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Proton vs Photon

"proton versus photon" "proton radiation" "photon radiation" "brain radiation" "brain cancer" "meningioma"

If radiation therapy is a part of your treatment plan, I'm sorry. It's awful, it really is. But it can be okay and a whole lot less scary if you're well informed and feel confident about the type of treatment that you and your doctors decide on. Read on to see how I decided on Proton therapy.

Once they removed my tumor and found out that it was grade III anaplastic (the worst kind), my doctors told me I had two options for radiation: proton or photon. I was foggy from the meds, angry about my diagnosis, and just generally confused, so I asked my doctor to summarize the biggest differences between the two. Like, get to the point and make it simple. So here it is in the most simple and accurate terms:

Proton therapy delivers a more targeted and precise dose of radiation, so it damages normal cells less, and may cause less side effects.

Interesting, eh? I certainly thought so. Who doesn’t want “less” potential brain damage? Finally, something that resembles decent news - I might get to spare some brain cells. I got comfortable in my seat, leaned in and wanted to know everything about this proton stuff. And that began a long conversation about the difference between proton and photon therapy, and which is better. Some key areas where protons and photons differ can be found in the way they actually deliver the radiation, the cost of the treatments, and the side effects. We weighed each of these issues and ended up deciding on proton. Here's why!

Different delivery methods.

Traditional photon radiation therapy uses x-rays to attack cancer cells. The machine delivers these x-rays, or beams of photons, to the tumor and beyond it. Photon beams don't stop at the tumor, so as the beams exit, they hit normal cells and tissue. I don't see how this could ever be a good thing, but it seems especially daunting when those "normal cells and tissues" are brain cells.

Proton therapy, on the other hand, stops at the tumor. There is no exit dose. I didn’t quite understand how this was possible. How did the radiation beam just STOP? But it does, and as a result, it is less likely to cause damage to the surrounding tissues. Less damage to the surrounding areas of the brain means less potential side effects during and after radiation treatment. At this point I was comfortably seated on the proton bandwagon but there was still the side effects and cost to consider.

Side Effects. First, there's the overall disclaimer for any type of brain radiation - it "may" cause fatigue, swelling at or near the treatment site, headaches, hair loss, and radiation burn. I get it - I'm a lawyer. You have to say "may" cause. But it's not "may" cause. I'm here to tell you as someone who has been through it, it definitely causes most if not all of the side effects, just in varying degrees.

The side effects, or severity of them may vary depending on the type of radiation. The photon beams don't stop at the tumor so they hit normal cells and tissues on their way out, and can cause damage to healthy tissue around the tumor. For me, this meant potential vision loss/blindness, hearing loss, thyroid problems, neurocognitive deficits, and a few other things that I honestly can't remember. The doctors said I would definitely lose my hair, I might feel tired and I would get radiation burn, but that everything should resolve after treatment and my hair would probably grow back.

Proton therapy is the same in that it causes all the typical radiation side effects, but the side effects to the affected areas can be stronger and more permanent with proton therapy. Because the proton beams are so targeted and so precise, they would deliver the full dose of radiation to a concentrated area, causing stronger side effects in that area. Among other things, I was told my hair would probably NOT grow back and my radiation burn may be more severe and visible forever. As hard as it was to accept the "probably" permanent hair loss and forehead discoloration, we decided that it was more important to spare critical areas of my brain. Proton was still in the lead. (Fyi: my hair DID grow back, and it's still growing back, so don't lose hope!!!)


Proton therapy is considerably more expensive than traditional photon radiation. Unfortunately, not all insurance policies cover proton therapy and even if they do, you could still get some push back from your insurance carrier. Go over your insurance plan ahead of time and know what kind of plan you have. If your insurance denies coverage for proton therapy you might have to go through an appeals process and your radiation oncologist can help. I have great insurance and they still didn't want to cover proton therapy since there was an available cheaper option. My doctor helped by submitting all the medical reasons I needed proton over photon to the insurance company and they finally agreed to cover it. The National Association for Proton Therapy is a great reference if you are trying to get your insurance company to cover your proton treatment.

My doctors all felt that proton therapy was the way to go, and after considering all the factors of each treatment, my family and I agreed. It really came down to which method would kill any remaining cancer cells while preserving as much healthy brain tissue as possible. But, even though proton therapy was right for me, it may not be for you. Cancer is very case specific! It is so important to gather all the information you can, do some research and rely on your support system and doctors.

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