Proton vs CyberKnife Therapy for Prostate Cancer

by | Jul 1, 2022 | Proton vs CyberKnife for Prostate Cancer

Both CyberKnife and Proton Beam are forms of Radiation Therapy:

Here are the differences: CyberKnife Stereotactic Body Radiation Therapy (SBRT) typically emits 150 to 200 small x-ray beams, all penetrating the prostate from multiple angles resulting in a higher localized dose. That dose targets the exact shape of the prostate which means a minimal dose of radiation affects surrounding healthy tissue, resulting in much fewer, if any side-effects.

Proton beams deliver a lower dose of radiation to the prostate so a lot more treatments are required to a larger treatment area.


CyberKnife therapy uses only 5 treatments. Each treatment fraction is a much higher dose than given with Proton therapy. This is called hypofractionated treatments.

Proton treatments use conventional fractionation with small doses given daily over a 4-to-6 week period.

CyberKnife beams are continually image guided throughout the entire treatment so the robot adjusts for any slight movement the patient makes. That allows the CyberKnife beam to follow the prostate’s movement even as the patient breathes normally. If the movement is large the CyberKnife will suspend the beam until the patient is back in alignment. This allows for precise targeting of the prostate in an approximately 2-to-5-millimeter area surrounding the prostate.

Proton beam treatments do not have continual image guided technology, therefore the equipment can not make adjustments when the patient or the prostate moves, which happens naturally just by breathing. Therefore, a larger treatment  area, other than just the prostate is treated to compensate for this uncertainty. The target is usually the prostate plus 10-to-15 millimeters all around the prostate, which can result in more side effects.

Also, gas bubbles in the intestines and the bladder filling can move the prostate during treatment, sometimes up to 20-millimeters. That’s also why Proton treatments rely on a bigger treatment margin to keep targeting the prostate. Since CyberKnife uses continuous image guidance to correct for any prostate motion or patient movement it can target just the specific pin-pointed area.

A growing body of evidence from decades of clinical studies using CyberKnife hypofractionated radiation treatments (high dose in 5 treatments) shows that CyberKnife provides more effective treatment compared to Proton beam’s conventional lower dose fractionation treatment for (4-to-6 weeks).

A six-year study by Dr. Alan Katz published in the journal, Radiation Oncology nearly 10 years ago, in 2013 confirms that using high dose hypofractionation radiation therapy with CyberKnife is as good or better than the prodacted low dose conventional fractionation treatments with Proton beam and the toxicities to the bladder and rectum are lower using CyberKnife Therapy.

Here is a link to the published article.

Another Benefit: The cost of CyberKnife Therapy is a small fraction of the cost of Proton Treatments.

And CyberKnife is most often covered by insurance, Proton may or may not be. It depends on your insurance carrier. Make sure you check first or you could end up with a big medical bill.

For low to intermediate risk prostate cancer, both of these treatments have a very high local control or cure rate and are much better than conventional radiation therapy, which can result in very difficult side effects and requires 42 treatments over a 3 month period.

CyberKnife is available locally at the CyberKnife Center of Miami and has successfully been treating thousands of patients including those with prostate cancer since 2003.

We have the most experienced cancer treatment team in Miami because we have been doing it the longest. And it’s all we do every day!

The vast experience among our team allows us to take on the toughest cases.

Call us with any questions. Our compassionate team is happy to help you and your family every step of the way. 

Our goal is to get you treated as effectively, safely, easily and quickly as possible with the least disruption to your life, so you can get on with your life and put cancer behind you.

You can reach CyberKnife Miami at 305-279-2900 and go to our website for a lot more information about cancer treatment in Miami and the best doctors for prostate cancer treatment in South Florida.