therapy using it.

 

[RSAOaky]

I mean.... just admitting that you over-fractionate for $$? Come on man....

Yea I know, it feels dirty. It's probably 3 patients a year though so I sleep alright. Every other prostate or breast gets hypofraced.

And just to be clear, anyone who doesn't admit they over-fractionate for the money just does a better job of lying to themselves than I do, including the entire generation of radoncs that came before me. When Start B and Whelan were published and adopted my attendings continued to do 50 in 25 because "we don't have long term outcome data." Or they'd treat DCIS to 50 in 25 because DCIS wasn't included on the hypofrac trials.

Even you guys doing 70 in 28, why not do 60 in 20? I bet you treat all your rectums in 5 fractions, all your early stage breasts in 5 fractions, hypofrac all your regional nodal breast patients ("oh I would but we don't have the toxicity data"), treat all bone mets to 8 Gy in 1, don't radiate pancreas because there's no OS benefit, do 3 fraction cuff brachy, etc etc etc.

It's easy to get up on the soapbox and shame the individual, but if every radonc in America actually followed our fractionation data we would have instant job market collapse.

 

[deleted1111261]

If someone states they do it for a few extra $$$, that is far more logical then the nonsense of DCIS not being included or finding every reason not to do RAPIDO. At least I understand and it makes sense, rather than cognitive dissonance.

Have to do it keep RTTs employed 40 hours? Fine. Not your fault admin looking at on beam numbers. Have to do it to meet your RVU threshold? Not your fault system is using widget production model.

 

[Ray D. Ayshun]

If someone states they do it for a few extra $$$, that is far more logical then the nonsense of DCIS not being included or finding every reason not to do RAPIDO. At least I understand and it makes sense, rather than cognitive dissonance.

Have to do it keep RTTs employed 40 hours? Fine. Not your fault admin looking at on beam numbers. Have to do it to meet your RVU threshold? Not your fault system is using widget production model.

I disagree about rapido. Not sure why it's so hard to do a tnt trial with sc > chemo > surgery vs lc/chemo or chemo/lc > surgery. There's were the makings of better local control in the long course arm. It doesn't feel like a dumb justification to me. To me, the trial supports neoadjuvant chemo, but continues to leave rt choice as a point of contention. But daddy's got to eat...

 

[RSAOaky]

If someone states they do it for a few extra $$$, that is far more logical then the nonsense of DCIS not being included or finding every reason not to do RAPIDO. At least I understand and it makes sense, rather than cognitive dissonance.

Have to do it keep RTTs employed 40 hours? Fine. Not your fault admin looking at on beam numbers. Have to do it to meet your RVU threshold? Not your fault system is using widget production model.

Exactly. If my employer said "you know what RSAOaky, we're going to freeze your pay at the current level indefinitely but we really want you to minimize your fraction usage. We promise not to fire any of your staff and to pay everyone a full time salary for 20 hours of work a week in perpetuity" I'm sure we'd all be ecstatic.

 

[deleted1111261]

I disagree about rapido. Not sure why it's so hard to do a tnt trial with sc > chemo > surgery vs lc/chemo or chemo/lc > surgery. There's were the makings of better local control in the long course arm. It doesn't feel like a dumb justification to me. To me, the trial supports neoadjuvant chemo, but continues to leave rt choice as a point of contention. But daddy's got to eat...

Oh, it’s fine to not use it and I’m sure the study will come out.

But reasons I’ve heard in tumor board

- “This patient has advanced nodal disease, so want to do long course” (RAPIDO patients were far more advanced)
- “The surgery is more toxic” (data does not support this”
- “Better pCR with long course” (not suggested by comparison of prodige vs rapido intervention arms)

 

[TheWallnerus]

Yea I know, it feels dirty. It's probably 3 patients a year though so I sleep alright. Every other prostate or breast gets hypofraced.

And just to be clear, anyone who doesn't admit they over-fractionate for the money just does a better job of lying to themselves than I do, including the entire generation of radoncs that came before me. When Start B and Whelan were published and adopted my attendings continued to do 50 in 25 because "we don't have long term outcome data." Or they'd treat DCIS to 50 in 25 because DCIS wasn't included on the hypofrac trials.

Even you guys doing 70 in 28, why not do 60 in 20? I bet you treat all your rectums in 5 fractions, all your early stage breasts in 5 fractions, hypofrac all your regional nodal breast patients ("oh I would but we don't have the toxicity data"), treat all bone mets to 8 Gy in 1, don't radiate pancreas because there's no OS benefit, do 3 fraction cuff brachy, etc etc etc.

It's easy to get up on the soapbox and shame the individual, but if every radonc in America actually followed our fractionation data we would have instant job market collapse.

INSTANT

 

[salubalu]

Oh, it’s fine to not use it and I’m sure the study will come out.

But reasons I’ve heard in tumor board

- “This patient has advanced nodal disease, so want to do long course” (RAPIDO patients were far more advanced)
- “The surgery is more toxic” (data does not support this”
- “Better pCR with long course” (not suggested by comparison of prodige vs rapido intervention arms)

better responses than I do not believe in it...like at tumor board when Protect trial came out and the Urologist said I do not believe it and walked out...

 

[masrawy]

My practice is for NCCN High Risk patients is 79.2Gy/44fx to the prostate/SV and 45Gy versus 50.4Gy to the pelvic nodes. Of note, not all academic groups do a hypofractionated regimen to the prostate/SV either, certainly we didn't during training. Our rationale was that, other than HYPRO, all of the trials directly comparing hypofrac to convention frac did not include patients with High Risk Prostate Cancer and the Phase III HYPRO trial, which did include High Risk patients, showed increased toxicity with the hypofrac regimen (Grade 3 or higher late GU toxicity was higher in the hypofractionated regimen)...

 

[JS1987]

SIB 60/20 44/20

 

[Chartreuse Wombat]

Like my thing is if you’re going to do long fractionation schemes at least have the thieves honor of doing 2 gy/fx and

My practice is for NCCN High Risk patients is 79.2Gy/44fx to the prostate/SV and 45Gy versus 50.4Gy to the pelvic nodes. Of note, not all academic groups do a hypofractionated regimen to the prostate/SV either, certainly we didn't during training. Our rationale was that, other than HYPRO, all of the trials directly comparing hypofrac to convention frac did not include patients with High Risk Prostate Cancer and the Phase III HYPRO trial, which did include High Risk patients, showed increased toxicity with the hypofrac regimen (Grade 3 or higher late GU toxicity was higher in the hypofractionated regimen)...

Not exactly true. CHHiP trial did include high risk patients (about 12%)

Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: 5-year outcomes of the randomised, non-inferiority, phase 3 CHHiP trial - PubMed

Cancer Research UK, Department of Health, and the National Institute for Health Research Cancer Research Network.

pubmed.ncbi.nlm.nih.gov

 

[Aphtalyfe]

Rarely conventionally fractionate prostate RT anymore...

45/25 to nodes/prostate + 15Gy x 1 brachytherapy boost
25/5 to nodes/prostate + SIB 40-45/5 to prostate
25/5 to nodes/prostate + 15Gy x 1 brachytherapy boost (on trial)

 

[masrawy]

Not exactly true. CHHiP trial did include high risk patients (about 12%)

Conventional versus hypofractionated high-dose intensity-modulated radiotherapy for prostate cancer: 5-year outcomes of the randomised, non-inferiority, phase 3 CHHiP trial - PubMed

Cancer Research UK, Department of Health, and the National Institute for Health Research Cancer Research Network.

pubmed.ncbi.nlm.nih.gov

Yes, you are right. I should have said "did not include good representation of high risk prostate cancer patients." We have dose escalated data showing improved biochemical free survival with dose escalation in a high risk population, yet as you pointed out, we have no good representation of high risk patients in trials comparing hypo versus conventional fractionation except for the HYPRO trial, and that represented good Phase III data suggesting it's more toxic in this cohort. I'm pro hypofractionation when all the data fits - I don't think it does here.

 

[JS1987]

Yes, you are right. I should have said "did not include good representation of high risk prostate cancer patients." We have dose escalated data showing improved biochemical free survival with dose escalation in a high risk population, yet as you pointed out, we have no good representation of high risk patients in trials comparing hypo versus conventional fractionation except for the HYPRO trial, and that represented good Phase III data suggesting it's more toxic in this cohort. I'm pro hypofractionation when all the data fits - I don't think it does here.

There is plenty of data. It is not one size fits all - like most of rad onc. Much phase II, single arm, and phase III randomized data. CHHiP data is high quality 12% very significant of >3000 pts. Hypro also shows safety and long term data favorable.

Large experience at Princess Margaret with 68/25 SIB: Elective pelvic nodal irradiation with a simultaneous hypofractionated integrated prostate boost for localized high risk prostate cancer: Long term results from a prospective clinical trial - PubMed

I am one physician, but I've been doing this for >5 years. Patients do fine with VMAT and daily CBCT. Hell, do SpaceOAR if you're concerned. I don't.

Btw, I still eat fine.

 

[masrawy]

There is plenty of data. It is not one size fits all - like most of rad onc. Much phase II, single arm, and phase III randomized data. CHHiP data is high quality 12% very significant of >3000 pts. Hypro also shows safety and long term data favorable.

Large experience at Princess Margaret with 68/25 SIB: Elective pelvic nodal irradiation with a simultaneous hypofractionated integrated prostate boost for localized high risk prostate cancer: Long term results from a prospective clinical trial - PubMed

I am one physician, but I've been doing this for >5 years. Patients do fine with VMAT and daily CBCT. Hell, do SpaceOAR if you're concerned. I don't.

Btw, I still eat fine.

Biology clearly matters significantly in prostate cancer as we see from the broad spectrum of treatment options we offer patients from active surveillance, local therapy, and aggressive local therapy combined with ADT and maybe also including nodes as well. So if biology matters, potentially less aggressive biology of 88% of patients on CHHiP may affect our interpretation when it comes to the 12% that were higher risk.

You're right that there is plenty of hypofractionation data with great experiences, but none randomized a majority of high risk patients to conventional versus hypo other than HYPRO. I appreciate that for some, that may be sufficient to treat without randomized data in a cohort representative of high risk biology, while for some it is not. Randomized data is important, because we commonly jump to assuming certain prostate cancer regimens are better, without looking at the factors that may explain some of it. Very different clinical situation and study, but look at POP-RT, they had excellent results and biochemical control rates in both arms (prostate only versus prostate plus nodes), but look at the fact that 80% of patients had PSMA-PET done as part of staging - clearly something like this affected eligibility on the trial (excluded lots of metastatic patients) and affects outcomes when we compare their results to other trials, but at least both arms on the study were fairly compared. It would not be fair to compare those arms directly to another study which did not have the same eligibility criteria.

Suffice to say, I think this is a controversy that exists in this field, and it is alright to disagree on the management. Importantly, however, not wanting to hypofractionate high risk patients is a reasonable philosophy one may have from an academic, non-business, perspective as well. Some may just want definitive randomized data comparing the two fractionation regimens and showing the same control without any increased toxicity in this cohort before making the switch.

 

[jondunn]

It’s not controversial in 2022

That being said all
Options in NCCN, so yeah

 

[Chartreuse Wombat]

Biology clearly matters significantly in prostate cancer as we see from the broad spectrum of treatment options we offer patients from active surveillance, local therapy, and aggressive local therapy combined with ADT and maybe also including nodes as well. So if biology matters, potentially less aggressive biology of 88% of patients on CHHiP may affect our interpretation when it comes to the 12% that were higher risk.

You're right that there is plenty of hypofractionation data with great experiences, but none randomized a majority of high risk patients to conventional versus hypo other than HYPRO. I appreciate that for some, that may be sufficient to treat without randomized data in a cohort representative of high risk biology, while for some it is not. Randomized data is important, because we commonly jump to assuming certain prostate cancer regimens are better, without looking at the factors that may explain some of it. Very different clinical situation and study, but look at POP-RT, they had excellent results and biochemical control rates in both arms (prostate only versus prostate plus nodes), but look at the fact that 80% of patients had PSMA-PET done as part of staging - clearly something like this affected eligibility on the trial (excluded lots of metastatic patients) and affects outcomes when we compare their results to other trials, but at least both arms on the study were fairly compared. It would not be fair to compare those arms directly to another study which did not have the same eligibility criteria.

Suffice to say, I think this is a controversy that exists in this field, and it is alright to disagree on the management. Importantly, however, not wanting to hypofractionate high risk patients is a reasonable philosophy one may have from an academic, non-business, perspective as well. Some may just want definitive randomized data comparing the two fractionation regimens and showing the same control without any increased toxicity in this cohort before making the switch.

"Some may just want definitive randomized data comparing the two fractionation regimens and showing the same control without any increased toxicity in this cohort before making the switch"

This data will never be forthcoming. If you haven't moved to hypo by now you never will (and that is OK)...unless capitation (ala RO APM) becomes the law of the land...then everyone moves to 5 fractions overnight

 

[RadRadRad]

I remember when the standard of care was typically set by randomized trials from North America. When most people switched to breast hypofrac there was 10 years of data from Whelan. For prostate with node coverage there is not anything like this kind of data for hypofrac

And for those in love with UK data, don’t forget about IORT. That data was almost assuredly fudged