Jussi from Finland - Dx 2008 - 30.3.1991 - 23.8.2019 R.I.P.

[arojussi]

There actually is simple explanation for necrosis. In Finland they first planned to use doses of 14-15 grays. I said that wouldn't be enough, so they simply added doses to maximum. Meaning that over 2cm met received 20 grays and smaller mets 30 grays. I dont remember exactly. I believe this is key reason behind necrosis. In China doctor has experience with asps, so he choose dose of around 20 grays to avoid necrosis he also knew that in asps margins have to be close to avoid necrosis. Yes gamma knife is more accurate than linear arc, but that wasn't the only difference.

[arojussi]

Of course radiation necrosis is late compltcation, so it is still way too early to tell if I will have it again.

[arojussi]

I am going to think out loud here again: I found one study comparing gamma knife and linear arc. Linear arc results in significantly higher normal brain tissue radiation dose. After I found that out, I knew that even though linear arc wasn't reasonable to treat all my brain mets, gamma knife or cyber knife could do the trick. Gamma knife uses more heavy head frame, so treatment with it is little more uncomfortable than treatment with cyber knife, but when you are radiating your brains you want your head to be as still as possible. Doctor at the private hospital didn't mention the difference between gamma knife and linear arc and all public hospitals recommended whole brain radiation, so it took me a long time to figure this out. Linear arc treated mets also regrow more often than gamma knife treated mets (difference wasn't statistically significant.) So for asps brain mets gamma knife would be my first choice. For big tumors over 3cm linear arc or surgery could be only option. I would choose surgery.

[D.ap]

Hi Jussi
Lots of interesting thoughts .
So your next scan will be 2 months or 3?
What dose of sutent are you on?
Renal cancer has had response in brain metastasis

https://www.ncbi.nlm.nih.gov/m/pubmed/18214028/

There's an interesting read on why the neurcrosis happens, most times with higher doses and it's because of VEGF leakage caused by higher doses of radio ? So the useage of anti VEGF is one of the suggested remedies to combat the high protien damage / neucrosis/ , as well as edema .

The article was focused on using Avastin for slowing down necrosis progression


https://cancercompass.com/message-board ... 3613,0.htm

Also with primary glioblastomas(higher grade compared to ASPS possibly?)
It talks of using blood flow comparisons with MRI , DSC, scanning data has been helpful in diagnosising progression verses neurcrosis


"Barajas et al attempted, in a study of 57 patients, to determine whether T2-weighted dynamic susceptibility-weighted contrast material-enhanced (DSC) MRI can differentiate radiation-therapy-induced necrosis from glioblastoma multiforme. They found that mean, maximum, and minimum relative peak height and relative cerebral blood volume were significantly higher in patients with recurrent glioblastoma multiforme than in patients with radiation necrosis. In addition, they determined that mean, maximum, and minimum relative percentage of signal intensity recovery values were significantly lower in patients with recurrent glioblastoma multiforme than in patients with radiation necrosis.3"

[Jorge]

I'm so glad to hear there is no progression! Happy for you!

As for the scan accuracy, it is complicated to non-professionals. I try to learn about the resolution of the MRI scan, but still not very clear about it. My concern is if the regular scans are done in high resolution (thin slide thickness and slide distance?) or in the same scanning conditions like Gama Knife. If not, it's not easy to compare the latest scans and evaluate the Gama Knife result.

For the difference of LINAC based radiosurgical (what you had before) and Gama Knife, I don't know about LINAC based radiosurgical, is it so called X-Knife? But I know something about Gama Knife and Cyber Knife:

Gama Knife.jpg (13.54 KiB) Viewed 3703 times

201 Gama Rays go to the target from 360 degree, so the energy at the target is way higher than normal tissue. I ever saw the Gamma Knife planning on the computer before the treatment. It's like a stereo net of rays over the head. We always request the treatment planning of each Gamma Knife for record. In the planning, there is very little margin to the target tumor(size from a few mm to 1.5cm)--the line is just drawn along the outline of the tumor.
The theory of Cyber Knife is very similar to Gamma Knife. The difference is the tumor targeting mode. In Gamma Knife, a head frame is secured into the skull for accurate positioning. In Cyber Knife, there is a CT scan before each treatment to match up the face bone with the previous scan for positioning. Therefore, Gamma Knife is more accurate than Cyber Knife for small tumor.

[Olga]

CyberKnife is a Robotic Radiosurgery system consisting of a light weight Linear Accelerator (LINAC) attached to a Robotic arm, it is frameless, uses X-Rays. It uses Internal gold fiducials (seeds) that are necessary for tracking and are planted in advance. As I understand, in the motionless organs they use some close located bone for the mapping, without fiducials.

Gamma Knife is another modern-day Stereotactic Radiosurgery system, delivers as many as 201 beams of Gamma Radiation precise to the sub-millimeter level of the targeted area trough the frame fixed (screwed) on the patients head.

different types of the stereotactic radiosurgical treatments here:
http://www.cyberknife.medanta.org/cyber ... amma-knife
As I understand, GammaKnife is still the most precise and reliable brain mets treatment technology available today.

[D.ap]

Jussi
On another note and back to necrosis , I was re reading our scan discussion and reminded how laser treated lung tumors are assessed for necrotic / inactive tumors are evaluated by the using of no contrast / contrast imaging.

http://www.cureasps.org/forum/viewtopic ... t=30#p6399

Also metabolic imaging is useful as well ,
as I would venture to say ASPS mets are more active than lung etc?

[arojussi]

Thanks for information.

[arojussi]

So they tested my tumor sample for mutations and found none. Result doesn't make any sense basically my asps doesn't look like cancer at all. Based on this I am not able to attend any trials.

[D.ap]

Hi Jussi
The cerebellar met was analyzed ?

[arojussi]

Yes

[D.ap]

Remind us of how the surgically removed 2cm? tumor was analyzed ? What method ?
They ran prior tests to determine the effectiveness of pazo and Keytruda on a portion of that tissue correct ?

There's some interesting write ups on liquid biopsies worth reading

https://bmccancer.biomedcentral.com/art ... 016-2992-8

[arojussi]

Sorry I don't have any idea how they tested that tumor sample. Also Chinese neurosurgeon believes that new brain tumors appeared slowly during time I was on keytruda and pazo. It is certain that my cancer progressed when I was on both pazo and keytruda, so neither of these drugs isn't working anymore. Saddest part is that they didnt wound any mutations from my tumor sample, so immunotherapy of any kind is very unlikely to work for me, because immune system needs neo-antigens to recognize cancer as foreign.

About liquid biopsy: private hospital offered to do it for me instead of srs. Doctor gave me example of very good result achieved in breast cancer. I am worried that mutations seen in blood might be from my lung mets and not from brain mets. All I need is treatment for brain mets. Lung mets can easily be cryoablated.

[D.ap]

Hi Jussi

Is it possible that using the blood biopsy or even from the lungs might give enough info to target brain tumors ?
The brain tumors showed some necrosis ? Some effects from the TKI Pazo?
All tumors have some original mutations is my understanding ..even as early as the primary tumor ?

[D.ap]

Jussi
What do you think and your oncologist ?