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Comparison: Proton Therapy & X-Rays

For decades, X-rays have been the radiation used to treat cancer. But there are some problems. For example, they go all the way through the body and don't stop, damaging healthy tissue in the process. Protons, on the other hand, require a lower dose upon entry, and then release their energy in a huge burst, called the Bragg's Peak. That's it. They stop. There is no exit through the body.

Below is a graph showing the dose, which is to say, the amount of radiation. You can see that X-rays start with a high dose, because, having virtually no mass, they stray and get absorbed by the body on route to their target. In contrast, protons are heavy. Consider a hydrogen atom, which has one electron in the outer orbit and one proton in the nucleus (center). If the electron weighed 175 pounds, as I do, the corresponding proton would weigh sixty tons. Tons! This is the same kind of relationship between x-rays and protons. In addition, the protons have a positive electrical charge. When they enter the body, they grab electrons from surrounding tissue in order to regain their stability. As the protons slow down (relatively speaking), they reach a point at which they gain the rest of the electrons in a big burst of energy. This creates a peak of energy, as shown in orange below, called the Bragg's Peak. As we will see, protons do many things that X-rays cannot. That's why this page is dedicated to making a comparison between the two modalities.


The above graph (courtesy of IBA) compares one x-ray beam and one proton therapy beam. In reality, numerous proton beams combine to form what is called the Spread Out Bragg's Peak, or SOBP. Below is a more sophisticated way to see these relationships (also courtesy of IBA).

Notice on the left side scale, the green area, representing the prescribed dose, reaches an effective relative dose of 1.0. The blue line represents the SOBP, which never goes higher than the full dose. Photons (X-rays) on the other hand start at 1.88, almost twice the needed dose, to achieve a target dose is 1.0. There are technologies to spread out the X-ray doses so such a high dose is not necessay, but as you will see below, they still affect a lot of tissues which you would rather keep healthy.


In my hurry to publish the first editions of my books, I was lax in getting the proper permissions and attributions for the illustrations I used. When such permission was not forthcoming, I needed to get new ones. The Proton Therapy Center in Prague, the Czech Republic, graciously came to my rescue. They provided illustrations that portray a number of cancers, showing the difference between X-rays and protons. X-rays are also called photons. So we have pRotons vs. pHotons. Besides the graphs below, from my books, I also received some technical graphs too detailed for the books, but which I will include on this website. See the link at the bottom of this page.


All of these illustrations follow the same pattern. First is photons showing how much healthy tissue is affected by X-rays. In both protons and photons, the tumor is covered 100%. That causes some people to declare that they are equal. Yes, they both kill the cancer, but at what price? Look at how much of the bladder and rectum may be impacted by X-rays. Which type of radiation would you rather have?

For purpose of illustration, this shows none of the protons affecting the rectum. But if you look closely at the illustration, you will see that they do touch a part of the rectum. I had an injection of a product called SpaceOAR, which puts a hydrogel spacer between the prostate and the rectum. The result is that the rectum was indeed spared. The latest development in proton therapy, pencil beam scanning, requires a margin beyond the tumor of only a few millimeters, which is about the thickness of a quarter.

This is a drawing made of my actual organs, made from my CT and MRI scans. (See my experience.) The yellow area is the bladder. The U-shaped red area is my lymph nodes, which were also treated just in case the cancer had spread to them. (The white is bone.) X-rays would go right through the bladder. Proton therapy, however, can be directed from each side so that the bladder is not hit. X-rays are directed from several directions and go all the way through the body, directly affecting the rectum and bladder. This same situation is reflected over and over again in the cancers illustrated below. Protons are like smart bombs, X-rays are like carpet bombs.

IMRT on the left means Intensity Modulated Radiation Therapy, in which X-rays of lower doses are directed from numerous sides of the tumor, in smaller doses. They converge on the tumor, which gets the total cancer-killing dose. Large areas are subjected to smaller doses. On the right, IMPT stands for Intensity Modulated Proton Therapy. Here the prostate is treated from each side, similarly overlapping on the tumor.




Even the critics acknowledge that protons are superior when it comes to treating the brain, due to all of the sensitive organs in close proximity. This is especially true for children, whose brains are still growing and can be stunted by X-rays.

At the end of my book on 80% of all cancers, I review a book that tells the dramatic story of Ashya King whose doctors in England prescribed X-rays and chemotherapy in a way that would have left five-year-old Ashya a vegetable. The family fled to Spain on their way to Prague to get proton therapy. The parents were arrested in Spain and put in jail, until there was such a public clamor that they were released. They made their way to Prague and received their treatment. Now, going on four years later, Ashya is in school, living the life of a rambuncious young man, rather than being confined to a wheelchair. His doctors in England made many outrageous statements against proton therapy, which weren't true. This incident led to a doubling in the number of inquiries the proton center in Prague received from parents concerned about the treatment their children would receive.

Getting this link, I found that Saving Ashya by Naghmeh King has a new edition. Here is how they describe their story.

Ashya King sparked an international manhunt in 2014 when his parents Brett and Naghmeh King removed him from NHS (National Health Service) care at Southampton University hospital, to undergo pioneering proton treatment at the Proton Therapy Center in Prague. Ashya had been diagnosed with a medulloblastoma, an aggressive grade 4 type of brain tumour, which was successfully removed by surgeons in Southampton on 24 July. He then had a further operation on his brain on 22 August.
As a result of these procedures he was unable to speak, unable to eat or drink on his own and relied on a food pump.

In order to help prevent a return of the tumour, his parents wanted him to be given proton beam therapy - a treatment the NHS does not provide in the UK, although it does refer patients to other countries for treatment.They were arrested in Spain and held by police for 3 days before eventually being released and allowed to continue their journey. Ashya was made an award of court and only after 2 further court hearings at the family courts in London, where it was confirmed that the treatment wanted by Ashya's family was both valid and deemed beneficial . Three years later and Ashya’s family say he is now back at school and cancer-free.

My point in dedicating so much space to one story is to demonstrate how many barriers some people must overcome to get proton therapy. In the United States, insurance companies contiue to resist coverage, and doctors fail to recommend it. Patients must stand up for themselves and find their proper treatment, despite the misinformation that surrounds them.





I dedicated my second book to my deceased wife Ruth Hanna, who died of breast cancer in 2007. Proton therapy existed then, but we never learned about it. Had we known, perhaps she would still be alive today. I remember reading of a woman in Florida diagnosed with breast cancer. She died after being treated with chemotherapy and radiation. The subsequent autopsy showed there had been a wrong diagnosis. She did not have breast cancer at all. It was the treatment that killed her. For five years Ruth and I battled her cancer using alternative treatments, even going to Germany for a few weeks. After five years, we had made no progress, and so acquiesed to the doctor's program of mastectomy, radiation and chemotherapy. There followed a year of misery and suffering. My Ruthie died at home, under hospice care.

In treating left-side breast cancer, X-rays can damage the lungs and heart to life-threatening degrees. Proton therapy avoids that. The difference between the two is like night and day. As far as I am concerned, critics of proton therapy can go jump in the lake.



With GIT cancer, even protons can't avoid radiating some of the surrounding organs, but to a far lesser degree. This is one area in which protons have not been used very much. IBA conducted a survery of 222 hospitals about how they felt proton therapy could be used. Here are the results.

You can see that gastrointestinal cancer is close to the bottom. Yet, it is not zero, so it has been used in some cases. No matter what kind of cancer I had I would check out proton therapy. The 20% of cancers that can't be treated don't have identifiable targets, such as leukemia (blood) or widely metastacized situations.



I had a good friend who died of lung cancer. Again, no one told him about proton therapy. Notice how it can be used to treat the tumor from two directions, instead of many.





I think I have made my point in favor of proton therapy. Let me remind the visitor to this page that I provide these illustrations for informative purposes only. Individual results, as they say, can vary. Further, I am NOT giving medical advice. Go to your doctor for that. If he or she is not informed about protons, go to a different doctor. I know of one man who went to five doctors before he found one who gave accurate advice about proton therapy. I provide this information so you can investigate whether proton therapy is right for you or a friend or loved one diagnosed with cancer. If you want more details, my books are available on Amazon.com.

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Here is the link to far more technical illustrations on this same subject, comparing protons and photons:


Return to Photos Page.

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Our other websites are also of interest:

www.proton-therapy-centers.com (A list of proton therapy centers in the U.S.)

www.proton-beam-therapy.com (Our proton therapy blog.)