Novalis shaped-beam radiosurgery

[crystallady]

I just want to share that there is another type of radiosurgery that is used in Rochester NY at the University of Rochester Strong Memorial Hospital.  The Novalis shaped-beam technology, developed over the past 15 years by BrainLAB Inc. of Munich, Germany, conforms the radiation beams to match the size and dimension of a tumor and then kills those cells, leaving surrounding tissue unharmed. It also accommodates the slight movements of internal organs during normal breathing and blood flow, monitoring the rate and scope of movement and shutting off if movement varies, sparing healthy tissue.

I am doing research into this type of radio surgery for my AN/meningioma on my right ear and ping pong ball size meningioma on the top of my head.  Its very impressive. 

Thought I would share this with everyone.

[Mark]

 To offer some other thoughts on Brainlab,

Novallis by Brainlab is an IMRT technology that has the advantage of treating both cranial and extra cranial tumors more effectively than conventional radiation therapy machines. However it's level of accuracy is significantly less than GK or CK, especially when Fractionated treatments are proposed. It will typically involve 20-30 short treatments to compensate for the inaccuracy as opposed to machines that do radiosurgery. For a cranial tumor where accuracy is imperative, GK or CK would be preferable choices in my opinion. For tumors elsewhere in the body Novallis would be a significantly a better option that conventional but would still not be as precise as CK is able. a review of some of the pros and cons and overview is a s follows

Shaped Beam Systems
The recent development of IMRT or Intensity Modulated Radiation Therapy has added another dimension to multi-fraction radiation therapy. These linac-based technologies use computer-controlled "beam-shaping" to do a better job of conforming the radiation dose to the shape of the tumor or other lesion. This form of advanced radiation therapy can be utilized at virtually any location in the body. IMRT technology enables a mechanical device (called a multi-leaf collimator) that is typically attached to most modern medical linear accelerators, to dynamically reshape the outlines and intensity of the radiation field during cancer treatment. When combined with sophisticated planning software, IMRT fits the dose of radiation to a target much better than conventional radiation therapy, and thereby minimizes the volume of surrounding normal tissue that is injured by treatment. While it appears that IMRT may produce fewer side-effects than conventional radiation therapy, IMRT is not as spatially precise as radiosurgery. Because of this imprecision, a full course of IMRT treatment is typically administered over multiple treatment sessions (typically 20-30+). Common brand names include X-Knife (Radionics) and Novalis (Brain Lab). Advantages of Shaped-Beam systems include:

   1. The capacity to treat most regions of the body with IMRT
   2. When coupled to an invasive stereotactic frame, precision targeting for brain tumors that approaches, but does not equal, that of the Gamma Knife or CyberKnife.
   3. The capacity to more accurately target extracranial (non-brain) tumors than standard radiation therapy
   4. An ability to deliver fractionated intracranial or extracranial treatment

Disadvantages of the Shaped Beam systems include:

   1. The need for an invasive head frame (similar to the Gamma Knife) to assure treatment accuracy when used for brain radiosurgery (single fraction)
   2. Less treatment accuracy when multiple fractions are used to treat areas of the brain where the use of an invasive head frame is impractical
   3. A significantly lesser degree of targeting accuracy when treating extracranial tumors compared to brain radiosurgery
   4. Treatment accuracy is degraded further when the target moves during radiation delivery from either natural breathing or patient movement


Mark

[crystallady]

According to the doctors here, i would only need one treatment for the one in my ear because of the precision of this machine. They have not talked about 20-30 treatments at all.  This type of treatment has irradicated tumors quicker and no regrowth.  My research continues but I am not convinced that the Gamma Knife is better.

[Mark]

crystallady,

I believe what your doctors are proposing is the one shot dose approach where a head frame similar to GK is used which was outlined in advantage #2

When coupled to an invasive stereotactic frame, precision targeting for brain tumors that approaches, but does not equal, that of the Gamma Knife or CyberKnife.

In that scenario Novallis still will be slightly less accurate than the other two machines. The differences in accuracy between the various machines has been demonstrated in clinical studies so there is not much dispute with that fact. Ultimately, the patient has to decide whether the variance concerns them

The 20-30 treatments comes into play when the machine is used for fractionated treatments and again the reduced accuracy of the machine coupled with being unable to wear a frame for that many days requires smaller doses than a CK which would do it typically in 3-5 days.

In many ways the patients choice of treatment ( single dose vs. FSR) should dictate which machine is the best option based on it's capability. There is preliminary but growing evidence that FSR provides comparable tumor control with better nerve preservation % than 1 dose treatments.

 Novallis is certainly a very capable and adequate machine for treating an AN and many people have used it. However in dealing with cranial tumors my research would lead me to believe either GK or CK would still be better choices. Novallis primary advantage has been it's improved ability to treat below the neck tumors more accurately than conventional radiation machines over the past years. However, CK which is a newer technology which appears to be surpassing it in that arena as well.

Just my 2 cents

Good Luck

Mark

[jerseygirl]

My neurologist who has followed my AN for years recommended Novalis over GK should I decide to go the radiation route. He said it is a newer, much more precise technology that delivers radiation more evenly to the tumor than GK ( I have an irregularly shaped tumor since it is a regrowth). He went on to talk more about it but I do not remember all of it. He believed it will be the future in the radiotherapy. When I expressed a concern over a number of treatments, he said I should discuss it with the doctor who does it because in many instances it can be done in one shot. The two people he sent had their treatments done in one session. In NYC Mount Sinai Hospital has Novalis. Since I decided not to go the radiation route, I never followed up. Hope it helps.

 Ã‚ Eve

[Dani]

Mark,

Hi.....I have been back and forth in trying to decide GK vs. CK.  Could you or someone else that has had the CK tell me why you chose that one over the GK.  It does sound like a lot better route to go.  How many treatments does it take for the CK?  Also does anyone know of anywhere that does CK in the Northwest?

Thanks,
Dani

[Mark]

Dani,

In general, the primary reasons for picking CK over GK would be

1) avoiding the need for the invasive headframe
2) GK can not do FSR, CK can, usually in 3 treatments but I have seen a couple at 5, depends on the treating center protocol

There are a couple of GK centers that will attempt to do Fractions, but it is not very common and I think that while some folks don't feel the headframe is overly painful for one treatment, I can't imagine doing it over a few days.

In short, if you choose one shot dose, either works and the decision point is the frame. If you choose a FSR approach then GK is not an option and CK is by far the most accurate machine over multiple days

I believe there is a new CK site in Seattle, but www.accuray.com would have the most up to date list

Additionally, Eve raised a good point on the machines ability to treat irregular shaped tumors (isometric) with even doses as opposed to creating "hot and cold spots". I believe that GK has the potential for 208 beams but even that flexibility provides some limitations. Novallis is also treating based on the assumed position of the tumor from a CT scan like GK, but my understanding is the shaped beam capability allows it to avoid the hot / cold spot issue pretty well. CK is also highly effective on even dosing irregular shaped AN's because it is actively targeting the tumor during treatment and the robotic arm allows greater beam flexibility than fixed machines.

Hope that helps

Mark

[Derek]

Hi Mark...

Your posts on this thread are patently impeccably researched, extremely helpful to those who are in a dilema as to which treatment to consider and are very well presented.

Thanks.

Derek

[Mark]

Bruce,

here is the Stanford study which primarily benchmarked CK against GK since the latter has always been regarded as the "gold standard" for accuracy over the years.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12493111&dopt=Abstract&itool=iconabstr

There is also a very good discussion about accuracy by Dr. Chang which I posted in the radiosurgery section of the archives here which goes through the concept of Total accuracy of dose to the tumor. For example, all machines begin with an inherent error related to the CT scan and then you layer in frame error ( if one is used) and then other factors related to the specific machine. In this context GK and CK both generally are reported at around 1 mm . I still need to figure out where I saw the Novallis comparison but I believe it was closer to 2 mm.

I did "cheat" and post the question to the docs over on the CPSG board who have used all of them and I'll post their response when I get it.

Again, to emphasize my initial point. Novallis is a very capable machine for treating an AN effectively when a frame is used and I would never suggest it isn't. However, I would also not say it's the newest technology or superior to GK or CK for AN's. many hospitals select it I believe for it's versatility. It is better than conventional machines for body tumors and can also handle cranial lesions nearly as good as GK. GK can only do cranial tumors, so if you can only afford one machine at your hospital then Novallis was an excellent option until CK came along.

Mark

[Mark]

Thanks Derek,

I very much appreciate the feedback, glad the information is helpful

Mark

[crystallady]

 Funny how how my doctors who have used this procedure for 15 years dont agree with everything that Mark has to say.  However, here is just one site regarding this type of treatment.  http://www.legacyhealth.org/body.cfm?id=1051

There are many more sites that talk about the advances of Novalis. Its up to everyone do to their own research and be confident with their choices.  I just wanted to add another option.

[Mark]

It doesn't surprise me at all ( nor does it make an impression) to have a hospital such as legacy tout the system it invested in (Novalis) as the greatest thing since sliced bread. It wouldn't take more than 15 minutes to find similar articles celebrating CK , GK or anything else on google by other hospitals ( I know because I just did it  ). Peer reviewed clinical studies are always a more reliable reference than hospital advertising pieces as a rule. Actually, I did not think the Legacy article necessarily conflicted with many of my previous points. It makes no reference to CK, but it's only reference to GK deals with the ability to fractionate as an advantage which is true. It's other claim is that it is the "gold standard" for shaped beam technology which is probably true since neither GK or CK are considered as that.

While not a clinical study I did find what I would consider a pretty objective comparison of CK, GK and IMRT systems including Novalis. Everyone can read through and make draw their own conclusions as to capabilities keeping in mind that the ( N/A) next to GK merely reflects that it is limited to skull based tumors


http://www.sdcyberknife.com/dr-comparison.htm

Each of these machines are very capable of treating an AN but there are differences and at the end of the day you get to decide which do or don't make a difference to you

Mark

[Kilroy1976]

Crystallady:

Notice that the legacy health website is the website of a facility that uses the Novalis machine. For several reasons, some honorable and some not-so, they are not going to say that the Novalis is second-best. Some of Mark's quotes come from websites dedicated to promoting the cyberknife, and they likewise won't say the the cyberknife is second-best. The brochure that my hospital gave me for their Linac Scalpal made it sound as if I'd be an idiot to choose another machine.

Mark has been giving out good information on this board for a long time. What he says is backed by studies that he has read and, in many cases, graciously posted. He really is a blessing, and you'd do well to pay attention to his comments. However, even with medical testing, there is a need to exercise care. For example, there is a wretched excuse for a "study" out there that determined that there is no difference in control rates between radiosurgery and no treatment at all. It's BS of course, but unless you read the study carefully it might sound plausible. Personally, I would like to see more long-term studies with larger numbers of patients before conclusions are drawn, but that's just me.

If you're confident in the Novalis, that's great. I'm sure your doctors, and the machine, will do a super job. However, I feel that you'd be selling yourself short if you base your decision solely upon the statements of Novalis-promoting websites and Novalis-operating doctors.

We all wish you the best!

[Mark]

OK, my absolute final comments on the machine comparisons. My initial point regarded accuracy differences. Below is the response to my Question from Dr. Medbery

Look no further than the Novalis website. Their own data shows a BEST accuracy of about 2 mm. Depending on the size of the AN, that could be a substantial fraction of the tumor size. In other words, with a 6 mm tumor, you could miss one-third of it with Novalis. Actual accuracy in general use may be worse than 2 mm, since that is the best. Compare that to CK (0.89 mm very repeatable) and GK (probably 1-2 mm total accuracy).

Boy, I'm going back into retirement, I hit the board for one day and see what happens  

mark

--------------------------------------------------------------------------------
Clinton A. Medbery, III, M.D.
St. Anthony Hospital Cyberknife Center
(405) 272-7311
buddy@swrads.org or cmedbery@coxinet.net

[Mark]

Thanks Kilroy,

I think you hit the key issue right on the head ( or inside the ear for us ANers). whether you choose radiosurgery or surgery or any particular machine the key is determining what approach and what team you are most comfortable with. That is more meaningful than anything else

Good luck

mark