Does anybody have an opinion to share about TomoTherapy?

I had to look it up, but this is just a refined delivery of photon radiation (x-rays) it seems.

This link http://www.tomotherapy.com/ should explain the differences between it and IMRT. As far as the differences between the 2 (proton and photon) my wife Cindy has started to describe it as photons burn their way in and out of your body irradiating everything in their path and protons treat only the prostate. A little simplistic maybe, but true. If you click on the link and scroll down to recent news you will see that the 2nd bullet is a news release about this company partnering with Lawrence Livermore to produce a low cost proton delivery system. Please read that as well. Feel free to ask if you have any more questions. I can answer them as technically as you wish.

Way off topic, but an interesting read. I used to work for and with a number of people who now run and manage TomoTherapy. This article, http://www.milwaukeemagazine.com/currentIssue/full_feature_story.asp?NewMessageid=12513, is about one of the board members.

same_as_u said...
Thanks John,

As I learn more it seems that the Proton therapy is not as precisely accurate as the Tomotherapy. What the result of this is, I have no idea.

Cindy's description sure helps.

Well the result of more accurate photon delivery via the Tomotherapy should be a lessening of the unwanted side effects of radiation in the first place. You must understand that with photons the beam starts to scatter and lose its energy as soon as it contacts the skin. This requires the dosage to be escalated as the prostate is about as deep in your body as it is possible for an organ to be. So in order for the prostate to receive an effective dose of radiation (effective meaning, kill the cancer) the level has to be pretty high as only 60% or so of the actual dose reaches the prostate. The rest irradiates the surrounding tissue and some exits the body entirely. The current theory is to deliver small managable doses of photons to the area to be treated as it is the total accumulated dose that provides the cure. It is also why photon and protons are delivered over time, say 40-45 treatments. If you were to deliver the total radiation dose equaling 76-79 Gy (gray) you would die outright of rad poisoning. 10-20 Gy administered full body at once is usually a fatal dose.

With Protons over 90% of the energy is delivered to the tumor site, in the case of the prostate it is delivered 3 dimensionally also called conformal treatment using a lens called a bolus that is made specifically for YOUR prostate by the treating team. Scatter is non-existant and no radiation passes through the body and unwanted radiated tissue is kept to a minimum. In fact one of the possible benefits of Protons is that a typical treatment regimen will include the margins of the prostate where cells that have already escaped may be lurking. Accuracy is generally within 1 millimeter in any case.

Actually I think a truer statement would be that Tomotherapy treatment is trying to mimic the delivery system of Protons in order to increase the accuracy of the treatment and minimize side effects, rather than the other way round. 

You should feel confident in choosing either modality for treatment. I personally, am choosing Protons.

It is tough to have to choose, isn't it? It is not like the Dr. will help with this decision and you never can be entirely sure that what you choose will be the best for you and present a cure, which is what we all seek. Take care and please if you have any more doubts, questions or whatever feel free to ask.

John

Walt:

Don't know much about Tomotherapy, but I do know that it is photon (Xray) which means that it is radiating as it enters and as it exits.

The March 2007 PAACT had the following article regarding proton vs IMRT(photon):

http://www.proton-therapy.org/documents/!Proton%20vs.%20IMRT%20PAACT%2003-07.pdf

 

Dutch