GK retreatment anyone?

[LBB]

I am looking fro anyone who has had GK to an AN and then had to be retreated.

[phantagrae]

Has your AN started to regrow?

From what I understand, they won't do a second radiation treatment if you've been treated before, but I there are others here who know more about that than I do.


Good luck.

[mindyandy]

I don't know anyone on this forum but on FB there is an AN group that has at least 1 maybe 2. 

[jsanders1379]

people were posting about this just today on the Facebook page

[nftwoed]

Hello;

   Need to 'respectfully disagree' about re-treatment of previously irradiated ANs. To my knowledge some will re-treat GK. I've never heard of re-treatment of CK or FSR.
   I believe if one has a surgical Tx regrowth, historically, GK is the next step, then surgery again if the 2nd GK Tx fails.

Has your AN started to regrow?

From what I understand, they won't do a second radiation treatment if you've been treated before, but I there are others here who know more about that than I do.


Good luck.

[phantagrae]

Hello;

   Need to 'respectfully disagree' about re-treatment of previously irradiated ANs. To my knowledge some will re-treat GK. I've never heard of re-treatment of CK or FSR.
   I believe if one has a surgical Tx regrowth, historically, GK is the next step, then surgery again if the 2nd GK Tx fails.

Has your AN started to regrow?

From what I understand, they won't do a second radiation treatment if you've been treated before, but I there are others here who know more about that than I do.


Good luck.

I'm just speaking from what I think someone here posted, having to do with how much radiation one is exposed to, etc.  Like I said, obviously others know more about it than I do.

[nftwoed]

Hi;
   In thinking, I believe I do recall reading from another group a couple years ago, a Hopkins Dr. did agree to re-perform FSR about 13 years after the first Tx. The 1st Tx had to be in the early years of FSR. Too bad FSR didn't really catch on for AN as has excellent theory behind it! Maybe it would have kept advancing if Dr. Williams, of JHH, had lived and Lederman didn't have his legal troubles?
   I wonder if I'm wrong, but FSR does seem more highly practiced by oncologists anymore? Thoughts, anyone?

[PaulW]

FSR was originally designed as a work around for the lack of accuracy of the machines.
They always wanted to do single session.

By giving 25-30 Doses even if the machine was only accurate to +/- 5mm, due to chance and the Normal distribution curve most of the radiation would end up where it was supposed to go. This effectively increased the accuracy of the treatment through probability.
It comes at the expense of higher total radiation exposure, and a much longer treatment time.

The problem with FSR is that your receive much more radiation, around 50Gy for the treatment instead of 13Gy
You also get the radiation over 25-30 days.

There is a concern over success of radiation treatments when they occur over that length of time.

For instance if a cell divides on Day 15 the new cell will never receive enough radiation to destroy it by Day 30.
Only all of the existing cells from Day 1 would have definitely received enough radiation.
So any cell replication during the treatment maybe the source of regrowth.

If you have Single Session CK or GK they can radiate a second time. Typically I believe with 10 Gy
If you have had FSR you would have received around 50 Gy and the risk of receiving further radiation is considerable. 

One of the advantages of Radiosurgery over radiotherapy is that it can be performed a second time

Its over these concerns that many no longer perform the treatment

 
 

[Jim Scott]

Paul ~

I underwent FSR in 2006 so I cannot respond to the question of whether it is still used routinely used on AN patients by oncologists.  However, I can comment that my neurosurgeon wanted me to undergo the FSR on a debulked AN that had it's blood supply severed during the (retro) surgery as part of my AN treatment plan.  My AN symptoms disappeared immediately following the surgery.  90 days later (as part of a plan) I received a total of 27 Gy over 26 days.  I suffered no side effects from the radiation.  Over the next two years the remaining tumor responded by swelling then showing necrosis.  To date, (7 years later) I'm doing great and haven't experienced any symptoms of re-growth. 

One caveat: I was 63 at the time of my AN surgery and radiation so that was a likely factor in the doctor's decision to employ FSR.  Due to concerns regarding radiations effects in the long term, I doubt he would have recommended it if I had been 20 or 30 years younger.  However, the fairly remote possibility of the radiated tumor turning malignant sometime in the future was not a real concern for me but I can understand why doctors still harbor that concern for their AN patients. 

Jim

[PaulW]

Hi Jim,
I believe going back 20 years ago FSR was the way to go.
Stereotactic radiosurgery was seen as risky.

The one shot nature meant that if you got it wrong there were serious consequences for healthy tissue or the radiosurgery didn't work because too much of the tumour was missed,

This made FSR far safer than early radiosurgery and more effective.

With FSR having such a long track history people see comfort with it and the possible advantages of fractionation were also discovered.

Its still a valid treatment and is often favoured for larger tumours.
But getting FSR a second time isn't done, due to the higher amounts of total radiation received.

It is known that FSR is not as effective at controlling aggressive tumours as Radiosurgery as new cells will be spawned during the treatment. However with AN's and their slow growing nature, this is far less an issue.

Its also know that small AN's remnants left after surgery for hearing and facial nerve preservation mostly don't grow .
Certainly an indicator that a new cell or two probably cant survive on its own after FSR.

I believe the main reason FSR is being used less is cost, profitability for the centre and patient convenience
Older machines from the 80's are gone. Machines from the late 90's have been upgraded.
FSR is now a choice, not a necessity.
Just about everyone can do radiosurgery now, and they do it with the same new machines that deliver FSR.