ANA Discussion Forum

Pre-Treatment Options => Pre-Treatment Options => Topic started by: Bomberman on September 25, 2016, 09:17:23 pm

Title: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on September 25, 2016, 09:17:23 pm
I've done a good amount of research now and have started to form conclusions. I've talked to 3 neurosurgeons, 2 radiologists (Linac and CK), 1 GK technician and I'm starting to conclude the main difference between the 2 approaches. These are my thoughts on surgery vs radio.

Surgery: good for those who prefer long term tumor control/removal
Radio: good for those who prefer short term hearing preservation (long term is unknown)

Surgery is better for those who don't want to deal with anything down the line, because it can remove everything, or at least give you a chance for GK down the line which is pretty good one shot procedure.

Radio is better for hearing preservation because the numbers support higher rates of hearing retention. However data is only available for the last 10 years and the trend seems to be going downhill over time. At the same time it doesn't have good long term control because larger tumors have higher chances of regrowth. Secondly, if there is regrowth, further radiation cannot be done because effects of previous radiation is already there. There is also a tiny chance of new tumors resulting from the radiation. Thirdly, the resulting scar tissue complicates future surgery because it no longer has the same characteristics as an untouched AN such as softness, and delineated edges. Someone previously asked, what is the elephant in the room. I think this is it.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Blw on September 25, 2016, 11:22:13 pm
There are many many variables that you have to account for with both procedures, so you have to be careful to make sure you are comparing apples to apples. Tumor size is important. Location. The nerve it originated from. All things being equal, the two approaches have very similar outcomes. There is an upper size limit beyond which radiation is not recommended, and if the tumor is on the facial nerve, surgery is most likely the second choice. The key component is tumor control. Surgery can often get it all out, then you are done with it, but it can also fail and you get regrowth. Surgery can also preserve hearing depending on strategy, but it can also destroy it. True, that a radiation failure makes surgery harder, but it does not always rule out a second radiation. Some people are not concerned by surgery and want it all out and over with. Others do not want the invasiveness of surgery. The best approach is get as many opinions as you can, then when you decide on a strategy, go to the absolute best doctor that you can, even if you have to travel. Keep in mind surgeons want to operate and radiators want to radiate. Try to find one person that does both so that you can reduce bias. Read as much as you can here, and go through the two different sections; surgery and radiation. Lots of pros and cons. Also, some misconceptions can be corrected. If you know how to use PubMed (the NIH literature search site), go there and use the review function in your searches so you can read large clinical studies--reading single case reports doesn't tell you much and there are thousands. Many journal articles do not allow public access, but many do if they were funded by NIH.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Citiview on September 26, 2016, 02:49:54 pm
How large is your AN?
I agree with BLW (the whole post) but especially choose the best doctors. Now is the time to be discriminating and get the best team.

I think hearing preservation is hit or miss. Some people lose hearing in middle fossa surgery (supposedly the best for preservation). Others have very large tumors and somehow retain hearing with surgery. I think there is a lot they don't know about hearing preservation and the science is constantly evolving.

I notice there are a few centers that are attempting cochlear implants with acoustic neuroma surgery. I'm sure it's in the beginning stages and experimental.

Good luck.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: rupert on September 26, 2016, 07:00:11 pm
   A couple of things.  Your post contains a lot concerning hearing preservation.  Hearing preservation and AN's don't seem to like each other.  I'm sure I sound like a broken record if you read my other posts but, chances are that no matter what procedure you have done your hearing is going to go away some or all.  That's just the way it is with AN's,  they are hearing killers.   Some people do come out pretty good but, most will not.  The Docs are certainly trying,  and new techniques happen all the time.  Maybe someday there will be better outcomes.
   As far as your thoughts on radiation.  I think some of your conclusions are wrong.  After GK or CK treatment the chance of regrowth is very slim.  Exactly the same as surgery by the way. The tumor may,  or may not be any harder to remove if need be.  Some of the best doctors say that it makes no difference.  Some are naturally harder to remove regardless of treatment.  GK has been around a long, long time and there are certainly long term studies on it.  Hearing preservation is kind of a new thought as far as treatment regardless of radiation or surgery. Again, that's a new concentration the doctors are constantly working on but, not much success yet.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on October 02, 2016, 05:35:46 pm
If you know how to use PubMed (the NIH literature search site), go there and use the review function in your searches so you can read large clinical studies--reading single case reports doesn't tell you much and there are thousands. Many journal articles do not allow public access, but many do if they were funded by NIH.

Can you tell me what is the review function?
Anyway to get private access?
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Blw on October 02, 2016, 07:07:53 pm
The pub med site is here:
<https://www.ncbi.nlm.nih.gov/pubmed/>

Copy and paste this in
vestibular schwannoma

hit search

On the left column, top, is a heading that says article types. Select review

To read the summary of each article click the blue links. If the article has a button on the right that says PMC full text, you can read the whole article.

As a shortcut, after selecting review, there is another heading under article types called text availability. If you click free full text, only the ones that are free and have the whole article will appear.

If you want to increase specificity, use "and" as a modifier, such as Vestibular schwannoma and radiation. You could also do vestibular schwannoma and gamma knife. Also, vestibular schwannoma and surgery.

There are ways to make it even more deteailed, but start with this and you'll learn as you go along.


Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Blw on October 02, 2016, 07:16:53 pm
A minor point that people who are really concerned with hearing might consider. As was noted, hearing an ANs don't go well together and the norm is to have much worse or no hearing after it is all over. With surgery, you could wake up without hearing if they cut the nerve, and sometimes they tell you that going in. With radiation, assuming you are starting with reasonable hearing, it can take years to lose it--not a good outcome, but gradual hearing loss helps your brain adapt to the changes easier. I think some of the numbers quote a rate of 50% useable hearing after 5 years. I'd take that in a minute.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on October 08, 2016, 12:26:13 pm
I followed Blw's advice and I've compiled numbers between FSR and retrosigmoid surgery. They take into account regrowth and salvage therapy chances.

                                        Retrosigmoid   FSR
facial nerve perservation   96.7%             91.1%
hearing preservation         24.6%             46.9%

Calculations:
96.7%:
Facial nerve preservation stands at 97% http://thejns.org/doi/pdf/10.3171/2011.7.JNS101921. n=383
Regrowth rate of 13.2% http://thejns.org/doi/pdf/10.3171/2011.7.JNS101921. n=383
Salvage GK 94.6% (.94/.994 post op 50months) from https://www.ncbi.nlm.nih.gov/pubmed/25065850 n=159
0.97x86.8 + 0.946x13.2 = 96.7%

24.6%:
19.2% hearing preservation from https://www.ncbi.nlm.nih.gov/pubmed/25065850 n=159 supported by https://www.ncbi.nlm.nih.gov/pubmed/23749017 n=32
Regrowth rate of 13.2% from above
Salvage GK of 60.4% = 11.6/19.2 https://www.ncbi.nlm.nih.gov/pubmed/25065850 n=159
0.192x86.8 + 0.604x13.2 = 24.64%

91.1%:
Facial nerve preservation stands at 94% from https://www.ncbi.nlm.nih.gov/pubmed/26508404
There is an 8% chance tumor is not controlled https://www.ncbi.nlm.nih.gov/pubmed/26508404, supported by https://www.ncbi.nlm.nih.gov/pubmed/22921979, and https://www.ncbi.nlm.nih.gov/pubmed/21353158
Salvage surgery preserves facial nerve at 57.4% (0.5x0.795 + 0.857x0.055+0.857x0.151) from https://www.ncbi.nlm.nih.gov/pubmed/21897324 n=73
0.94x92 + 0.574x8 = 91.1%

46.9%:
Hearing perservation is at 51% for large tumors https://www.ncbi.nlm.nih.gov/pubmed/25077322 n>4000 patients
Other studies show 0.43 = (24+60)/(85+109) from  https://www.anausa.org/component/docman/doc_download/448-2014-patient-survey-report-final?Itemid=357 n>1000
Ck reports 77% https://www.ncbi.nlm.nih.gov/pubmed/19751871
57% from https://www.ncbi.nlm.nih.gov/pubmed/19303780 n=254
Interesting that class 2 Koos is 47% https://www.ncbi.nlm.nih.gov/pubmed/15179283 n=1000
8% chance tumor is not controlled.
Salvage surgery makes hearing preservation impossible: https://www.ncbi.nlm.nih.gov/pubmed/23177377 n=19
0.51x92 + 0x8 = 46.9%

Notes:
I tried to cater this to large ANs (mine is 2.9cm).
Regrowth rate of surgery is a little bit higher because Dr. Sisti tends to be on the conservative side in saving nerves and leaving more behind.
The numbers for radio will go down over time as the longer it is, the trend is the higher the chances for regrowth and so far we only have less than 10 years of data.
Let me know if you see some numbers that can be more accurate.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: rupert on October 08, 2016, 07:54:08 pm
Sorry, I can't make heads or tails of your post.  What are you trying to compile?  Are these statistics  for one particular doctor?   I think there is no way to compile statistics.  There are soooo many variables between Doctors, experience, size, medical history and such that  there is just no way to get real accurate data.  As far as less than 10 years of data on radiation treatment, I'm not sure where that came from. Is that for one particular doctor?  I'm sure there is at least 40 years of data.   
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on October 10, 2016, 12:51:24 pm
Sorry, I can't make heads or tails of your post.  What are you trying to compile? 

I'm compiling the chances of losing nerve functions between retrosigmoid and radiation.

Are these statistics  for one particular doctor?   I think there is no way to compile statistics.  There are soooo many variables between Doctors, experience, size, medical history and such that  there is just no way to get real accurate data. 

Facial nerve preservation may be better than average since the study comes from a doctor who is more conservative on leaving tumor behind. But it won't be more than 2% difference. The other stats were not based on any particular doctor.

As far as less than 10 years of data on radiation treatment, I'm not sure where that came from. Is that for one particular doctor?  I'm sure there is at least 40 years of data.

You're right there is 40 yrs of data for gammaknife. I'm just talking about FSR data.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Jet747 on October 11, 2016, 09:57:42 am
Bomberman,

Interesting post, now I'm going to have to do some compiling and set analysis of this data, which I admit is hard to control for all factors.

I had a pretty good size tumor coming in at 6.2cm.  18 months later my hearing is about the same as pre-surgery/radiation.  >95%.

To further complicate your analysis though let's throw in one more alternative treatment scenario...surgery & radiation.

I had debulking RS surgery followed by GK 6 months later.  This might be the best of all treatments (preserving hearing & other) or the worst of all treatments (increasing future probabilities of problems with another surgery)...only time will tell, even then environmental factors probably play a part in outcomes, one small (possibly irrelevant) example is I had 3 good size cysts around my tumor, now did these hurt or help the short term outcome? Long term?

Right now I can only say, so far so good.  I concede, I'm only 18 months removed from the surgery and could very well be facing another surgery or hearing loss in 10 years or less.  If surgery is required I'm ok with it, certainly it is not a walk in the park but its not the end of the world either.

Being a numbers guy, I like your data driven approach.

If your interested, you could check out a couple of the research studies on the main AN web site to see if your specific case qualifies.  I'm currently enrolled in the Mayo study where they are looking at long term quality of living for AN patients.

Anyways, good post and good luck with whatever approach you choose!

Best,
Jet
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on October 11, 2016, 02:05:37 pm
Hi Jet,

To further complicate your analysis though let's throw in one more alternative treatment scenario...surgery & radiation.

Actually this is the scenario with my RS numbers. It takes into account debulking surgery, and then the chance of GK afterwards. If you already have had GK, then I think you are pretty much in the clear. As GK numbers have nearly 0% regrowth rates from what I remember. May I ask who did you have your treatments with?

I had debulking RS surgery followed by GK 6 months later.  This might be the best of all treatments (preserving hearing & other) or the worst of all treatments (increasing future probabilities of problems with another surgery)...only time will tell, even then environmental factors probably play a part in outcomes, one small (possibly irrelevant) example is I had 3 good size cysts around my tumor, now did these hurt or help the short term outcome? Long term?

My numbers were not specific to cysts. Btw, congratulations on your exceptional outcome. 6.2cm and still with hearing! From what I have read, it sounds like you are pretty much in the clear in terms of regrowth, ie. no more treatments.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Jet747 on October 11, 2016, 03:44:14 pm
May I ask who did you have your treatments with?

Dr.  George Bovis out of the Brain & spine center.  Excellent neurosurgeon.  Highly recommend if your near Chicago.

My documented case thus far:

https://www.anausa.org/smf/index.php?topic=21969.0

My numbers were not specific to cysts. Btw, congratulations on your exceptional outcome. 6.2cm and still with hearing! From what I have read, it sounds like you are pretty much in the clear in terms of regrowth, ie. no more treatments.

Let's hope so!  18 month MRI coming in 1 week.

Be well,
Jet
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on October 29, 2016, 04:47:44 am
Bomberman,

I like your use of probabilities. To me, that's the only way to make sense of this mess.

I get the feeling that the first column was retrosigmoid, but morphed into retrosigmoid followed by radiosurgery.

I would have the table as follows:
                                      Retrosigmoid
                                    +radiosurgery    radiosurgery
facial nerve preservation      92.3%             97.3%
hearing preservation            11.6%             55.8%

That gives retrosigmoid + radiotherapy a 2.9 times higher failure rate for facial nerve and twice the failure rate for hearing preservation. You may want to look at trigeminal neuropathy.

The reasoning for the altered figures is as follows:

Retrosigmoid then radiosurgery facial function preservation

http://thejns.org/doi/pdf/10.3171/2011.7.JNS101921, facial nerve preservation is 96.6% not 97%. Not much of a difference, but to me it suggests bias. Other figures go to a decimal point after the integer, but not this one.

Also, n = 151, since of the 383 patients, 151 commenced with microsurgical resection.

ttps://www.ncbi.nlm.nih.gov/pubmed/25065850 n = 151 since only 151 patients were followed postopersative. The preservation of facial function was 142/151 = 94.0%

I’ll add another interesting paper which is http://www.karger.com/Article/Abstract/447520 from 2106, n = 22, which shows facial function preservation in 86.4% of cases.

Given them equal weight, retrosigmopid + radiosurgery has facial function preservation at 92.3%. So, personally, I would have this figure rather than 96.7%

Retrosigmoid then radiosurgery hearing preservation

https://www.ncbi.nlm.nih.gov/pubmed/25065850, n = 129 has hearing preservation at 11.6%
https://www.ncbi.nlm.nih.gov/pubmed/23749017 is not applicable since it’s for retrosigmoid only.

Radiosurgery facial function preservation

https://www.ncbi.nlm.nih.gov/pubmed/26508404 has facial function preservation at 94 to 100%. In the absence of other information , let’s call it 97%.

https://www.ncbi.nlm.nih.gov/pubmed/21353158 has facial and trigeminal nerve preservation >95%. Taking out the trigeminal nerve and considering the > sign, let’s also set this at 97%.

I’ll add two interesting paper which are http://bmjopen.bmj.com/content/3/2/e001345.full.pdf+html which has facial neuropathy at 1% and http://appliedradiationoncology.com/articles/interdisciplinary-management-of-acoustic-neuromas which has facial aspects at 96%

Radiosurgery hearing preservation

https://www.ncbi.nlm.nih.gov/pubmed/25077322 n>4000 patients, for marginal does <13 Gy, has hearing preservation sat 60.5%. Marginal dose is something that under your control.

https://www.anausa.org/component/docman/doc_download/448-2014-patient-survey-report-final?Itemid=357 n>1000 appears to have hearing preservation at 30.5%

https://www.ncbi.nlm.nih.gov/pubmed/19303780 n=5825 has a hearing preservation at 59%

The same two interesting papers http://bmjopen.bmj.com/content/3/2/e001345.full.pdf+html which has hearing preservation at 52% and http://appliedradiationoncology.com/articles/interdisciplinary-management-of-acoustic-neuromas which has hearing preservation at 63% (Table 2) and 70% (Table 3)

Given them equal weight results in a average of 55.8%.

This flips things in favour of radiosurgery only.

Regards.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on November 14, 2016, 09:58:30 pm
Hi ANSydney,

You are correct, I did combine retro + radio in the chance of failed retro in the first column. And in the second column I did radio + retro in the chance of failed radio.

I didn't see 96.6% in the paper. I only see 97% in there so that's why I used it. You are right after I divided the numbers. But even so, not much difference anyway. You are right, n = 151, not 383. Facial function preservation I see at 146 instead of 142 on page 5 of the PDF. Where did you see 142?

n=22 of the 2016 is too small of a statistical sample size for me. I was taught that n=30 is the minimum. What you can do however is add the 22 and combine with the 151 and average weight those two.

The number you have at 11.6 hearing preservation is only for those who had failed surgery. Those who did not have failed surgery have higher preservation rates so you have to weighted average those two numbers.  It should be higher than 11.6.

For your number 55.8, you didn't include the chance that there is tumor regrowth. In this case, hearing preservation is impossible. That should lower your number. This is the same also with your facial nerve preservation number.  Also as time goes on the chances for tumor regrowth from radiation increases, and the larger the AN the chances also increases.


Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: caryawilson on November 14, 2016, 11:15:29 pm
Thanks Bomberman. Great analysis.  When I looked at the statistical data, I always questioned the validity of the data due to the sample size.  I guess I need to spend more time looking at the data, my own personal experience may be skewing my analysis.  In summary:
* Large AN, 4.5 cm
* the location of my tumor was stressing cranial nerves 5-12.  Nerves 7 and 8 were removed and the I have issues with 5, 9, 10, 12. 
* by the time of my surgery I had lost the ability to produce tears in the eye on the side of my AN.  Hence, it was clear my Facial Nerve had significant damage.
* vascularity.  My tumor was highly vascular, and my surgeon made the conscious decision to remove my facial nerve in order to remove more of the tumor.
* location: 

Hence, in my case, the key factors were: size, location, damage to existing nerves, tumor characteristics. 
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 18, 2016, 04:19:38 am
Hi Bomberman,

You mentioned, "Facial function preservation I see at 146 instead of 142 on page 5 of the PDF. Where did you see 142?". I got the 142 from the abstract. I don't have access to the PDF.

You mentioned, "For your number 55.8, you didn't include the chance that there is tumor regrowth." Tumor regrowth is low at about 3%, so even multiplying 55.8 * 0.97 gives 54.1, an essentially unchanged number.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on November 21, 2016, 10:41:14 am
Thanks Bomberman. Great analysis.  When I looked at the statistical data, I always questioned the validity of the data due to the sample size.  I guess I need to spend more time looking at the data, my own personal experience may be skewing my analysis.  In summary:
* Large AN, 4.5 cm
* the location of my tumor was stressing cranial nerves 5-12.  Nerves 7 and 8 were removed and the I have issues with 5, 9, 10, 12. 
* by the time of my surgery I had lost the ability to produce tears in the eye on the side of my AN.  Hence, it was clear my Facial Nerve had significant damage.
* vascularity.  My tumor was highly vascular, and my surgeon made the conscious decision to remove my facial nerve in order to remove more of the tumor.
* location: 

Hence, in my case, the key factors were: size, location, damage to existing nerves, tumor characteristics.

Hi Cary, I'm sorry to hear of your situation. You have already had an op I assume? In that case, these numbers should not apply to you anymore.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on November 21, 2016, 10:42:16 am
Hi Bomberman,

You mentioned, "Facial function preservation I see at 146 instead of 142 on page 5 of the PDF. Where did you see 142?". I got the 142 from the abstract. I don't have access to the PDF.

You mentioned, "For your number 55.8, you didn't include the chance that there is tumor regrowth." Tumor regrowth is low at about 3%, so even multiplying 55.8 * 0.97 gives 54.1, an essentially unchanged number.

https://www.ncbi.nlm.nih.gov/pubmed/25065850 shows that 142 people have facial function after failed surgery and after GK salvage therapy. Non-failed surgeries have higher numbers.

Tumor regrowth is 8% after radio. Not 3% and that is considerable. Especially as the number increases as time goes on and the larger the tumor size. See https://www.ncbi.nlm.nih.gov/pubmed/26508404, supported by https://www.ncbi.nlm.nih.gov/pubmed/22921979, and https://www.ncbi.nlm.nih.gov/pubmed/21353158

I think you really have to read the articles carefully. Taking numbers that suit your preferences isn't going to do you any good.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 21, 2016, 05:07:23 pm
Hi Bomberman,

Good to have a continuing discussion.

Tumor regrowth is 8% after radio. Not 3% and that is considerable. Especially as the number increases as time goes on and the larger the tumor size. See https://www.ncbi.nlm.nih.gov/pubmed/26508404, supported by https://www.ncbi.nlm.nih.gov/pubmed/22921979, and https://www.ncbi.nlm.nih.gov/pubmed/21353158

The mention of tumor regrowth was only to provide a multiplier for the 55.8% figure. I was trying to demonstrate that with the regrowth rates being low, the 55.8% figure did not change by much.

However, let's move onto the topic of regrowth since it is of significance to people with our problem. Here are the three sources you mentioned plus a couple of others and their quotes control rates.

https://www.ncbi.nlm.nih.gov/pubmed/26508404 ........ 92 - 100%
https://www.ncbi.nlm.nih.gov/pubmed/22921979 ........ 90%
https://www.ncbi.nlm.nih.gov/pubmed/21353158 ........ 91 - 100%

https://www.ncbi.nlm.nih.gov/labs/articles/25434946 .......... 97.1%
https://www.ncbi.nlm.nih.gov/pubmed/11483338 ........ >=97%

If we average the ranges and average the 5 papers, we get 95.4%. Happy to have other paper's results incorporated into this conclusion.

I think you really have to read the articles carefully. Taking numbers that suit your preferences isn't going to do you any good.

Acoustic neuroma treatment analysis is an information minefield. If we work together, clarity may be improved. Your enthusiasms for the statistics is just what is needed. However, if you attack the player rather than the ball, we will not get the benefit if navigating the information minefield in a meaningful manner.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on November 22, 2016, 10:45:33 am
https://www.ncbi.nlm.nih.gov/labs/articles/25434946 .......... 97.1%
https://www.ncbi.nlm.nih.gov/pubmed/11483338 ........ >=97%

Hi ANSydney, so you found 2 articles that mention 3% regrowth rates. I think the first link mentions followup of about  5-6 years. But one question is, what is the rate if it's a longer follow up time? Why is there a discrepancy between your 2 articles and the 3 articles I found? Could your articles be only treatment of smaller tumors which are easier to take care of?
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 22, 2016, 07:30:33 pm
There are five articles cited. (Please, if others know of another reference, please add it to the list.)

They are:
https://www.ncbi.nlm.nih.gov/pubmed/26508404 ........ 92 - 100%
https://www.ncbi.nlm.nih.gov/pubmed/22921979 ........ 90%
https://www.ncbi.nlm.nih.gov/pubmed/21353158 ........ 91 - 100%

https://www.ncbi.nlm.nih.gov/labs/articles/25434946 .......... 97.1%
https://www.ncbi.nlm.nih.gov/pubmed/11483338 ........ >=97%

Remember, the first and third have a range. The first article has a radiosurgery control rate of 92 - 100% which, in the absence of any other information, we would use the average, which is 96%. The third article has a control rate of 91 - 100% which, in the absence of any other information, we would use the average, which is 95.5%. (My personal opinion is that if there is a range of 92 - 100%, that the applicable value is closer to 100% than 92% because it is possible to have a control better than 100%, which is shrinkage. This makes the applicable average on higher than the simple average.)

So, the articles are in general agreement with each other (96 +/- 1.5%) except for article 2. It's the odd man out.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 22, 2016, 08:16:55 pm
Bomberman,

I looked at your symptoms and diagnosis date and we are remarkably alike.

You have a 29 mm tumor with slight hearing loss and some face/lip numbness.

I have a 27 mm tumor with slight hearing loss and one side of the tongue has altered taste sensation.

A surgeon's bias is to operate. A radiosurgeon's bias is to radiate. They rarely agree, so they both can't be right for the optimal solution. Yours and my bias is to get the best outcome for ourselves.

You may be interested in reading, if you haven't already, "What intervention is best practice for vestibular schwannomas? A systematic review of controlled studies" at http://bmjopen.bmj.com/content/3/2/e001345.full.pdf [2013]. The conclusion is "The available evidence indicates radiosurgery to be the best practice for solitary vestibular schwannomas up to 30 mm in cisternal diameter". That's us!

There are also some articles that go beyond the 30 mm criteria:

"Gamma Knife radiosurgery for larger-volume vestibular schwannomas"   http://thejns.org/doi/pdf/10.3171/2010.8.JNS10674%40sup.2013.119.issue-suppl [2011]
"Gamma Knife Radiosurgery as Primary Treatment for Large Vestibular Schwannomas: Clinical Results at Long-Term Follow-Up in a Series of 59 Patients" http://www.worldneurosurgery.org/article/S1878-8750(16)30666-0/abstract  [25 mm plus tumor control = 98.3%]
"Long-term tumor control and cranial nerve outcomes following γ knife surgery for larger-volume vestibular schwannomas" https://www.ncbi.nlm.nih.gov/pubmed/22175724 [2011] [25mm plus tumor control = 91%?]

The first article's conclusion is "Although microsurgical resection remains the primary management choice in patients with low comorbidities, most vestibular schwannomas with a maximum diameter less than 4 cm and without significant mass effect can be managed satisfactorily with Gamma Knife radiosurgery"

The second article's conclusion is "Surgical resection remains the primary approach for large VS with symptomatic brainstem compression. GKRS can be considered a safe and effective option in particular in patients who are not good candidates for surgery."

The third article's conclusion is "Single-session radiosurgery is a successful treatment for the majority of patients with larger VSs. Although tumor control rates are lower than those for smaller VSs managed with GKS, the cranial nerve morbidity of GKS is significantly lower than that typically achieved via resection of larger VSs"

I've included these articles since we still fall under the 3 cm criteria, just to let you know there is a buffer. I have another one at home that I can include in the list.

From what I can gather, if you have no symptoms of brainstem compression, which includes both of us, there's some room to move.

You are lucky to be in the US since you can talk to one of the authors directly (Dr Lunsford) and can also talk to Dr Chan who I know has done radiosurgery at 3.2 cm.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 23, 2016, 01:54:58 am
I've done a google search for "gamma knife control rate vestibular schwannoma" for entries over the past year and these were the first 5 papers that came up:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4831944/ ........ 93% control rate after 5 years
https://www.ncbi.nlm.nih.gov/pubmed/26606668 .................. 92% control rate after 10 years (tumor size of ≥4 cm)
http://beating-gbm.org/wp-content/uploads/2016/01/LippitzEvidenceUpdate2015.pdf ........ 97%, 97%, 91.1%, 90.44%, 96.8%, 93%, 79%, 92%
https://www.lgksociety.com/fileadmin/groups/1/Documents/LGKS_2016_-_Slides_PDF/Tuesday/Mathieu_-_Gamma_Knife_radiosurgery_for_Koos_grade_4_VS_BT19.pdf ...... 92% after 10 years (≥ 4 cc)
https://www.scholars.northwestern.edu/en/publications/low-dose-gamma-knife-radiosurgery-for-vestibular-schwannomas-tumo ....... 91% after 5 years.

The last paper shows that it's important to make a distinction between progression free survival based on freedom from persistent growth was 91% at 5 years and progression free survival based on freedom from surgery was 100% at 5 years. Different papers have different criteria for control, with some papers using no growth and some papers consider control to be no further treatment required.

Can we summarize that growth is between 90 to 95% and no need for further treatment is between 95 to 100%. In any case, in the vast majority of cases, control is achieved. Failing that, how about control is somewhere between 90% and 100%.

We need to move on, because the real question is, which is the best treatment option?

Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Blw on November 23, 2016, 06:53:33 pm
With the noted exceptions of size and location, my feeling is that radiosurgery will be vastly more frequent in a few years--I think it is somewhat less now. It has great outcomes, but the ease and cost compared to surgery are significantly better. More importantly, outside of working or not working, there is very little else that goes wrong with radiation. Surgery, in addition to working or not working, can have a huge number of complications that go beyond major surgery (infection, anesthesia, etc), and are specific to schwannomas (leaks, severing nerves, etc). Worse, I can't imagine having a second surgery in the event of a failure, and it also seems to be frequent to leave some tumor behind to preserve the nerve, which almost contradicts the need for surgery.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on November 23, 2016, 08:11:19 pm
Blw, I think you've said it in a nutshell. Nicely worded. I see cranioctomy moving towards debulking, if needed, only. Time will tell. Of course a valid pharmacological solution would change the equation yet again.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on January 18, 2017, 09:33:18 pm
So, I've completed my treatment. I did surgery with Dr. Sisti on 11/18. Everything seemed to be fully recovered 4 weeks out. There was about 1% remaining left. Dr. Sisti was even able to get some that was inside of the IAC which would be extremely helpful with swelling. I am able to still hear in that ear, and this Saturday I am going for a hearing test to see how much of it remained. But I've totally gotten used to it now. I was told that Dr. Sisti was flying blind with the high and low abr bands, but was lucky to still have the mid band to guide him with making sure my hearing was still there. So I think I am really lucky. I don't have to worry about the mass anymore as anything leftover could be zapped if it misbehaved. My numbness and tongue symptoms are totally gone. I also do have a very slight balance issue, but it's so slight, that I can run and move fine. I can do all activities I did before.

I'm glad that the main part of the ordeal is over and done with. And whatever you decide, I hope you will also have a great outcome.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Citiview on January 19, 2017, 05:01:03 pm
Congratulations on a great outcome!
I have read lots of nice things about Dr. Sisti.
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Jet747 on January 20, 2017, 06:14:19 pm
Bomberman,

Great to hear you had such a wonderful outcome!

Keep us posted in the years to come.

Best to you, your family and friends!!!

Jet
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: Bomberman on January 21, 2017, 10:15:23 pm
Here are my hearing results 3 months post op: http://imgur.com/a/7dj4r
About 20% loss. (considered mild hearing loss)
Title: Re: Large AN: radio-short term hearing preservation, surgery-long term tumor control
Post by: ANSydney on January 21, 2017, 11:45:07 pm
A PTA of 26 dB after microsurgery is a great result! The AI of only 62% will probably get better as you work with the altered levels (mine did).