For those of you who see a lot of high risk prostate cancer. Say you are treating prostate 60Gy/20 and bilateral nodal regions to 44Gy/20 via SIB. Which of the subvolmes includes SV? Thanks
Only case like this I ever had. Once saw a guy who had RP by the chair of urology Miami few years prior. Had a rising PSA. Did an MRI. Very suspicious finding in SVs. I was surprised… don’t you always remove SVs w/ an RP?? Evidently not. Read the op report… no mention of SVs coming out. (No super high risk features on path.) I consulted my local urologist and had him do directed biopsy of the SVs … in the juicy part. Lo and behold was positive. IMRTd it with high dose and short course AAT.I just include 1 cm of seminal vesicles and don’t dose paint. Almost all sv invasion is within .3 cm of prostate.
I haven't seen anything that suggests hypofx has inferior outcomes. There is this small exclusively high risk trial (using 3DCRT) that showed superior outcomes with hypofx. Good PS patients get brachy in our group but the others mostly get hypofx. Nothing wrong with standard fx either but for me it's kinda like when breast was starting to get hypofractionated and we would hold out on triple neg, large separation, prior chemo etc but now they all by and large get hypofx. I'd just be shocked if there were worse oncologic outcomes in any sort of (non FLAME style) conv vs hypo study.Since I know this question is a hill which many Radiation Oncologists will eagerly climb to spill their blood while defending their opinion, let me preface this by saying: I don't think there is a "right" answer, I just genuinely want to hear thoughts. This question of SV painting is a good jumping off point, because I've had this conversation recently and I find it interesting.
My Google search history is littered with the phrase: "high risk prostate cancer hypofrac data". I probably search at least once a week, looking for...I don't know. The Answer, I guess.
For those of you who are treating high risk or very-high risk prostate cancer, including nodes, with 70/28 or 60/20: why?
I don't feel like Googling again but weren't only ~120 CHHiP patients high risk? I think the data is bountiful for low and intermediate risk, obviously. But if you put a gun to my head and demanded I justify hypofrac for high risk with covering nodes, I don't know if I can weave together a compelling argument knowing that many of these trials either didn't have high risk patients or only had a few of them.
But, I've watched some of you author compelling treatment justifications in a single paragraph so...can someone help me give Google and PubMed a break for at least a month? The internet is tired of me asking.
I'm not super familiar with that paper, I need to dig into it. My immediate reaction from the abstract is 1) it's 3D, 2) it's from 2003-2007 which might have other implications about technology/support/workflows etc, 3) it used 9 months of ADT, 4) it has only 3 years of follow-up. I'm curious if they have longer follow-up publications now.I haven't seen anything that suggests hypofx has inferior outcomes. There is this small exclusively high risk trial (using 3DCRT) that showed superior outcomes with hypofx. Good PS patients get brachy in our group but the others mostly get hypofx. Nothing wrong with standard fx either but for me it's kinda like when breast was starting to get hypofractionated and we would hold out on triple neg, large separation, prior chemo etc but now they all by and large get hypofx. I'd just be shocked if there were worse oncologic outcomes in any sort of (non FLAME style) conv vs hypo study.
This is one of this "urban myths" of radiation oncology. It's quite possible that high gleason score is associated with a higher a/b, however in subgroup analyses of the randomized trials testing hypofractionation vs. normofractionation, no signs of worse outcomes with hypofractionation in high gleason scores were shown.Also, I'm aware that I should follow my comment up with checking out the basic science literature for alpha/beta values in high Gleason grades, if such a paper exists, but it's been a long day and I just can't muster the energy.
Are you TRYING to summon the ghosts of Radiation Biologists with that statement? It's Christmas, not Halloween. Check your calendar!This is one of this "urban myths" of radiation oncology. It's quite possible that high gleason score is associated with a higher a/b, however in subgroup analyses of the randomized trials testing hypofractionation vs. normofractionation, no signs of worse outcomes with hypofractionation in high gleason scores were shown.
The same also applies for breast cancer. We never saw that G3 tumors, for instance, fare worse with hypofractionation than with normofractionation and the hypofractionation trials on breast cancer also assumed a low a/b for breast cancer cells.
What potentially can be explanation for this,:
1. Any effect on less favorable local control with hypofractionation in aggresive forms of prostate and breast cancer does not pop up in PFS/OS-graphs, because these patients are also at high risk of systemic progression, irrelevant of local control. Thus, whether or not you eradicate all cancer cells in the prostate or lumpectomy cavity is irrelevant, since these patients are already micrometastatic.
2. Systemic treatment, which is generally intensified in these patients (long term ADT / chemotherapy), manages to close the gap in less favorable local control.
I choose a middle way out of this dillema.However, it occurred to me that if they WERE high risk, I don't know if I could give them a convincing argument about "hypofrac for high risk prostate", given 1) the incongruence in the radiation biology justifications and 2) the lack of inclusion of these patients in the non-inferiority trials.
The same also applies for breast cancer. We never saw that G3 tumors, for instance, fare worse with hypofractionation than with normofractionation
This is one of this "urban myths" of radiation oncology. It's quite possible that high gleason score is associated with a higher a/b
The data is not 100% pure in supporting your two propositions for breast and prostate respectively. It's mostly pure but not totally pure. I could put forward some arguments... which could easily be counter-argued. IMHO, I think it's very possible higher Gleason has higher a/b. Look at the a/b 95% C.I.'s in papers that try to solve the a/b prostate problem. TBH I think looking at things like G3 and Ki67 in regards to a/b in breast cancer is under-studied. Gleason's and grading are crude tools but likely rough surrogates for "biomolecularaties" which almost certainly heterogenize a/b in individual disease sites.I treat patients with high-risk disease without major comorbidities with electiv pelvic RT with conventional fractionation,
This is how I am currently choosing to practice as well (for high and very high risk).I hypofract pts who live far away. Conventional for rest.
The data is not 100% pure in supporting your two propositions for breast and prostate respectively. It's mostly pure but not totally pure. I could put forward some arguments... which could easily be counter-argued. IMHO, I think it's very possible higher Gleason has higher a/b. Look at the a/b 95% C.I.'s in papers that try to solve the a/b prostate problem. TBH I think looking at things like G3 and Ki67 in regards to a/b in breast cancer is under-studied. Gleason's and grading are crude tools but likely rough surrogates for "biomolecularaties" which almost certainly heterogenize a/b in individual disease sites.
AND then at the end you conventionally fractionate the nodes. Ha. We know the lion by his claw.
Why not go all the way? Instead of 4-5 weeks howsabout 4-5 treatments?Since I know this question is a hill which many Radiation Oncologists will eagerly climb to spill their blood while defending their opinion, let me preface this by saying: I don't think there is a "right" answer, I just genuinely want to hear thoughts. This question of SV painting is a good jumping off point, because I've had this conversation recently and I find it interesting.
My Google search history is littered with the phrase: "high risk prostate cancer hypofrac data". I probably search at least once a week, looking for...I don't know. The Answer, I guess.
For those of you who are treating high risk or very-high risk prostate cancer, including nodes, with 70/28 or 60/20: why?
I don't feel like Googling again but weren't only ~120 CHHiP patients high risk? I think the data is bountiful for low and intermediate risk, obviously. But if you put a gun to my head and demanded I justify hypofrac for high risk with covering nodes, I don't know if I can weave together a compelling argument knowing that many of these trials either didn't have high risk patients or only had a few of them.
But, I've watched some of you author compelling treatment justifications in a single paragraph so...can someone help me give Google and PubMed a break for at least a month? The internet is tired of me ask
Uggh I know, I know.
I am sure almost all prostate pts can be treated w/just 4-5 fractions, but then we would loose staff and resources.
You know...for all the saber rattling in the literature and on Twitter, sure seems like a lot of folks are still using conventional (I see it a lot on my geographic area, too).Fortunately, nearby pps exempt center not big on hypof (despite seminal publications), so not under much competitive pressure yet.
For those of you who are treating high risk or very-high risk prostate cancer, including nodes, with 70/28 or 60/20: why?
Can we bill that 3 fractions as an SBRT boost stateside ?I choose a middle way out of this dillema.
I treat patients with high-risk disease without major comorbidities with electiv pelvic RT with conventional fractionation, the boost the prostate with hypofractionation.
For instance pelvis + prostate 50.4/1.8 followed by prostate 24/3. That comforts me.
Excellent point!Some of the best evidence for treating nodes in high-risk prostate cancer comes from POP-RT. Patients in POP-RT were treated with hypofractionation (conventional dose to nodes). While not a fractionation comparison, if treating nodes, one could argue this is the best evidence for doing so
(Nothing against conventional fractionation... except maybe the alpha/beta argument).
Thou shalt not SBRT boost.Can we bill that 3 fractions as an SBRT boost stateside ?
I see 70/28x as conventional fractionation. Just like Canadian breast regimen
I think he means 24Gy in 8Fx of 3Gy a piece. Took me a while to learn how Palex writes his scripts.Can we bill that 3 fractions as an SBRT boost stateside ?
Oh! I thought 24 / 3No. Increased risk of acute GI toxicity separates it from THE standard for me.
I think he means 24Gy in 8Fx of 3Gy a piece. Took me a while to learn how Palex writes his scripts.
No harm in doing hypofx when doing nodes, but minimal comparison data.
You are all confusing me!Oh! I thought 24 / 3
sneaky palex
8/1 has less acute toxicity than 30/10, but which one is standard again??
Yet it couldn't make the cut for "choosing wisely" .... Guess that retreatment rate difference mattered to someoneOh! I thought 24 / 3
sneaky palex
8/1 has less acute toxicity than 30/10, but which one is standard again??
No, the publications refers to the M0 cohort of STAMPEDE. There are two main cohorts in STAMPEDE:I have to go down the complicated VPN tunnel to get the full paper and haven't done so yet, but I assume all of these patients got 55/20? Or did this subset of patients get a different regimen?
Don't reward my laziness! But I appreciate you digging this out.No, the publications refers to the M0 cohort of STAMPEDE. There are two main cohorts in STAMPEDE:
- locally advanced N0/N1
- metastastic M1
These patients are the first cohort and received standard, normofractionated radiotherapy of the prostate +/- pelvis
2018-version of the protocol is available here.
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Do you do 7 Gy x 10 for LN+ H&N cancer? If a/b is just a scam, all that should matter is total dose 😜
10 x 7 Gy for HNSCC sounds like an excellent regime. It will lead to very high local control rates.Do you do 7 Gy x 10 for LN+ H&N cancer? If a/b is just a scam, all that should matter is total dose 😜
With a high enough dose of RT, you can kill just about anything10 x 7 Gy for HNSCC sounds like an excellent regime. It will lead to very high local control rates.
Except for tardigrades apparently.With a high enough dose of RT, you can kill just about anything
Except for tardigrades apparently.
They actually can quite literally walk through that valley…
You sure do know a lot about tardigrades...They actually can quite literally walk through that valley…
This Is How Tardigrades Walk, And We Were Not Ready For The Footage
Tardigrades are undoubtedly weird.www.sciencealert.com
“How do you know so much about tardigrades?”You sure do know a lot about tardigrades...
You sure do know a lot about tardigrades...