Gammaknife v. Cyberknife - 1253923

Hi tjames:

While waiting for the docs and moderators to come onboard, I thought I'd send you this link of a prior discussion in this regard (including valuable insight from Dr. Loiselle - - our radiation oncologist here at GRACE: http://cancergrace.org/radiation/topic/focused-radiation/

My understanding of gamma knife v. cyber knife is that they are very similar technologies...and, as you said, a particular institution's preference usually is the technology that they have.

When my Mom was treating, her primary oncologist was at the City of Hope (about an hour from my Mom's home). When she initially developed a brain met and required post-surgery radiation treatment to the surgical bed (from which the brain met was extracted), I contacted her Radiation Oncologist at the City of Hope and asked if he thought it would be a good idea for us to transfer her from the local hospial where she was admitted - - and which had a gamma knife machine - - to the City of Hope where they have a tomo machine (and no gamma knife machine). My Mom's Radiation Oncologist told me that the technologies for the purposes of my Mom's treatment were very similar- - and that in all honesty, he did not think that she would get an added benefit if she was transferred from the local hospital to City of Hope. And, my Mom, in fact, never had a recurrence of disease in that particular area of her brain after undergoing gamma knife.

Anyway, just wanted to share our experience with you.

Laya

tjames, It is my understanding that there is no evidence that they are different. They are made by different companies and have different sales pitches.

Dr. West stated, " To my knowledge, there are no studies that actually compare these different techniques. I think they differ more in marketing than actual outcomes. My medical advice would be to not get too caught up in the hype, which would imply that there is actually some meaningful difference in how various branded SRS techniques differ. There is no evidence that shows this to be the case." in this very detailed discussion on the subject, http://cancergrace.org/forums/index.php?topic=10185.0

Janine

I still feel that way and am nearly completely certain that the only differences that are conveyed have no basis in medical evidence and are much more based on market forces. They're both perfectly capable of doing the same job, even if there are minor differences. If you needed a taxi to the airport right away and a Toyota pulled up, you wouldn't generally tell them to go ahead and wait for a different model because you only want a Ford. There might be a difference between a Toyota, Honda, and Ford (pick the car of your choice here), but they'll all serve your immediate needs the same and get you to the airport just as well.

-Dr. West

I like Dr. West's analogy so much I might start copying it. And, I strongly agree. The different forms of SRS are far, far, far, more similar than they are different. They all focus radiation in a very similar way and with similar efficacy.

I had never come across either of these terms until I started reading posts on GRACE. In the UK we generally just call it "radiotherapy" or "SRS" (stereotactic radiotherapy").I find the "knife" part very odd - as if this were some sort of surgery.
tjames, for what it's worth, I've had radiation at two different hospitals, and what mattered to me was the ethos of the department. One was calm and ordered, the other rather haphazard (which did not inspire confidence). So those are the criteria I would use.

Gamma Knife and CyberKnife are equal in out comes. Gamma Knife uses cobalt radiation and CyberKnife uses high dose xray beam radiation (using a small linear accelerator). The differences are that Cyberknife can treat tumors anywhere in the body and Gamma Knife cannot. Gamma Knife uses a head frame that is bolted into the skull with screws and is limited to a single fraction while CyberKnife uses a thermoplastic mask to hold the head in position and therefore can allow for more than one fraction. Typically one to five fractions are used. More fractions are used if the tumor is large or if it is in close proximity to critical structures like the brainstem or optic nerve.

Cyberknife is used to treat brain, spine, lung, liver, prostate, and pancreas since 2003. It uses realtime imaging of the target and respitory tracking to treat organs that move with respiration. No other radiation therapy has this capability.

For Acoustic Neuroma's Dr John Kresl, Nationally Recognized Radiation Oncologist in Phoenix Arizona, was involved in a comparison of Gamma Knife VS. Cyberknife (for Acoustic Neuroma). Because Cyberknife does not use the bolt on head frame, it can deliver the radiation in the same massive dose Gamma Knife does, or treat over 1 to 5 fractions. The study showed the lower dose treatment had the same success in ablating the AN, but had much higher success of preserving the patients hearing. The large dose of the Gamma Knife showed a lot of patients losing their hearing, in comparison to Cyberknife. They are both pin-point, sub-millimeter accuracy treatments.