I came across Novalis radiosurgery. I have a feeling that it is similar to CyberKnife. Novalis was launched in 1997. It is more recent than Cybernife. Novalis started at UCLA while CyberKnife started at Stanford. Novalis is competing with GammaKnife (primarily for brain tumor). Do you have information on Novalis? My town has 2 Novalis centers but no Cyberknife.
Misleading or simply wrong information can be found in many places. Including major print media and the Internet.
Presently only the CyberKnife can deliver beams of radiation from a choice of nodes of 360% reference to the target. Why is this important? This allows beams to be selected to miss critical structures. All other machines deliver beams from a 2D plane. Physics limits the shape of the prescribed dose volume. This is a major advantage of the CyberKnife.
Respiration timing is "not" used in the treatment of prostate cancer. Prostrate movement during treatment is the result of solids and gases in the colon and liquids in the bladder. Respiration timing is used in the treatment of lung cancer and breast cancer with many new radiation systems. The CyberKnife uses respiration timing if, fiducials (targets) are not used to target the tumor.
The CyberKnife is the only radiotherapy treatment that tracks the prostate, with sub mm accuracy, during treatment. When the prostate moves the beam is moved to stay on target.
Only the CyberKnife tracks and automatically adjust the beams to keep on target. This allows the dose volume margin to be reduced, which reduces high dose to the colon and bladder.
Ionizing Radiation energy to cancer cells is measured in fraction size, number of fractions, and total dose. The biologic equivalent of dose per session is not linear. The size of the linear accelerator is not a measure of treatment dose. Hypo fractionation is the term used for a therapy that delivers high dose per session. Prostate cancer is more sensitive to increased dose per session/fraction than other cancers. This is a good characteristic that has resulted in better cure rates with increased dose per session/fraction. Hypo fractionation (HDR Brachytherapy and CyberKnife) has a very high cure rate relative to lower dose per session radiation. IMRT total dose has increased from 60 Gy to 80-86.4 Gy delivered in 1.8 Gy per session/fraction. Today the typical IMRT plan is 40-45 days of therapy. The CyberKnife has two plans four sessions of 9.5 Gy or five sessions of 7.25 Gy. The total does of hypo fractionation is less than 1/2 of the total dose from IMRT. The dose to normal tissue is lower with hypo fractionation plans and toxicity less.
Presently only the CyberKnife can deliver a hypo fractionated dose with sub mm accuracy from 1000's of nodes at 360% to the target. Other IMRT machines, by any name, can deliver a hypo fractionated but do not because of toxicity to normal tissue.
Suggest all men understand the science of radiotherapy. This is the only way to know if your are being mislead.
The way I read it, the Novalis Tx is able to give a higher dose rate -- 1000MU per minute. That might translate to less table time. It has rotating robotic arms along all 3 axes of motion. It also has ExacTrac XRay 6D adaptive gating that tracks intra-organ fiducials to precisely track tumor motion and treats with sub-millimeter accuracy. They both use hypofractionated doses to treat in 5 sessions. I really don't see a big difference.
The Novalis Tx is a gantry based system that can circle the target in 2 axis only. (single plane)
The CyberKnife can deliver beams from 360 degrees in x,y and z axis. There in "no" other system, today, with this capability.
The Tx does not automatically adjust before "beam on" during the session.
The limited x,y nodes choices limit treatment of PCa to low dose IMRT. The sessions are relatively fast 10-15 minutes, times 45 sessions. Present CyberKnife treatment for PCa are 40-60 minutes in four or five sessions. Let me know if there is any published data for the Tx used to treat PCa in 5 sessions of hypo fractionation. I would expect increased toxicity for patients if the Tx was used to deliver SBRT for PCa. Tx may be better than older systems but that is not proven in long or short term data.
If you want to compare the two consult with radiation oncologist the offer both treatments. Ask what margin is used in their treatment plan for the bladder and rectum.
My radiation oncologist HAS used both the CyberKnife at Stanford and the Novalis Tx at UCLA. He tells me the planning is done with sub-millimeter accuracy and the hypofractionated dose is delivered in 5 treatments. The more recent Novalis Tx is just an evolutionary improvement over CyberKnife. I'm sure there will be many more improvements in the coming years as those companies compete to "build a better mousetrap." We are very lucky to have options not available to us a decade ago.
Your doctor is one of Worlds best radiation oncologist for treating prostate cancer!
There is no doubt your outcome would be exceptional in his care.
Can he duplicate the outcome of the CK using the Tx? My vote would be yes.
With this Dr in control of the treatment delivery the Tx will do well.
Radio therapy continues improve, the gold standard is no longer surgery. The CyberKnife just takes the treatment planning and delivery to the next level. This sets the treatment bar higher for the other equipment suppliers and treatment providers. Hypo fractionation has excellent results, IMRT with today's technology is also very good.
We are lucky to have these advancements as treatment options.