Re-SRS in a patient who has had WBRT?

[Ray D. Ayshun]

All, wondering about precedence for this. I haven't treated this patient before, but to sum up, Extensive stage small cell initially with 2 brain mets. 30 Gy in 10 fx WBRT in March of 2019. Left cerebellar progression in May 2020 for which he got 18 Gy x 1. Since that time, he's been stable until recently when he had evidence of progression in the left cerebellum. Not rushing into anything, as I'm not entirely convinced this represents recurrent disease, but mostly curious if anyone has had a similar situation, and has re-srs'd something in someone who also had WBRT.

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[MidwestRadOnc]

It’s triple retreat small cell. Fractionate with tight margins if you must.

 

[Bequerel]

If convinced recurrence—6Gy x 5

 

[Neuronix]

If he's in shape for it and it's accessible, can consider resection vs ablation. This will tell you RT necrosis or active tumor (hopefully--given sampling error) and is a treatment for the area that can delay or avoid another course of RT.

I have done SRS+re-SRS to same target on top of WBRT many times. Necrosis risk is significant. Agree with 6 Gy x 5 based on educated guess.

 

[Ray D. Ayshun]

If he's in shape for it and it's accessible, can consider resection vs ablation. This will tell you RT necrosis or active tumor (hopefully--given sampling error) and is a treatment for the area that can delay another course of RT.

I have done SRS+SRS+WBRT many times. Necrosis risk is significant.

Had been wondering about RT necrosis in conjunction with someone who was on Eliquis, which could make for a new "mass." I know you see CNS. Does RT necrosis show up all at once 4 years later much (in patients who are still around)?

 

[BobbyHeenan]

If he's in shape for it and it's accessible, can consider resection vs ablation. This will tell you RT necrosis or active tumor (hopefully--given sampling error) and is a treatment for the area that can delay or avoid another course of RT.

I have done SRS+re-SRS to same target on top of WBRT many times. Necrosis risk is significant. Agree with 6 Gy x 5 based on educated guess.

Agree.

I also call up med onc and let them know that bevacizumab may be needed - some of them in my neck of the woods are unfamilair with its use in necrosis and there can be some delay in insurance auth, etc. So reminding them of that indication and start thinking about logistics. I agree with you, in my limited case series in this situation I'd say necrosis is at least 30-50%.

 

[Neuronix]

Had been wondering about RT necrosis in conjunction with someone who was on Eliquis, which could make for a new "mass." I know you see CNS. Does RT necrosis show up all at once 4 years later much (in patients who are still around)?

If it's blood you should be able to tell that from the MRI (T1 and T2* or SWI).

I have seen RT necrosis start years after SRS several times.

I use bevacizumab as a last resort. That is symptomatic, convinced it's RT necrosis, etc... Bev has a lot of its own issues.

 

[TheWallnerus]

We are thinking a suspicious spot 5 years out from initial brain involvement from small cell is recurrent small cell? That would be quite a weird natural history for small cell. Not saying impossible, just kind of one for the record books though maybe. Would definitely have my best neurorads guy look at an MR SPECT. I’m no Neuronix but I bet SRS to a brain radionecrosis focus is probably infaust.

 

[Neuronix]

We are thinking a suspicious spot 5 years out from initial brain involvement from small cell is recurrent small cell? That would be quite a weird natural history for small cell. Not saying impossible, just kind of one for the record books though maybe.

Immunotherapy is driving this. Not everyone responds, but I've had some long-term extensive stage SCLC survivors with atezolizumab and friends. it's a good thought though--definitely been sent a few cases over the years for brain mets that turned out to be a new primary, gliomas, or some other weird thing.

One thing to consider, if patient started immunotherapy or changed immunotherapies recently, this can certainly be pseudoprogression.

Would definitely have my best neurorads guy look at an MR SPECT. I’m no Neuronix but I bet SRS to a brain radionecrosis focus is probably infaust.

Now that I've looked up "infaust" (I'm no pinniped!), I agree. Throwing "fuel on the fire" is what I tell patients will happen if I re-irradiate RT necrosis. The right imaging study here is institution specific, with no clear data that one is better than the other. If it's not in a critical location, I let it get to 1 cm or more before going down that route, because nothing is great when it's tiny, and small areas of RT necrosis will often just burn out on their own anyway.

 

[OTN]

I would get an MRI with perfusion - I've had better luck with those to investigate recurrence vs. necrosis compared with MR-SPECT. I would guess necrosis in this case.

 

[MidwestRadOnc]

There are so many in the community who would just circle the spot and SRS without a second thought. You think a bridge oncology once-a-month doc or the random "incident to" locums of the week is going to go through the trouble to coordinate with neurosurgery, med/onc, and/or neurorads to properly work this up and treat?

Sorry, still have a hangover from the supervision discussion.

 

[Ray D. Ayshun]

There are so many in the community who would just circle the spot and SRS without a second thought. You think a bridge oncology once-a-month doc or the random "incident to" locums of the week is going to go through the trouble to coordinate with neurosurgery, med/onc, and/or neurorads to properly work this up and treat?

Sorry, still have a hangover from the supervision discussion.

Probably easiest and most lucrative, but patient asymptomatic. Doesnt really even look like a met. Aforementioned stuff re biology. Just gonna reimage in 4 weeks.

 

[Neuronix]

There are so many in the community who would just circle the spot and SRS without a second thought. You think a bridge oncology once-a-month doc or the random "incident to" locums of the week is going to go through the trouble to coordinate with neurosurgery, med/onc, and/or neurorads to properly work this up and treat?

Sorry, still have a hangover from the supervision discussion.

And... You've just justified the academics advising these patients not to be treated in the community.

You said it! Not me! Everyone throw your rotten tomatoes at them!

 

[OTN]

There are so many in the community who would just circle the spot and SRS without a second thought. You think a bridge oncology once-a-month doc or the random "incident to" locums of the week is going to go through the trouble to coordinate with neurosurgery, med/onc, and/or neurorads to properly work this up and treat?

Sorry, still have a hangover from the supervision discussion.

In all honesty, it depends when- not where- that doc was trained, and I disagree wholeheartedly with the "community" slander here.

 

[thecarbonionangle]

I would get an MRI spec with perfusion after a one month low dose steroid taper if med onc ok or just a month later. If it is still concerning, i would send to surgery. If resection is possible would favor that but at the very least a biopsy to confirm recurrence if it at all possible. Avastin and Boswellia Serrata is a consideration as well.

 

[MidwestRadOnc]

In all honesty, it depends when- not where- that doc was trained, and I disagree wholeheartedly with the "community" slander here.

Slander? Whoa, calm down. My comment was specifically about what ridiculous supervision policies, one way or the other that forces hospitals to use rotating locums or allows JJ to have a random rad onc covering multiple clinics remotely, could result in.

I'd like to believe it's just lazy boomer stuff, but I've seen with my own eyes how complacent people can become, even recently trained ones.

 

[TheWallnerus]

Slander? Whoa, calm down. My comment was specifically about what ridiculous supervision policies, one way or the other that forces hospitals to use rotating locums or allows JJ to have a random rad onc covering multiple clinics remotely, could result in.

I'd like to believe it's just lazy boomer stuff, but I've seen with my own eyes how complacent people can become, even recently trained ones.

Supervision is harmful to patient care?
Supervision is harmful to patient care!

 

[Ray D. Ayshun]

Meh, my experience in the community is very different from my experience at an NCI-designated cancer center. I now understand some, but not all, of the lamented OSH decisions.

 

[OTN]

Slander? Whoa, calm down. My comment was specifically about what ridiculous supervision policies, one way or the other that forces hospitals to use rotating locums or allows JJ to have a random rad onc covering multiple clinics remotely, could result in.

I'd like to believe it's just lazy boomer stuff, but I've seen with my own eyes how complacent people can become, even recently trained ones.

You're right, it was written down so it should have been libel.

 

[Palex80]

Is the patient on IO perhaps (for extracerebral disease)?

Some brain, pre-irradiated lesions can flare up on IO. There are some reports saying that IO induces some kind of vasculitis-like reaction within irradiated lesions, leading to false-positive imaging findings.

 

[RSAOaky]

All, wondering about precedence for this. I haven't treated this patient before, but to sum up, Extensive stage small cell initially with 2 brain mets. 30 Gy in 10 fx WBRT in March of 2019. Left cerebellar progression in May 2020 for which he got 18 Gy x 1. Since that time, he's been stable until recently when he had evidence of progression in the left cerebellum. Not rushing into anything, as I'm not entirely convinced this represents recurrent disease, but mostly curious if anyone has had a similar situation, and has re-srs'd something in someone who also had WBRT.

It's pretty unusual to have a recurrence this far out. Get a short interval MRI. Can also fuse your SRS images and see if it's contained within the relatively high dose region or outside of what you'd expect to necrose.

 

[drmg5000]

Get an MRI Perfusion scan and make sure it's not radiation necrosis

 

[evilbooyaa]

Probably necrosis that far out IMO but you won't know for sure. If only site of disease would consider neurosurgical resection if patient healthy.

If extracranial disease present then re-MRI in 6 weeks. Consider Boswellia.

 

[cmw021]

Agree with short interval MRI with perfusion as mentioned above.

If ends up looking like recurrence in a patient with a decent ecog and limited extra cranial disease, given the local failure rates with resection alone curious if anyone would consider preop SRS here? Could treat to GTV without margin, fractionate as mentioned above, consistent with PROPS-BM study (not a re-irradiation study, just borrowing from the approach). Resect the tissue at highest risk for necrosis?

Risk Factors for Progression and Toxic Effects After Preoperative Stereotactic Radiosurgery for Resected Brain Metastases

This cohort study examines preoperative stereotactic radiosurgery outcomes and prognostic factors for patients with resected brain metastases.

jamanetwork.com

 

[Music Man Stan]

I'm surprised more people aren't asking you how you kept a guy with extensive stage small cell with brain metastases alive for 5 years. I think 100% of my small cell patients with brain mets are dead within 2 years

 

[TheWallnerus]

I'm surprised more people aren't asking you how you kept a guy with extensive stage small cell with brain metastases alive for 5 years. I think 100% of my small cell patients with brain mets are dead within 2 years

I was asking it, but in a roundabout way, as I am most oft wont to do.

At two years, given ES-SCLC w/ whole brain for brain mets, the expected chance of being alive is at best roughly less than 1 in 20... (the reason PCI works? It's not prophylactic; it's treating subclinically present brain mets):

Now, what is the probability of being alive at ~1800 days (~5y) if small cell brain mets were present at day 0, irradiated... twicely!, and smoldering in the same spot for the next ~1799 days??? It boggles my brain. Why I said "one for the record books."

 

[HolySmokes]

I'd like to believe it's just lazy boomer stuff, but I've seen with my own eyes how complacent people can become, even recently trained ones.

I completely agree - I don't think community docs are bad (I am one!) but I have seen firsthand how absolutely lazy they can/will get if not held accountable or self motivated. The number of mistakes I've caught from my partners could fill tomes.

 

[RadOncDoc21]

Are these docs doing any sort of peer review? It’s kinda easy to review plans remotely with other docs.

 

[drowsy12]

Are these docs doing any sort of peer review? It’s kinda easy to review plans remotely with other docs.

peer review?

we're talking about peer review?

peer review?

(imagine in Allen Iverson voice, regarding practice)

 

[Radonky]

I would probably do short interval MRI, if continued progression (increased edema, symptoms, or enhancement) would get MR spect, and chat with neurosurgeon if they would be willing to resect based on findings suggestive of disease if amenable, and 25x5 to postop cavity if path + for small cell, or observe if it just shows treatment effect/ RT necrosis

 

[evilbooyaa]

I would probably do short interval MRI, if continued progression (increased edema, symptoms, or enhancement) would get MR spect, and chat with neurosurgeon if they would be willing to resect based on findings suggestive of disease if amenable, and 25x5 to postop cavity if path + for small cell, or observe if it just shows treatment effect/ RT necrosis

I mostly dislike post-op SRS, but do it begrudgingly because that's the expectation in patients who get a brain met resected.

But, I really, really dislike post-op re-SRS. If the patient gets a surgery that demonstrates active disease, just let it recur focally before you put them at increased risk of toxicity with re-RT. Mahajan trial showed improvement in local recurrence without any effect on OS... 43% of being recurrence free with surgery alone.

One thing when you're talking about 5-15% risk of late G2+ toxicity, but another when that goes up to > 25%, IMO.

 

[radiation]

If you are a radiobiology purist, since small cell has no shoulder for repair, you could argue to do focal fractionated treatment to a lower dose. Theoretically the total number of fractions may matter more than total dose, so you can probably do something like 20 gy/10 fractions if you really want to retreat safely

 

[RadOncDoc21]

If you are a radiobiology purist, since small cell has no shoulder for repair, you could argue to do focal fractionated treatment to a lower dose. Theoretically the total number of fractions may matter more than total dose, so you can probably do something like 20 gy/10 fractions if you really want to retreat safely

10 fractions!!! Well… it’s reasonable only with protons!

 

[Neuronix]

10 fractions!!! Well… it’s reasonable only with protons!

*Laughs in craniospinal*

PS: I've seen enough SCLC mets not behave like they're supposed to that I totally ignore the supposed sensitivity of SCLC metastases.

 

[TheWallnerus]

*Laughs in craniospinal*

PS: I've seen enough SCLC mets not believe like they're supposed to that I totally ignore the supposed sensitivity of SCLC metastases.

Very weird response but I love it

 

[NotMattSpraker]

There are so many in the community who would just circle the spot and SRS without a second thought. You think a bridge oncology once-a-month doc or the random "incident to" locums of the week is going to go through the trouble to coordinate with neurosurgery, med/onc, and/or neurorads to properly work this up and treat?

Sorry, still have a hangover from the supervision discussion.

Community, what about the ASTRO board?

No breast is safe!