ANA Discussion Forum
Treatment Options => Radiation / Radiosurgery => Topic started by: rebecca1 on March 03, 2008, 09:52:06 am
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We are considering Proton therapy to treat my husbands AN, size is 1.7x1.2. Has anyone else had this type of treatment?
Thanks,
Rebecca
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Hi rebecca,
I'm not sure which Proton location you may be researching (ie: Loma Linda, MGH, etc). but I know on this site... tsl (Teresa) just had Proton for her AN at MGH mid-last year... I also thought users here of BostAN and/or BostonJake also had Proton here at MGH. You can try a "search" here for Proton Radiation to learn more.
Curious... were you quoted outcomes re: AN and Proton treatment? I had a miserable time, during my treatment decision process, in finding data to support efficacy of Proton therapy for AN's (even locally from MGH). I know many here have inquired and if you have any info to share.... I'll take it.
Also curious if you have researched Gk/CK/Trilogy/FSR and why you boiled decision (at this point) to Proton. Many here that are researching will appreciate your thoughts on it....
Hang in there!
Phyl
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Hi Phyl,
We are considering Proton because it was "highly recommended" by our oncologist as the "ultimate radiation". As far as why use Proton over Gamma or CK, I have no information on its direct treatment of AN. The claim has been made (on net and by several doctors I have spoken with, again doctors in Cancer field) that Proton is stronger radiation, causes virtually no collateral damage, and is non-invasive. I was warned to be careful, that Proton is so strong that if done incorrectly will cause major damage (although I see this as a problem with any of the radiation treatments).
Our thinking is this: If it is stronger radiation, would this not raise the likelihood of "better" destroying the tumor so hopefully it won't come back? It is such cutting edge technology and they use it to treat a lot of brain tumors. I know this does not make it better, and I really believe that who is operating the machine is equally as important as what machine you use.
We are going to MD Anderson in Houston because we had treatment at MD Anderson for my husbands cancer. MD Anderson was the ULTIMATE hospital for Cancer treatment and we HIGHLY trust their team of doctors. When we were told we needed treatment for the AN, MD Anderson was my first thought. I know that in the Cancer field, they are on the cutting edge of so many new treatments. If you have Cancer, there is no place else you would rather be. Plus we know a lot of the doctors. If we go with Proton, this is why we would use Anderson. At this point, I only know that they use Proton to treat AN, but have no information on how many done, outcomes, etc. I will definitely post any information that we gain after visiting MD Anderson.
We have met with a surgeon, a Cyberknife doctor, a local radiologist who was highly recommended to perform Gamma. Anderson's Proton is next week. I don't know what Trilogy and FSR are?
Thanks Phyl for all your time and info.
Rebecca
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Hi Rebecca... makes for a terrific decision-making process... :) I'm glad to hear you are crossing "T's" and dotting "I's". Personally, I haven't heard of it being the "ultimate" radiation as I didn't think there were such a thing... to me, I think it depends on the individual situation and diagnosis as to which form of radiation would work... oh, well.....
I found a terrific link, here on this site... tsl (Teresa, who I previously noted) did a post on the Cyberknife Patient Support board, where drs volunteer there time to answer questions as unbiasedly (is that a word?) as possible.
My dear buddy Mark did a post here to share the dr's response re: Proton and note a study that was done at MGH....
http://anausa.org/forum/index.php?topic=3468.0
In Mark's post, click on the link and it will bring you to the exact post on the CK Patient support board (http://www.cyberknifesupport.org/forum/) with Dr. Medbery's response (lengthy but worth reading).
For Trilogy, "Craig" (a user here) had it done and he's doing well from what I hear. Try doing a "search" for Trilogy and you can see Craig's story. For FSR (Fractionated Sterotactic Radiation), oh, there are many many here that have had it done to treat their AN's. Also try a search for FSR for further info.
So, to Mark and tsl/Teresa (see you at the brunch, hun!), I say thank you for starting this leg work... I hope this info is helpful.
Phyl
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Thanks for the link. This is the kind of information we really need to help make the decision. I want to take it to Anderson see what they have to say about it. I certainly don't want any of those side effects. The only symptom my husband has is ringing in ear. I cannot imagine coming out of treatment with no hearing, facial paralysis, etc. I read some posts who seem to do OK with it, and some who did not. Probably like everything else. I really like the studies referenced by Dr. Medbery though, facts and statistics can be a good thing. All the articles we have read, it really seems like the chief advantage to Proton is less collateral damage. Stronger radiation, more targeted hit, and less damage than conventional radiation. Put Proton in search engine and you get this over and over. Are GK and CK considered conventional radiation? Am I reading it right? Yet Medbery's statistics seem to show more problems with Proton than GK or CK.
Making the decision - the toughest part?? Thank god for sites like this one that help sort through the info.
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rebecca,
Since Phyl is tossing my name around, let me offer my two cents on what I have seen written on Protons.
There is no such thing as the "ultimate radiation" , I would classify that as marketing hype. All radiation works the same on the tumor whether it's source is cobalt ( GK) , linear accelerator ( CK and others) or proton. Collateral damage is a function of the delivery accuracy of the machine, not the type of radiation. In that regard, CK , to my knowledge is still the best based on clinical studies (.89mm) with GK slightly higher at 1.2-1.5 mm. The alleged advantage of Protons is that they hit the tumor and stop whereas X-rays pass through. However, the amount of dosage in the X-rays is designed to be so low in individual beams which do not cross as to minimize impact on healthy tissue. Proton machines are hugely expensive , usually 4-5 times a CK unit ( $20-25M vs $5-7M) but have to date not shown any enhanced efficacy in terms of outcomes compared to the other machines, yet as the Post from Dr. Medbery showed in clinical studies it does seem to have a higher level of complication. I will offer another post from Dr. Medbery on his view of Proton and I find the closing comment to be quite illuminating so I'll highlight it.
PRotons have not been shown to be superior for any tumor. They are probably as good for certain things such as clivus chordomas etc, but they have not been shown to be superior or even as good as CK or GK for AN. In fact, MGH reported ontheir series in 2003:
RESULTS: The actuarial 2- and 5-year tumor control rates were 95.3% (95% confidence interval [CI], 90.9-99.9%) and 93.6% (95% CI, 88.3-99.3%). Salvage radiosurgery was performed in one patient 32.5 months after treatment, and a craniotomy was required 19.1 months after treatment in another patient with hemorrhage in the vicinity of a stable tumor. Three patients (3.4%) underwent shunting for hydrocephalus, and a subsequent partial resection was performed in one of these patients. The actuarial 5-year cumulative radiological reduction rate was 94.7% (95% CI, 81.2-98.3%). Of the 21 patients (24%) with functional hearing (GR Grade 1 or 2), 7 (33.3%) retained serviceable hearing ability (GR Grade 2). Actuarial 5-year normal facial and trigeminal nerve function preservation rates were 91.1% (95% CI, 85-97.6%) and 89.4% (95% CI, 82-96.7%).
If I were getting that kind of toxicity with CK I'd slit my wrists.
--------------------------------------------------------------------------------
Clinton A. Medbery, III, M.D.
St. Anthony Hospital Cyberknife Center
(405) 272-7311
buddy@swrads.org
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Mark - Great info. Thanks.
But I don't get it. Anderson's proton center cost $126 million dollars. Why spend that kind of money if there is no greater benefit (not to mention more complications) than other types of radiation? The treatment of the tomorrow? I really don't want to be the guinea pig.
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First: Hi Mark, nice to see you back. 8)
Next: Hi, Rebecca, I don't know a great deal about Proton, though I have heard of it. But I think it is important to separate Proton in general, for a wide variety of tumors, and Proton specifically for AN. My impression is that it has not been used extensively for AN, and that the results when it has been used were not as good as expected. That doesn't mean it is not a very useful system for treating many kinds of tumors; only that it may not be the best choice for ANs. The location of the AN next to cranial nerves, the type of tumor, and the fact that they are slow growing and benign, puts ANs in a different category from other tumors. ANs don't need strong radiation, just very precise delivery.
My view: GK is all in one day - a little too much at once. Proton, Trilogy, and FSR, many small doses over several weeks - too many repetitions, more chances for stray radiation, not quite enough at once. CK is just right - 3 to 5 precise zaps.
It sounds like you are doing lots of homework, and gathering lots of information, keep up the good work.
Steve
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Rebecca,
Hard question to answer, the $126 million sounds like the total cost of a separate center, bricks and mortar, etc , plus the machine. At any rate, having been in the medical supply business for 25 years I can safely say that not all hospital decisions are made from a logical cost/benefit business perspective. Poor due diligence, doctor ego , especially one who is a big revenue generator, or wanting to maintain a industry leader/ cutting edge image all tend to factor into these things. MD Anderson is clearly one of the great cancer treatment centers in the world and financially well endowed I suspect so I wouldn't be surprised if some of the mentioned non financial motivators come into play. Also as Steve and Dr. Medbery both noted, perhaps Protons might demonstrate some enhanced efficacy on some specific cancers or tumors, but the studies to date clearly show a higher complications and less tumor control rates than "conventional" radiation delivery machines for AN's. Other factor is that an AN is treated in proximity to cranial nerves and perhaps Protons don't react as well there as in other parts of the body. or perhaps they haven't refined the dose or delivery protocols yet. Who knows at this point and with so few centers ( Loma Linda and MGH come to mind) investing in protons there is a certain "guinea pig" element involved.
mark
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Hi Steve,
Thanks for the welcome back. Phyl finally agreed to raise my fee/post rate ;D :o
Seriously, I've had a lot of work and travel related time constraints the past few months as well as an another issue that affected my ability to participate, but I promised Phyl I would try to drop in occassionally to offer my thoughts as time permits.
;)
Mark
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cheeky! ;)
good to see you posting again, Mark... and as for the fee raise..... um, I have a dr's note for short term memory... I don't remember THAT conversation! :D
xo
P
Hi Steve,
Thanks for the welcome back. Phyl finally agreed to raise my fee/post rate ;D :o
Seriously, I've had a lot of work and travel related time constraints the past few months as well as an another issue that affected my ability to participate, but I promised Phyl I would try to drop in occassionally to offer my thoughts as time permits.
;)
Mark
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Yes, how naive of me..... I forgot all about that little thing called ego, my proton machine cost more than your CK machine, etc. It was mentioned to me that Proton may have a possible side effect of unknown element as it is unclear what happens when the nuetrons produced by the Protons circulate the body. Theoretically, this could cause problems down the road, but it is unclear in field if this is the case. I have not reasearched this myself, just passing along info, take it for what it is.
On another note, we just met with a rad/onc who does FSR (linear accelerator). 28 treatments, 2 min each, no screws, sounds pretty good. What are major differences between CK and FSR? From researching this site, I get the impression Linear is less accurate than GK or CK. Correct? Is there an advantage to using the fractionated treatment over 28 days vs something like CK in 3 days? Is the theory that each 28 day treatment produces less radiation therefore less likely to damage adjacent nerves and preserve hearing?
It just seems like each doctor visit just raises more questions......
Advice is GREATLY appreciated.
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Rebecca,
People on this board have had good results with all the machines, so take the following comments in the context of probabilities based on clinical studies I've seen and conversations or reading posts from various neurosurgeons / radiation oncologists over the years.
In general FSR (25-30 session) machines are not as accurate as CK or GK , hence the radiotherapy classification as opposed to radiosurgery. This tends to be the driver as to why doses are between 1-2 GY so as to minimize collateral damage to healthy tissue. Down side is total radiation dose usually is in the 50 GY range as opposed to 12GY for 1 dose GK/CK or 18GY for 3 fractions CK. other issue is the ability to replicate positioning obviously has more risk at 30 sessions than 3
Tumor control and hearing preservation rates with FSR, overall are at best equal and generally slightly worse than GK / CK results.
GK requires the frame and is limited to one dose, CK has the has the ability to do fractions which may give slightly better hearing preservation % and matches the GK level of accuracy without requiring the frame, the latter being a personal comfort issue for some people.
again, folks have good outcomes with all the machines, but those would be some points of difference that I see.
Mark
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rebecca,
one other point of clarification. all machines other than GK use a linear accelerator to generate the radiation, GK uses Cobalt. There is no difference biologically on the tumor from either source.
Mark
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Mark -
So CK is a linear accelerator, same radiation, just delivery method is different than FRS treatments? CK is more accurate so can give higher doses of radiation and only need 3 treatments?
Forgive me if I sound ignorant, but why would 50 GY range be a downside? And why do they do so many treatments of FSR - why not stop at say 10 or 15 treatments to make total radiation similiar to GK or 3 fractions of CK?
If it takes 50 GY to work for FSR, why does it only need 18 GY to work with CK?
Thanks,
Rebecca
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Rebecca,
Yes, CK uses a linear accelerator to create it's radiation beam which is the same as the FSR machines.
The answer to the rest of your questions really goes beyond my knowledge technically and could be better explained by either the radiation oncologist or physcist on the planning team. part of the the extended number of treatments is compensating for the inability to hit the target as precisely as CK or GK and part is simply the protocol preference of the physcian using the machine. The major difference with CK over the other machines and what gives it the accuracy advantage is that it actively targets the AN during treatment where other systems are totally dependent on the CT scan programing and can not adjust for inadvertent movement or misplacement of the head on the table. The superior accuracy of the radiosurgery machines allows for a higher dose with less risk, so the analogy is that one dose of GK / CK is hitting it with a sledgehammer, 3 fractions with CK is using a mallet and FSR is like using a tinsmith's ballpin hammer. It takes a whole lot of little hits to get the required "kill effect". It's not clear that there is any negative to receiving a total dose of 50Gy over 12 or 18, but my personal view is that less is better. You might post your question over on the CK board for the docs there to respond, but from a layperson's perspective I think my analogy is pretty close.
Mark
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Mark,
Great information and analogy. I really appreciate your time.
Thanks.
Rebecca
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On the 1 dose of 12 Gy = 3 doses of 6 Gy = 25 doses of 2 Gy, which also puzzled me, I can report two responses:
Dr. Chang said in an email to me "We would use a dose of 18 Gy total delivered over three 6 Gy treatments, this has the same biologic effect on the tumor as 12 Gy
delivered in a single shot, which is typically what the gamma knife centers use."
Dr. Medbery on the CK forum, when asked why, said more or less "that's just the way it is." Not much of an explanation, but perhaps in the end more useful than some messy integral calculus formula for biological equivalence.
Somehow, the less per shot, the more total radiation you need to get the desired biological effect.
Steve
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I thought I would put my two cents in. Just to recap, I had my treatments done with the Trilogy machine in April of 2007. I had 4 treatments of 6GY. I am doing fine and I am training for the Country Music Half Marathon on April 26th. I have my one year MRI scheduled for the 21st so I will post an update then. The only two symptoms that I have now are an occasional wobbliness and short term memory issues. The memory issues should clear up in the next year or so.
If you are still deciding on what maching will zap your head, it really boils down to the comfort level that you have with your doctor. You have to remember that each doctor is selling himself and his machine so they are going to tell you that their machine is the best. Do your research and make the decision that makes you feel comfortable. The decision is the hardest part.
Good luck to you,
Craig
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SURE appreciate all the information on this thread. I couldn't find it the other day when I was looking for PROTON info / patients.
This thread is FILLED with so much information. Can someone help decipher it for me? (I feel like I need to read it with a spread sheet!)
What I want, Treatment wise, the most important thing is the LOWEST DOSE per day of radiation...per zap/whatever. I do not care about the cage, the mask, the environment, etc. Because those things are temporary; I can mental-image my way through any of that! I do not care HOW LONG the treatment takes. If it takes a week, or a month...that is life, it is temporary.
The second item I look for is Effectiveness of the treatment....best track record.
The third thing I look for is Salvation of the Hearing! This is because my hearing is fine.
The fourth thing I am looking for is no facial problems caused by the treatment. Why should the medical community cause prob?
The last thing I am looking for is no post treatment migraines. I have them; why have more?
I rate things like that because I can Live THROUGH ANY treatment; they are just temporary, the after-effects are! I do not want to live Without an effective treatment.
I do not want to live for-forever without my hearing...or some messed up facial muscles and eye lid muscles.
And, I already treat migraines...So, I hope the treatment does not INCREASE them.
IMO: The reason that the lower the per dose of radiation needs more total radiation is ...to my 'mechanical' mind easy to look at. I am NOT a nurse...I used to dp maintenance at factories then I taught maintenance men! And, it makes sense that the radiation would seep into the cells, so would ACCEPT a larger TOTAL dose than a larger dose done over a shorter period of time. IMO, it is SIMILAR to injecting some oil into a sponge; some would go in....you wait for it to absorb; you inject more....you wait again. If you inject a bunch at once, the sponge can not hold as much. It might not be a medical explanation...but...that is where my head goes...! ha-ha Like I said...just IMO
Can anyone help me figure out the 'alphabet soup' of the non-surgical procedures? Likd I said I am NOT a medical person, I am so confused over the different treatments!! Can someone simplify things? Does anyone have a 'table' evaluating the different procedures? Statistically, with weights for the different items...
The people /Drs you say to discuss it with...I do NOT think we even HAVE them here in this AREA! I live in a REMOTE Area! When I called Loma Linda for information, I tried to explain to them that when I go to the specialist, I drive 4 hrs at 75mph; no stops! Just to Get there!! It is Interstate all the way...Mtn pass/Desert, tumbleweeds, sagebrush, no cell phone towers, wide open spaces, blue sky! My house is less than a mile from the on-ramp to the interstate...and we FLY down the road!! They have doctors here for simple things like having Open Heart Surgery...there are a lot of Old people here! ha-ha! But, the specialists are not here for AN's. If I go a diffent direction, it would be about 7 hrs! The other 2 directions...ummm!! unknown!
So, if you all can give me some advice, as far as MOSTLY, which TYPE...
and ALSO where...what locations...I prefer SO CA; or Albuquerque; or several other places....but not the New England area. If anyone knows anyone in those areas...I would have someone to play nursemaid to me -ha-ha. I can fly/drive to a location to have the procedure done. It would be nice to have a support system there!
Thanks!!
Idaho
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Idaho...I think it is important to know that no matter what treatment you choose, no treatment can be guaranteed 100% to be without risk. Doctors can recite each of their statistics, but no two tumors are alike. Two people with the same size tumor can have very different outcomes with the same treatment at the same facility(depending on tumor location, condition of their facial nerve, etc.)
Every treatment has risks as well as benefits. It is very important to interview all of your health care providers and understand what those risks and benefits entail. Making a decision about treatment (what to do or not to do) can sometimes be the hardest part. Good luck in your quest.
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Craig said:
If you are still deciding on what maching will zap your head, it really boils down to the comfort level that you have with your doctor. You have to remember that each doctor is selling himself and his machine so they are going to tell you that their machine is the best. Do your research and make the decision that makes you feel comfortable. The decision is the hardest part.
That really isn't TOTALLY accurate if the doctors one CAN talk to are not Selling Their machines. I am talking to doctors here in Idaho; they are telling me about machines located in Loma Linda (Proton Therapy) and Los Angeles (House Clinic). So, they certainly do NOT have a Vested interest. OF COURSE, I am asking questions of them regarding CK and GK; and they do not recommend them OVER Proton therapy! The surgeon I talked to who was at HOUSE said if your hearing is 'THAT GOOD, don't DO surgery NOW!' My reply was YIPPIE! ::)
The surgeons in Salt Lake want to to a Translab procedure; which would 'kill' my hearing. Since it is Fine now; my question is WHY? And, it will cause Problems! Not just the week in a hospital 4 hrs from home and a few weeks recovery time. I have been told to expect additional surgeries to correct the problems that the surgery will Cause! I say SO, why BOTHER? ::) They say, DO NOT put it off any longer!!
Diff Drs have Diff opinions!! Isn't that the way life is? RESEARCH -- research - research!! Then, simply pray you made the right decision.
And, you evidently don't know for sure for years. The one young lady, in Texas, with 3 bouncing blonde daughters, (I don't remember her pen name) had surgery 12 yrs ago, and is now going through painful corrective surgeries! And, she NOW is the age of my Youngest daughter! So, I guess I have age on my side...I probably won't LAST THAT long! :D Except that I have long living genes! But, they MIGHT improve procedures in the mean-time! Right? That is why I am AIMING at the Proton Therapy. So, that IF my AN / facial Schwannoma GROWS after the Proton Therapy, MAYBE--just maybe medical science will have improved in 5 or 10 years and they will be able to surgically remove it without killing the hearing.
OR is anyone even DOING any research on that option? Since patients aren't complaining/dying/suing about the situation....the medical community does not change things! And, when they do, it is SLOW.
Thanks for any information. But, PLEASE when you write results, please write them in layman's terms..Not Medical-ease! Some of these discussions are CHALLENGING to understand (and I graduated from college with a 3.7gpa, so I CAN READ!)
Thx...Idaho
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Hey Idaho! Great to see you posting! :)
I'm not going to put words in Craig's mouth... but in line with what both of you are saying..... we know dr's will share with us what they have knowledge of options. If a doc is familiar with one procedure or another, then, that is what they will share with us as patients. You both are correct that you have to find a team that you are comfortable... and with experience. We do know of some docs that swear by what they know... but, yet again, they sell "comfort points". Talk about what they know... stay clear of what they don't. Heck, my brain surgeon (who cuts for a living) did her internship in GammaKnife... never heard of Cyberknife... and she let me educate her on it! :)
Craig, if I'm outta line, just let me know.. and btw, I sure do hope you are feeling well! You know I'm following your progress. :)
Idaho, many times in patient situations, as much as we are not inclined to understand what docs (or others) tell us as the info may be above our heads. I agree with you about better understanding in laymen's terms. Many will share that in order to choose what is best for your situation, then we really do need to understand a bit more that just the laymen's terms. In that regard, I agree... since it's our head/skull they are working on, then you bet I'm going to learn all I can about it. Just my opinion.
In asking about Proton... if you do an online search (whether on this site or elsewhere), the info is limited on the success of Proton for the treatments of AN's. I pointed someone to you (tsl/Theresa) who recently had proton done here in Boston at Mass General Hosp. She's a terrific reference to discuss Proton. Another option is the CK Patient Support Board (http://www.cyberknifesupport.org/forum/) as the docs that volunteer their time to answer patient questions on that site are very well versed in all forms of radio-treatments for AN (not just CK... but GK, Proton, FSR, etc).
As I've shared with you, it really is up to each individual to do the best research we can and to become the best, well-informed patient we can be. You are doing everything right... esp. here by asking questions. As you can see, the responses to your Proton questions are limited as not many here have had proton for AN treatments. Now, there is scientific info available re: "total" accuracy of all forms of radio-treatments on AN's, how the procedures are done, etc. In my opinion, in as much as we don't like things beyond "laymen's terms", sometimes we have to go that route to help investigate what is going to be best for us.
You will know what is best for you... you know how to find me and all of us here can point you in the right direction.... You know I'm cheering you on and hoping folks here help provide you answers that you seek. :)
Hang in there!
Phyl
(btw, the woman you reference with the 3 blonde girlies is Kaybo. She posted pics of herself on her blog and her recent facial surgery is coming along nicely. She's getting her smile back and forging forward. She really is a true inspiration!)
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Phyl...
I've done follow-up on the references you've given me. They have been helpful....I appreciate them...and all the work you do.
Glad to hear the young lady in TX is doing well....I HURT just Reading her blog!
I'm awaiating an answer from one of the Docs on the Cyberknife board.
Has ANYONE had treatment at the Pomona Valley Hospital at POMONA, CA? I checked with them for FSR; which they DO. But I could not get info without GOING there! That's not reasonable; should be able to FAX records and have them reviewed! Just like one can do at House Clinic and Loma Linda Hosp. :(
Thx & cheers...Idaho
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Hey Idaho,
Oh, I don't hurt when I read Kaybo's blog.... I smile and smile... she's got amazing mental strength and nothing by admiration from me for all she has endured. I absolutely commend her... plus, she told me that if I ever get to TX, I have free room and board! :) I may have to take her up on that.
I can share that the docs on the CK Board (Dr. Medbery and Dr. Spunberg) will also read your films if you put them in the mail for them. Dr. Medbery reviewed my films in the past and I know of some that sent to Dr. Spunberg. If you send to them (Dr. Medbery is in OKC, Dr. Spunberg in FL), they will give you professional advise as well... even if they think surgery should be done vs. radio or vice/versa. They will answer your questions as well. A good starting point and hope they respond to your questions soon.
Phyl :)
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rebecca,
Since Phyl is tossing my name around, let me offer my two cents on what I have seen written on Protons.
There is no such thing as the "ultimate radiation" , I would classify that as marketing hype. All radiation works the same on the tumor whether it's source is cobalt ( GK) , linear accelerator ( CK and others) or proton. Collateral damage is a function of the delivery accuracy of the machine, not the type of radiation. In that regard, CK , to my knowledge is still the best based on clinical studies (.89mm) with GK slightly higher at 1.2-1.5 mm. The alleged advantage of Protons is that they hit the tumor and stop whereas X-rays pass through. However, the amount of dosage in the X-rays is designed to be so low in individual beams which do not cross as to minimize impact on healthy tissue. Proton machines are hugely expensive , usually 4-5 times a CK unit ( $20-25M vs $5-7M) but have to date not shown any enhanced efficacy in terms of outcomes compared to the other machines, yet as the Post from Dr. Medbery showed in clinical studies it does seem to have a higher level of complication. I will offer another post from Dr. Medbery on his view of Proton and I find the closing comment to be quite illuminating so I'll highlight it.
PRotons have not been shown to be superior for any tumor. They are probably as good for certain things such as clivus chordomas etc, but they have not been shown to be superior or even as good as CK or GK for AN. In fact, MGH reported ontheir series in 2003:
RESULTS: The actuarial 2- and 5-year tumor control rates were 95.3% (95% confidence interval [CI], 90.9-99.9%) and 93.6% (95% CI, 88.3-99.3%). Salvage radiosurgery was performed in one patient 32.5 months after treatment, and a craniotomy was required 19.1 months after treatment in another patient with hemorrhage in the vicinity of a stable tumor. Three patients (3.4%) underwent shunting for hydrocephalus, and a subsequent partial resection was performed in one of these patients. The actuarial 5-year cumulative radiological reduction rate was 94.7% (95% CI, 81.2-98.3%). Of the 21 patients (24%) with functional hearing (GR Grade 1 or 2), 7 (33.3%) retained serviceable hearing ability (GR Grade 2). Actuarial 5-year normal facial and trigeminal nerve function preservation rates were 91.1% (95% CI, 85-97.6%) and 89.4% (95% CI, 82-96.7%).
If I were getting that kind of toxicity with CK I'd slit my wrists.
--------------------------------------------------------------------------------
Clinton A. Medbery, III, M.D.
St. Anthony Hospital Cyberknife Center
(405) 272-7311
buddy@swrads.org
Wow....you have no idea how upset this makes me. They knew at the time that they were selling me on the proton beam that it had higher levels of toxic effects than other delivery methods!
I feel like I may have gone through more pain and suffering than was necessary just so that MGH could pay for their shiny new proton beam center! And to top it off my AN is growing again!