Getting more questions than answers (FSR approach)

[Bomberman]

Hello, as I am researching into my options I am able to solve some of my questions, but I keep coming up with more questions than answers. I'm not sure if anyone can help me with these:

1. What are the chances of regrowth, and if there is regrowth what needs to be done? What is the success of the 2nd treatment now that there is a scar tissue existing which is different from the tissue before.
2. What are the risks if the radiation is close to the brain stem?
3. Will it affect me from flying?
4. Is an approach by just radiating the bulky area instead of the nerve area feasable? And would that provide better outcomes?
5. Does spreading out the radiation into more treatments increase the chance of saving hearing? I read that each pass costs over 10g.

Thank you

[tdlight]

You are experiencing what most have experienced in your search for answers; every doctor has an opinion and your lucky if you can find two that agree.  I don't know that any of your questions can be answered definitively except maybe number 3 (and I don't have the answer).  I will take a shot at 4 and 5 and I suppose a little of 2 since it's related to 4.  (These are just my interpretations of what I have read and been told.)

4. Is an approach by just radiating the bulky area instead of the nerve area feasable? And would that provide better outcomes?

When the doctors (computers) create the treatment plan for a particular tumor one of the goals is to miss as much of the "important stuff" as possible.  Yeah, it's all important stuff in there but there is some that is more sensitive to radiation, like nerves. My doctor said to imagine they are painting the tumor with radiation; they try to only paint the tumor but obviously as they access the tumor they need to pass through other tissue with that paint brush.  They try very hard to miss the nerves that AN's are close to or growing on.  I assume the same can be said for the brain stem (a big bundle of nerves) as well as other nerves.  I know they try to avoid hitting the cochlea directly as it is sensitive to radiation.  One of my docs said sometimes people see flashes of light if the beams get too close to the optic nerves; I thought that was kind of interesting.  The whole reason they come at the tumor form all those different angles is so they avoid exposing healthy flesh to too much radiation; it's just where all those beams converge that gets the full dose.

5. Does spreading out the radiation into more treatments increase the chance of saving hearing? I read that each pass costs over 10g.

This is one area where you will not find agreement among doctors.  I read at least one study and was told by at least two of the six doctors I consulted that there was some evidence that a fractionated (multiple treatments) approach offered better hearing retention.  Fractionated treatments seem to have the same effectiveness, so that amount of evidence was good enough for me to chose a fractionated approach which also lead me to Cyberknife over Gammaknife (Gamma being a one and done only).  I am six months post treatment and my six month audiogram showed no change in hearing.  I am told I will eventually lose more hearing but will it be better than if I had a single dose, who knows?  If I were paying the full cost and it came down to $10K vs $30K I think I would go with the single shot; the evidence doesn't seem that strong.

I hope that helps.

[PaulW]

1. What are the chances of regrowth, and if there is regrowth what needs to be done? What is the success of the 2nd treatment now that there is a scar tissue existing which is different from the tissue before.
Depending on so may factors success rates appear to be between 85-95% at 10 Years
Outcomes from surgery after surgery or surgery after radiation are pretty much identical in result.

2. Depending on the size of the tumour the risk could be virtually non existent, to a very small risk..
Tumours over 3cm pose a bigger risk. A very small percentage of the population are sensitive to radiation
and tumours over 3cm are a significant risk to them.

3. Will it affect me from flying
No...

4. Is an approach by just radiating the bulky area instead of the nerve area feasable? And would that provide better outcomes?
As the tumour is a nerve tumour its difficult to avoid the nerve. While we might imagine radiation to have a really sharp beam like stage spotlight. Its much closer to a beam from a $2 flashlight
Typically the radiation has a hot spot in the middle, and the edge is not crisp, but has a 2mm blur on each side. So no they cannot avoid the nerve, but some do make a slight allowance for it, and give it slightly less radiation. The less radiation hitting important stuff is good.

5. Does spreading out the radiation into more treatments increase the chance of saving hearing? I read that each pass costs over 10g.
There is very little evidence showing that fractionation provides better hearing than single dose. The best Gamma Knife figures match fractionated Cyberknife.
Better hearing statistics are often linked to patient selection, smaller tumour, good hearing already, younger age, etc
Accuracy of the equipment does seem to play a role, as less radiation to the cochlear is linked with better hearing preservation.
Fractionation did seem to have a slight edge at the 3-5 year mark, but the results at 10 years are remarkably similar to GK.
A disadvantage of fractionation is that you will receive a lot more radiation which means you are less likely to be able to have a second radiation treatment and in theory expose yourself to a higher cancer risk.
My personal non medical view is that if there is an advantage with fractionation, then going beyond 3 fractions hold few benefits.