Is Surgery after Radiation more difficult?

[Kate B]

Hi all,

As many of you know, I am a person that looks for trends and relies on data so that persons can make an informed choice.  This report was posted on the other patient listserv.

It was a small study done on patients who chose surgery after GK.  The conclusion suggests that it is more difficult to operate after radiation which makes sense because the treatment "burns" the region. Of the findings, the facial nerve preservation was what caught my eye as all of the patients had lost hearing prior to the surgery.
<The function of the facial nerve deteriorated in 3 patients, was unchanged in 7, and improved in 2.> That means in 75% of the cases, facial nerve function was unchanged or improved..

That being said, if radiation arrests the tumor in 97% of the patients, surgery would never need to be a consideration.
Kindest Regards,
Kate

Microsurgery for vestibular schwannoma after gamma knife radiosurgery.
Shuto T, Inomori S, Matsunaga S, Fujino H.

Department of Neurosurgery, Yokohama Rosai Hospital, Yokohama, Kanagawa, Japan, shuto@yokohamah.rofuku.go.jp.


Background. We evaluated the clinical characteristics of microsurgery for vestibular schwannoma (VS) after failed gamma knife radiosurgery (GKS).

Method. Twelve patients, 5 men and 7 women aged 19 to 70 years (mean 54.5 years), who underwent microsurgery after failed GKS for VS were studied retrospectively.

Findings. The median interval between GKS and microsurgery was 28.8 months (range, 6.6-120 months) and 4 patients had undergone previous microsurgery. The mean volume of tumour at GKS was 6.9 cm(3) (range, 0.5-19.7 cm(3)) and the mean prescription dose to the tumour margin was 12.3 Gy. Microsurgery involved the lateral suboccipital approach in all patients. Tumour expansion involved solid enlargement in 7 patients, cystic enlargement in 3, and central necrosis in 2.Bleeding was slight in all patients except in one, probably because of the pr evious irradiation. Adhesion to the brain stem was severe in 7 patients. Identification of the facial nerve was easy in 5 operations and difficult in 7. Dissection of the tumour from the facial nerve was difficult in most interventions because of severe adhesions or colour change. Severe adhesions between the trigeminal nerve and the tumour was observed in 2 patients. The tumour was subtotally removed except around the internal auditory canal in most patients. Only one residual tumour increased in size and needed second GKS. The function of the facial nerve deteriorated in 3 patients, was unchanged in 7, and improved in 2. All patients had lost hearing on the affected side at the time of microsurgery.

 

Conclusions. Microsurgery for VS after failed GKS presents some technical difficulties. Dissection of the tumour from the facial nerve or brain stem is likely to be difficult. We recommend subtotal resection without dissection of the facial nerve and tumour, because growth of the residual tumour was rare in our series.

 

PMID: 18253695 [PubMed - as supplied by publisher]

[elise]

Kate - Thanks so much for this. It's exactly the kind of information I need right now and am, it seems, unable to find on my own. The statistics are fairly comforting...even citing " improvement" , but basically, I find if whatever it is that I'm facing is broken down to concrete info bytes that I can manage, then I'm in a better place. ( I'm the post GK 6 year looking at what's next person ). re statistics , was it George B Shaw that said " there are lies, damned lies and statistics " ? ..are the statistics for acoustic neuroma still 1 out of 100,000 or have the chances risen with the Rise of the Cellular? BUT statistics, in the right quantity, still work for me somehow.
Elise

[sgerrard]

Why I find this and similar reports not as helpful as they might be:

1. What are they comparing these 12 surgeries to? If they are comparing the results to 12 first-time surgeries, they should say so. It would be better if they compared them to 12 second-time surgeries following 12 failed first surgeries, but at least they should state their comparison basis.

2. 4 of the 12 cases had undergone previous surgery. They make no effort to identify the outcome of those 4, whether there was adhesion to the brain stem in those 4 cases; whether identification of facial nerve was easy, and so on.

3. How do these results compare to surgery of similar sized tumors in general? Each issue they describe, facial nerve entanglement, brain stem adhesion, dissection difficulties, and so on, occurs in some cases of first time surgery. There are posts in this forum describing each of these scenarios. How does 25% facial nerve deterioration compare to first time sub-occipital procedures?

4. The evidence that surgery after radiation sometimes encounters difficulties is undeniable. The important question, though, is whether this potential difficulty is significant enough to be a factor in deciding on initial treatment. That means we need to know
   
A) how does surgery-after-radiation compare to surgery-after-surgery (not how does it compare to first time surgery). Many of the problems encountered would also be encountered if the first treatment had been surgery. First time surgeries also fail, and at about the same rate as radiation.

B) given the likely rate of failure of radiation to control, and the range of results in follow up surgery, how important is this consideration? Using the numbers above, you have 3% chance of radiation failure, and 25% chance of the facial nerve deteriorating in the follow up surgery. That's less than a 1% chance of a facial nerve problem overall. That's still a nice low number.

There is a bit of anti-radiation spin in the presentation of these kind of results. A truly fair report would compare the results to 12 cases where a second surgery was performed after a failed first surgery, to really assess the difference that radiation vs surgery makes in the event of regrowth. The conclusion here, "Microsurgery for VS after failed GKS presents some technical difficulties", is valid, but begs the question "Does microsurgery for VS after failed surgery present some technical difficulties as well?" I would like to see some one address the question more directly.

Steve

[Kate B]

Steve,

Your questions are valid and if I may, I suggest writing the doctors in the publication as the contact email is there.

This abstract would be the shortened version of the entire research report.
My reactions to your questions:
1 and 2.  The scope of this study didn't appear to be a comparison of one form of follow up treatment to the initial treatment for the first time patient or follow up surgery. Those results are out there in different studies.The scope of this study was to report on how these 12 patients fared in surgery after having had GK.  My guess is that the four with surgery previously were those with debulked tumors and then GK.

3. Again, the study wasn't trying to compare how second time responders fare compared to first or second time responders of another treatment.  It was to detail the outcomes for those needing surgery after GK. At one time I did compile the various statistics from many different reports so that I could get at the picture you are trying to get. I used to offer it on this website in 2001 (old format) and as late as 2005 on this website until I felt that it was  getting outdated.   I can dig it out if it would be helpful. It helped me decide on my own treatment.

You ask about comparative statistics. Statistics published about Translab and Middle Fossa are on the HEI website relative to facial nerve outcomes and hearing.  I've copied the Translab results because they usually deal with bigger tumors. http://www.houseearclinic.com/pro_acousticneuroma.htm

Translabyrinthine Approach A recent review from our database of vestibular schwannoma cases provides data from 1302 patients who underwent a translabyrinthine approach between 1982 and 1993. Their mean age was 50.0 years, and 46 per cent were male and 54 per cent were female. Tumor size varied from 0.5 to 6.5cm, with a mean size of 2.4cm. Operating time averaged 3.3 hours. Three (0.2 per cent) deaths occurred in this series.

Data on long-term (6 months) facial nerve function as determined by the House-Brackmann scale were available on 889 cases, with a mean follow-up time of 2.1 years. Of these, 58.2 per cent had a grade I function; 12.6 per cent, grade II; 13.2 per cent, grade III; 7.8 per cent, grade IV; 3.3 per cent, grade V; and 5.1 per cent, grade VI. In this same group of patients undergoing surgery since the advent of facial nerve monitoring (1988), 59% were grade I, 15.4% were grade II, 9.3% were grade III, 7.7% were grade IV, 4.2%, were grade V and 4.5%, grade VI. The vast majority of the poor facial nerve outcomes occurred in larger (greater than 4 cm) tumors. When comparing the risk of facial nerve paralysis in comparable tumors (<3.0 cm), the surgical risks in our hands are only a few percent greater when compared to the most recent gamma knife reports cited above.

 4.  Actually, I thought that these statistics were promising to those needing surgery after radiosurgery. I am an advocate of "One Size Does Not Fit All".To me the larger question is what are the short and long term outcomes related to  treatments and how does that match up with a person's age, location, size etc... (see Guide to the decision making process)?  For example, with surgical patients, hearing levels are typically known in the short term; in radiosurgery, the hearing levels can deteriorate over several years because the radiation effects take longer.   

I actually didn't interpret it as an antiradiation spin...It documented results with 12 (small number) patients. To me, the interpretation is left to the reader. It is what it is....the results are what they are
Kate

[sgerrard]

Actually, I thought that these statistics were promising to those needing surgery after radiosurgery.

Kate, I agree with that, and I think it is useful for Elise, or anyone in a similar situation. I only wish this kind of result was limited to that purpose.

However, it is not. It is often cited not only by patients, but by surgeons and doctors, as a reason not to do radiation in the first place. That interpretation of this result is bad science, bad math, and bad medicine. A 1% chance of facial nerve damage as a result of failed radiation plus complications in follow up surgery is not a good reason to avoid radiation as an initial treatment. If that argument is to be made, it must be based on a fair comparison of apples to apples.

That is why I react to it the way I do. It is not these researchers' fault, or yours, but rather the fault of those doctors who take this kind of result out of its specific context, and use it as a scare tactic with patients who are trusting them to give good advice.

Steve

[Kate B]

Actually, I thought that these statistics were promising to those needing surgery after radiosurgery.

Kate, I agree with that, and I think it is useful for Elise, or anyone in a similar situation. I only wish this kind of result was limited to that purpose....................

That is why I react to it the way I do. It is not these researchers' fault, or yours, but rather the fault of those doctors who take this kind of result out of its specific context, and use it as a scare tactic with patients who are trusting them to give good advice.

Steve

Steve,
As patients the result is our lives...our health... (no matter which treatment and no matter the caring or compassion demonstrated by a physician), for doctors it is really their livelihood( their job).  The medical profession uses information to make their own cases to persuade us that it is the right choice.  Unfortunately, there are surgeons who do that and there are radiosurgeons who use surgery outcomes the same way. Goodness, surgeons have a preference for certain surgical procedures. Recently on youtube, I watched an FSR doctor from NY discuss his procedure to a group in Paris.  The statistics used for surgery were old and outdated. It was the "fear of surgery outcome" factor that was used to persuade people that this treatment was correct. The reason should be his explanation of how the fractionated treatment works and his data. I think you'll agree, the "fear" factor goes both ways.

Yet the researchers and peer reviewed medicine are critical to improvements in the field.  Take GK for example. The have lowered the dosage due to their studies of patients.

The only thing we have as patients is the research to know the outcomes.   Just because I had a positive outcome with middle fossa surgery, it may not generalize to a larger population. That is where the NUMBERS do become important.  They show the result for groups of people using a treatment and with varying attributes (age, size, location)  Just because you had a positive outcome with cyberknife, doesn't mean it can be generalized to the masses. It is the research that shows the results for groups of people and there are generalizations that exist even with the uniqueness of these darn tumors. So while I agree with you that they should not be used as scare tactics. I do believe there is great value in sharing data.

Patients get only one first best chance at treatment.  After that it is trying to correct a side affect (including regrowth)-with either treatment. We do believe our doctors.  There is no doubt that you have to have total trust in your doctor..after all you are placing your future outcome in their hands. 
My attempt continues to be for patients to become an informed patient so that they are fully aware of the "norm" for a typical tumor in a certain location, with a certain size etc... My avenue since 2001 has been to provide patients with a "toolbox of information" including the decison making process guide, the question guide, the AN Chart,the ANWorld website,...

I was a person with AN. I continue to try to Pay if Forward by being an advocate for patients through tools that help them make an informed decision.

I appreciate the intellectual banter.
All the best,
Kate

[ppearl214]

again, all... and as noted... it is all based on personal preference as well as skill of treatment physicians. Please know that radiosurgery techniques (ie: CK and GK) are being redone and have proven sucessful, if necessary, as the failure count is small in numbers (low % of failures that even warrent a re-treat) for both protocols (we tend to hear about them more since the www is readily at our fingers and people note them here more, but please keep in mind the numbers/% across the board for those that don't post here... % are still relatively low of the failures) . An article will be noted in the upcoming ANA newsletter that is going to final print now, as shared with me and JoeF by the ANA.

Yes, surgical removal after a failed radio-process can be tricky..... and I have faith in everyone to work closely with their treatment team to find what works best for their individual situations.

*sits back with popcorn and martini*

Carry on.  I love a lively debate!
Phyl

[sgerrard]

I still want to know the answer to this question:

Is surgical removal after a failed surgery tricky? My contention is that it is, due to formation of scar tissue from the first surgery. In fact, I believe that surgical removal after any failed first treatment is more difficult, because of the trauma from the first treatment.

I cannot understand why the medical community does not address this question in a direct manner. It is absolutely relevant to understanding the meaning of published reports such as the one cited in this thread. Is the result specific to radiation treatment, or is it a general consequence of any first treatment? Only a side-by-side comparison will tell, and no one to my knowledge has been forth coming with that comparison, despite having the opportunity to do so.

Steve

PS: I don't suggest that radiation is the cat's meow of treatment, or the best for everyone, but I do think it deserves to start out with equal footing, and be evaluated for each case with fair and reasonable comparisons. And I also appreciate having a lively discussion...

[leapyrtwins]

Steve -

not to stir up the lively discussion, but can anyone really answer this question?

I'm thinking it falls along the lines of "everyone is different".  Couldn't the medical professionals tell us their opinion(s), but not be 100% sure 
 
Could it be more difficult for some patients, but not for others 

Just a thought,

Jan

[sgerrard]

Oh go ahead, stir up the lively discussion.

I'm sure everyone is different, and a second surgery would be more difficult in some cases than in others.

My point is just that evaluating second surgeries after both radiation and first surgery would give a better picture of whether having radiation or surgery first makes any difference. You would still have to document how often, and how much, the second surgery was more difficult, since it won't be the same in every case.

Fortunately, the regrowth rates are low for both radiation and surgery, so it should not in my opinion be a major factor anyway. Still, I would like to know if there is any difference, but you can't answer that by just documenting one of them.

Steve

[jb]

Just to point out there was a similar study by Drs. Pollock, Lunsford, Kondziolka, et. al., from Mayo Clinic and UPMC that concluded, "No clear relationship was demonstrated between the use of radiosurgery and the subsequent ease or difficulty of delayed microsurgery."  www.jnsonline.org/jns/issues/v89n6/pdf/n0890949.pdf

This issue is also addressed in the "AN Myths" section of the AN Archive website. http://www.anarchive.org/myths.htm
They note, as did Phyl, that the skill and experience of the surgeon is critical with these procedures due to the different texture of the irradiated tumor.

[ppearl214]

Thanks jb for sharing this Mayo article. Interesting, to me, that the study only noted GK patients (understandably so) and the failure rate noted was less than 3% and much of the microsurgical was, for the most part, successful.  Another good reference.... thanks again,

(btw, the popcorn bowl is now empty, if I make more, anyone want any?)


Phyl

[Kate B]

JB,

I have always respected UPMC because they undergo peer review prior to publishing the research.
I find the conclusion interesting in light of the fact that they found 8 of the 13 more difficult, 4 the same, and one actually easier.   Actually this article answers some of Steve's earlier questions too. Later in the article there is reference to scarring.  The surgical cases in themselves have a variety of elements surrounding them.

I guess that second bag of popcorn is needed:-) 

Here is part of the abstract:

Methods. During a 10-year interval, 452 patients with unilateral vestibular schwannomas underwent gamma knife radiosurgery. Thirteen patients (2.9%) underwent delayed microsurgery at a median of 27 months (range 7–72 months) after they had undergone radiosurgery. Six of the 13 patients had undergone one or more microsurgical procedures before they underwent radiosurgery. The indications for surgery were tumor enlargement with stable
symptoms in five patients, tumor enlargement with new or increased symptoms in five patients, and increased symptoms without evidence of tumor growth in three patients. Gross-total resection was achieved in seven patients and near-gross-total resection in four patients. The surgery was described as more difficult than that typically performed for schwannoma in eight patients, no different in four patients, and easier in one patient. At the last follow-up evaluation, three patients had normal or near-normal facial function, three patients had moderate facial dysfunction, and seven had facial palsies. Three patients were incapable of caring for themselves, and one patient died of progression
of a malignant triton tumor.

Conclusions. Failed radiosurgery in cases of vestibular schwannoma was rare. No clear relationship was demonstrated
between the use of radiosurgery and the subsequent ease or difficulty of delayed microsurgery.

[ppearl214]

*starts popping new bag of popcorn*

Kate, to me... the remaining part of the "conclusion" is more of the key....

"Because some patients have temporary enlargement of their tumor after radiosurgery, the need for surgical resection after
radiosurgery should be reviewed with the neurosurgeon who performed the radiosurgery and should be delayed
until sustained tumor growth is confirmed. A subtotal tumor resection should be considered for patients who require
surgical resection of their tumor after vestibular schwannoma radiosurgery."

just my opinion.... no biggie

[sgerrard]

Pass the popcorn, please.

I followed jb's link to the AN Archive, to find these two statements:

"Dr. Chang at Stanford performs both traditional surgery and radiosurgery (Cyberknife) on acoustic neuromas. He said it is false that it is more difficult to perform surgery after radiation."  That's my guy.

"Note that the same issue exists for repeat surgery, since the first surgery usually leaves behind scar tissue with different texture. It is well known that repeat surgeries can be more difficult because of this scar tissue."  This is not attributed to anyone in particular, but it is the point I am making.

Treatment after regrowth is more difficult. Whether you had radiation or surgery the first time. Whether you have radiation or surgery the second time. But not much more difficult in any event.

Plan A) Don't have regrowth.
Plan B) Talk to a surgeon and an oncologist, and treat it again if you have to.

Steve