Radiation accuracy?

[Larry]

here goes, my two bob's worth as well (used to be 20c in OZ before decimal currentcy), anyway, as a patient that has undergone surgery (with not so good results), and is about to undergo FSR, I add the following.

Agree with the expert advce and commentary above, by Phyl and Mark and also add that statistics mentioned on this forum some years ago indicated the odds of GK or FSR turning the AN malignant is 1 in 10,000. The mortality rate from surgery is 1 in 500. These stats are pretty generic but have not been disputed by various Doctors that i have spoken to.

My Doc, and backed by a second opinion, recommended FSR coz my growth has started to hit the brain stemm. the single burst may also damage some sections of the brain.

The critical questions to ask of the radiation people are:

The experience of the technicians
Is the software of the machine up to date
What are their specific stats re facial nerve damage and the AN turning malignant

I chose radiation because I will not go through the surgery procedure again due to the complications i have had from it.


Laz

[marion]

After reading all the discussion about CK vs GK, I have to share my story because I am also in the process of deciding which radiation modality is better for me.  I reside at the SF Bay Area.  After AN dx, I had a consultation with Dr. Adler at Stanford, he offered CK to me without any reservation but he could not provide any statistics on outcomes after CK just saying that this treatment can preserve my hearing. I also found out that he was the founder of the CK company, Accuray; I believe he presents conflict of interest with this recommendation. This is the reason he and Dr. Chang are all for CK.
 Now I am exploring GK option at UCSF.  UCSF do offer both CK and GK at their radiation oncology facility,  but the doctors prefer using GK in my case, and they offer me statistics on every possible side effects.  I do trust my doctors at UCSF.
 Like some of you indicated: this radiosurgery treatment is a matter of personal choice.  GK has existed for more than 20 years with lots of data supporting the tumor control rates and side effects etc, however, CK only has been available for about 5-6 years, therefore long term effect is unknown.  I have decided to select GK as my treatment plan, hope you bless my choice. Thank you.   

[ppearl214]

Marion,

Congrats on honing in on your decision. I think you know by now that decisions made here are supported by us all as you have to do what is best for you and your individual situation.

I do, however, want to clarify about CK... it has been around a lot longer (Mark, here, was treated by CK approx 8 yrs ago and see this link for further, corporate info:  http://www.accuray.com/CorporateInfo/History.aspx). As you can see, it's acceptance has grown tremendously, worldwide. Although not noted, the UK, this month, is also opening their first CK site in Central London.  Just FYI).

Sending wellness wishes.
Phyl

[Tisha]

Marion,

I had CK on 1/12 of this year.  I'm not sure why Dr. Adler didn't give you any statistics.   They are one of the few that actually have statistics out there on CK.  It's not hard to find them if you just do an internet search.  Plus, they told me new statistics will be forthcoming soon, and Dr. Medburry on the Cyberknife forum also mentioned this.

The statistics:    75-80% hearing preservation at levels 1 and 2.  Most of the time, people who go in with good hearing are the ones that maintain it.  The 20% that lose hearing, average a 12db loss.  Very few people lose it altogether. 

Tumor control of 98 - 99% (shrinkage or no growth), Basically no facial paralysis 99+%, Balance issues:  2/3 stay the same, 1/3 get better, 5% get worse.  Dr. Chang delivered these stats to me and several other people here who have called and /or had CK in the last month.

Dr. Adler is the inventor of CK.  It doesn't surprise me that he would probably own stock in Accuray.  Since he invented this maching, it only stands to reason that he prefers this.  Dr. Chang is a neurosurgeon and does 50-50 surgeries/CK treatments.  If you're tumor is too large for what they feel can be treated by radiation, he's not going to steer towards it.  He can surgically remove it.  I trusted him because he does both.

Yours is the first post I read that just doesn't sound like this group.  I can't speak about Dr. Adler, never spoke to him.  But Dr. Chang left me with nothing but comfort (or as comfortable as one can be) about CK.

I would call and ask for an appt. with him, or call and ask to speak with him.

Good luck.  Tisha

[marion]

Dear Phyl and Tisha,
Thank you for your kind support and clarification.   Yes, I have a sense that the
forum members are in favor of CK; don't know why?   I have communicated
with more than 10 neurosurgeons (Harvard, Pittsbergh, U of Wash, USC, U Chicago and UCSF) besides Alder; none of them recommended CK with my case, (my tumor is small, about 10mm, hearing loss 70%) and two of them recommended microsurgery.  I myself is not against CK, its the team members I feel comfortable with; it turns out I prefer GK.  Thanks again, Marion

[Mark]

Marion,

good luck with your GK treatment at UCSF. Found your post about Dr. Adler not being able to produce statistics on CK which is perplexing to say the least.

Here is one after a 30 second google search

http://cat.inist.fr/?aModele=afficheN&cpsidt=16907918

Mark

[sgerrard]

hearing loss 70%

I suspect that figure is the reason for less interest in CK. Nothing wrong with doing GK; your comfort level is very important. Congratulations on making the call.

Steve

[Tisha]

Marion,

If I didn't have hearing that was I concerned about CK, I would probably also be as interested in GK like you are.  I also agree you HAVE to have comfort with whoever is treating you.  It looks like you've done your homework as far as talking to doctors.  However, I still am very concerned with the response you had from Dr. Adler.  Did he really tell you they have no statistics or did he just not volunteer any to you?  Did you ask him that specifically?  Just trying to get a handle on what happened and the disconnect there between you and he.

I found the post where you are having GK.  Good luck with the procedure!  Let us know how everything went.

Tisha

[marion]

I am an epidemiologist, no one can fool me with statistics; I did read the paper Mike refers to.
There are a total of more than 200 cases Stanford have performed on CK, but they only
report 61 cases, why?  What happened to the other 2/3 of cases??   And Stanford have
the CK since 1999, how come they only reported the follow-up for about 3 years??
I am sure this is why Dr. Adler don't want to say much about the statisitcs with me,
because they do not have data on long term effect.
Needless the say, every one of us has to go with our gut feelings and select the best treatment choice.

[Tisha]

Marion,

Those are valid questions, but one that you should put forth to the doctors if you are confused.  First of all, the study is dated 2005 and states that it follows a MINIMUM of 36 months with the average of 48 months.  It started the study in 1999....that means that they went thru 2002-2003, depending when it began in 1999.    It would probably take a year to put together the statistics and have it published, so it's not unreasonable that it was put out no earlier than 2005.   As far as 61 out of 270...well...my guess is that they send out a form for prior patients to fill out and like most people....the majority don't feel the need to.  Even more specifically, most happy people don't feel like filling out their forms, they just go on with life.  It's usually ones that have something to complain about that are more than happy to fill out a form about their experience.  Just my opinion on that.  Nobody pays these people for statistics, so I highly doubt if they are going to take much time to follow up with phone calls, etc. to get people to respond.  Secondly, I really really doubt that Adler, Chang et all are trying to fool the general AN public with misleading data. 

They are coming out with a new study.  They have also told patients that the new longer term studies show that perhaps hearing may decrease over time after the 3-4 year period by a few db's. 

Tisha

[sgerrard]

It does seem to me that radiation treatment is often presumed guilty until proven innocent, a standard which it does not deserve. If you examine the physics, the radiation biology, the mechanisms of the machines, and the software used, there is every scientific reason to conclude that GK and CK will produce very similar results. Therefore we should be expecting the outcomes to be the same, and be looking out for any signs that they are not, rather than the other way around. To my knowledge, all indications are that CK is proving to be another good way to deliver radiation treatment.

Steve

[allegro17]

Here is something else I have been thihking and wondering about.  I know that there seem to be a similar set of side effects (with better hearing preservation for CK) with any radiation treatment, due to swelling/dying of the tumor, etc.
Does anyone know if the incidence/intensity of side tends to be lower with, say, 3 shot CK vs. 1 shot GK?  I just wonder if maybe with the GK the tumor would swell more due to being zapped "harder" with a higher dose in one shot as opposed to getting that dose over 3-shots.  I know fractionating is gentler on the surrounding tissue but I just wonder how it, if at all, affects the tumor or chance of side effects like fatigue, dizziness, nausea, headaches, balance, etc.  Is this more just kind of based on the individual/specific tumor and how it decides to react or should it be a deciding factor in treatment choice?
Oh, and one more question
If the tumor stays in my head, as opposed to coming completely out, is there any chance for further damage that it can cause?  Like say if it swells and then stays that size but dies, will my facial nerve function diminish over the years due to pressure from the tumor, even if it's not growing?  Or things like that.  I guess what I want to know is, would there be any reason, other than mental comfort, for me to want the tumor out of my head as oppsed to leaving it in, assuming either treatment would effectively "control" it?
I go to NY on Monday for consultations with two neurosurgeons and 3 GK/neurosurgeons.  It will be my first time talking to anyone about GK specifically, as opposed to cyberknife or Novalis BrainLab.  I'm hoping to have all the info to make my decision by the end of the trip and get something scheduled!   
Thanks SOOOOO so much for all of your help.

Laura

[mk]

Laura,

these are excellent questions.
On the topic of the swelling, it is generally accepted (although I don't know if it has been really proven), that for larger ANs, the potential of swelling with GK is more significant, because of the single dose delivery of the radiation. This is why there is an upper limit with GK (3 cm), whereas no absolute size limit with CK. At least this is what I have been told by the doctors at the Cyberknife forum. When GK is used for relatively large tumors, the radiation dose is typically reduced accordingly, to avoid serious swelling problems.
That beeing said, from an informal review of posts in this forum, I would say that swelling is reported most frequently than not by most of the people who have undergone any type of radiation treatment.

Your second question about the long term effect to the nerves is very interesting too. My (very simplistic) point of view is that the nerves have adjusted during all these years in the presence of the AN. The facial nerve for example has the capability of beeing stretched significantly. Therefore, in the short term there is probably more risk of doing damage by actually disrupting their current state. However, what happens in the long term seems much more uncertain - for example I have heard that the balance nerve continues to deteriorate. I would be very interested to hear what the doctors you consult with have to say on this issue, so please do ask them and let us know.

Marianna