liver SBRT for single large lesion

[Kroll2013]

Dear colleagues,

your opinion is highly appreciated:


55 years old female, diagnosed of a pancreatic adenocarcinoma in 2017. She underwent a Whipple surgery followed by adjuvant chemoradiation to the tumor bed using a 3 fields 3D-conformal plan.
In 2019, she developed a single liver lesion of 2.5 cm , segment VIII treated with RFA.
3 months after, the lesion progressed in size reaching 7 cm , CA19-9 5000, with no other secondary lesion elsewhere.
Her liver function is maintained, only GGT and ALP are elevated.
Screenshots of her MRI and delineated CT sim are attached below.

GTV acc volume: 291 cc
PTV volume: 436 cc
Liver-GTVacc volume: 1000 cc

Is Iiver SBRT an option?
What dose and fractionation do you recommend?

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[Pointless]

Ugh. Tough case. You can plan it out to see if you can meet the 700 cc <15 Gy liver constraint, but I'd say probably not. If this is the only site of disease and you feel compelled to treat definitively(ish), maybe 60 in 15?

 

[Neuronix]

Options:

1. This is a great case for proton radiotherapy, especially with breathhold. You'd spare the rest of the liver.

2. Failing that, I'd get the PTV as small as possible with MRI-guidance and run a plan. Without MRI-RT, do fiducials with good breathhold technique on linac. I'd see what dose I could put in per RTOG 1112 while meeting liver constraints.

3. Would consider Y-90. I haven't done any cases in years, but I'd see what IR thinks about flow to that. You might be able to get a high dose in and be pretty selective in a case like this.

 

[ramsesthenice]

Dear colleagues,

your opinion is highly appreciated:


55 years old female, diagnosed of a pancreatic adenocarcinoma in 2017. She underwent a Whipple surgery followed by adjuvant chemoradiation to the tumor bed using a 3 fields 3D-conformal plan.
In 2019, she developed a single liver lesion of 2.5 cm , segment VIII treated with RFA.
3 months after, the lesion progressed in size reaching 7 cm , CA19-9 5000, with no other secondary lesion elsewhere.
Her liver function is maintained, only GGT and ALP are elevated.
Screenshots of her MRI and delineated CT sim are attached below.

GTV acc volume: 291 cc
PTV volume: 436 cc
Liver-GTVacc volume: 1000 cc

Is Iiver SBRT an option?
What dose and fractionation do you recommend?
View attachment 294602
View attachment 294603
View attachment 294604

Your liver-GTVacc volume doesn't look quite right. The patient appears to have a good size liver and the numbers don't seem to add up quite right. I would have expected liver + GTV to be closer to 2000 ccs or so.

Be it as it may, depending on the kind of gating that you have I would be you could treat this thing with SBRT (45-50 Gy in 3-5 fractions) and meet reasonable constraints. Should you? I don't know. I have yet to find one of these cases that ends up being gratifying. Its so tempting when there is "only 1" lesion but it seems like without fail we treat the one we see, make it mad, and it decides to make more friends. If it is symptomatic I would probably give it a healthy palliative dose (40 Gy in 5 fractions or something thereabouts) and call it a day. The upside to going higher is pretty limited in these situations. Hate to sound like a nihilist, but this one feels like it is really pushing the boundary of what is reasonable.

 

[Lamount]

At the risk of earning the hatred of every person here, would be a great case for protons.

with photons, I would stick with 60/15 fractions and pump as much dose as you can in with SIB while meeting Crane constraints.

 

[Cowy1]

Y90 is probably the best answer (in a sea of marginal) here.

 

[Palex80]

10 x 5 Gy @60% isodose. Try it.

 

[Haybrant]

At the risk of earning the hatred of every person here, would be a great case for protons.

with photons, I would stick with 60/15 fractions and pump as much dose as you can in with SIB while meeting Crane constraints.

Agree case for proton

 

[seper]

My gut feeling is to do 35 Gy/10.

 

[probiotic]

Image-guided Liver BrachyAblation

Comparative analysis between interstitial brachytherapy and stereotactic body irradiation for local ablation in liver malignancies - PubMed

To the best of our knowledge, this is the first report on the comparison of clinically treated liver BT treatments with virtually planned SBRT treatments. The planning study showed a superior outcome of BT regarding dose coverage of the target volume and exposed liver volume. Nevertheless...

www.ncbi.nlm.nih.gov

 

[seper]

taking brachytherapy heroism to a new level

 

[Reaganite]

Is this disease that has grown through salvage chemotherapy?

 

[Aphtalyfe]

I'd try 50Gy in 5 and if constraints can't be met, then I would drop the dose to 45 in 5 and then again to 40 in 5 if still unable to meet. I would attempt to keep the center(ish) to 50Gy in 5 though using SIB.

Image-guided Liver BrachyAblation

Comparative analysis between interstitial brachytherapy and stereotactic body irradiation for local ablation in liver malignancies - PubMed

To the best of our knowledge, this is the first report on the comparison of clinically treated liver BT treatments with virtually planned SBRT treatments. The planning study showed a superior outcome of BT regarding dose coverage of the target volume and exposed liver volume. Nevertheless...

www.ncbi.nlm.nih.gov

We've done liver brachy... but that lesion is a bit big. In the study above their highest volume was 410cc.

 

[RickyScott]

btw I have found compression belt helps for lesions like this. Would also go for 50/5 and if cant meet 67.5/15 Chris Crane

 

[mheat3]

btw I have found compression belt helps for lesions like this. Would also go for 50/5 and if cant meet 67.5/15 Chris Crane

Agree, 67.5/15 is a nice regimen for these larger lesions when 5 fraction liver constraints are tough to meet.

 

[deleted950463]

from an IR prospective Y90 really is only used for things that are at least decently hypervascular. One can consider radiation segmentecomy but even then I am concerned that our brachytherapy y90 particles just aint gonna penetrate this whole thing.

if this is in my institution, I would be happy to place as many ficiduals as you need for you to zap this thing.

this is also a bit too big for ablation.

this is one thing that I will bounce to radonc first line if I see in tumor board. Y90 mapping if everyone extremely onboard. Will not treat if mapping shows any hetergenity in the uptake in that thing. Y90 just really isnt done for pancreatic CA mets.

 

[Palex80]

We've done liver brachy... but that lesion is a bit big. In the study above their highest volume was 410cc.

In my humble opinion, attempting brachytherapy at huge liver lesions will result in the same disasters some of us may have seen when interventional radiologists attempted to do a TACE for a big lesion (or RFA for a rather big lesion). You would end up with a huge necrotic area, which will turn into an abscess in the worst case scenario if you also induce a cholangitis (which is possible according to location of lesion). That's a very bad end result with potential lethal outcome for the patient. Needless to say, you would either have to insert multiple catheters for such a big lesion or your dose distribution will also look horrible in a brachy plan, leading to a dose of hundreds of Grays in the middle of the lesion (and I am not talking about point dose, but dose to may cm3) in order to get some kind of ablative dose at the periphery of the lesion.

 

[Gfunk6]

10 x 5 Gy @60% isodose. Try it.

Agree. In these scenarios we stick in a few fiducials and use tracking for treatment.

 

[evilbooyaa]

Lots of interesting answers here:

I assume patient has been on chemo and has failed at least 1 if not 2 lines of systemic therapy, given that this is a pancreatic met. I would focus on palliation as patient most likely to die due to distant metastatic disease.

First thing - 3D for pancreatic adeno was done in 2017.... how? AP/PA? 4-Field? If 4-field then a lot of the liver has seen dose already. Make sure you're doing composite plans. What does 3-field mean? A lateral beam? Entering through the liver side or spleen side? I guess my concern is just what dose has the liver gotten already. Don't send this poor patient into liver failure with whatever you do.

I would do 5 fraction, shoot for 700cc of liver getting < 15Gy, but would relax to 21 as necessary. I would double check your liver, as I think liver - GTV of 1000cc seems small given what you've shown on the CT slices. Would turn down dose to 40/5 as necessary (although goal of 50/5) to meet constraints.

If truly not feasible even at 40/5 then would fractionate more.

Prescribe to low isodose line and allow more dose to spill into Chest Wall than lung as feasible.

Fiducials and end expiratory breath hold as tolerated, otherwise 4DCT with portal venous phase constrast and abdominal compression.

This would be a very reasonable case for IMPT but certainly not mandatory unless you can't meet using other techniques.

That being said, it's palliation and I don't know how many people would be willing to use protons for palliation.

 

[Aphtalyfe]

In my humble opinion, attempting brachytherapy at huge liver lesions will result in the same disasters some of us may have seen when interventional radiologists attempted to do a TACE for a big lesion (or RFA for a rather big lesion). You would end up with a huge necrotic area, which will turn into an abscess in the worst case scenario if you also induce a cholangitis (which is possible according to location of lesion). That's a very bad end result with potential lethal outcome for the patient. Needless to say, you would either have to insert multiple catheters for such a big lesion or your dose distribution will also look horrible in a brachy plan, leading to a dose of hundreds of Grays in the middle of the lesion (and I am not talking about point dose, but dose to may cm3) in order to get some kind of ablative dose at the periphery of the lesion.

I mean... I said it's a bit big.

 

[Lamount]

Out of curiosity, what is the argument for 5 fractions here? Your rx dose is severely limited by constraints. Why not get in as much dose as you can with ~15 fx?

 

[radoncgrad2019]

have you considered 60 Gy/60 fx? Scarbtj used to do that back in day pre- you know what

 

[radiation]

Michigan has a nice approach when you give 3 fractions and then give a month long break and replan for last 2 fractions if needed for HCC

https://www.thegreenjournal.com/article/S0167-8140(19)33020-8/fulltext

Bob Timmerman has also recently pitched a new concept called PULSAR where you give monthly adaptive fractions. No data that I find yet, however.


If the fractions are spread apart far enough, could one charge each fraction as a new course of treatment ? Is this the countermove to hypofractionation?

 

[ramsesthenice]

Out of curiosity, what is the argument for 5 fractions here? Your rx dose is severely limited by constraints. Why not get in as much dose as you can with ~15 fx?

It depends on how much it moves and what kind of gating they use but there is a good chance since it’s peripheral they can meet constraints. Dose isn’t the issue. Histology is the problem. There is almost no data supporting liver-directed therapy for metastatic pancreatic adenocarcinoma. Especially one that is not behaving great. Sounds like this thing ballooned shortly after attempted ablation.