Traditional Radiation therapy -- used everywhere/Proton Radiation therapy more targeted, safer --only in five or six centers in the U.S.

[Happystrap]

Persons prescribed radiation therapy need to know the difference between photon and proton. The proton radiation does not burn you all the way in and beyond the target. If possible refuse the traditional radiation and choose the other. Its been around for about 30 years, though some insuraqnces claim (falsely) that it's expiremental.

[FCoffey]

There are at least 35 proton beam therapy (PBT) centers in the US, many of them have more than one patient treatment room.

There is a map:

proton-therapy.org/map/

There are good and bad aspects to everything. I've designed some of the equipment used in modern proton beam therapy machines.

Yes, the proton beam deposits more of its energy in the tumor, less in the intervening tissues.

Many PBT machines spread the energy out with a diffuser, with also spreads the beam spatially and degrades some of that precision, in both up-down/left-right and depth.

Those few centers with pencil-beam capabilities can draw your own tumor with the beam.

But that pencil beam is extremely powerful; if off by as little as 0.3 mm it can be burning things it shouldn't, and doing so a lot faster than regular radiation therapy.

How much does the typical patient move? About 3 mm.

I talked with the doctor who developed pencil-beam proton therapy in the US. He's quite smart. He didn't recommend it for my case.

It's not for everyone. It's certainly an option for those considering RT. It is FDA approved and therefore by definition not experimental, but you may have to go through some appeals with your insurance company to get it covered.

The studies to date suggest that PBT is about the same as traditional radiation therapy in terms of effectiveness. No worse, but not a lot better either.

Since the PROTECT trial showed that 33 men would need to be treated with radiotherapy rather than receive active monitoring to avoid 1 patient having metastatic disease after 10 years, the odds of either type of treatment (PBT or conventional RT) conferring that benefit is about 3%. Even if PBT is a bit better than conventional RT, those are still lousy odds..

[farmanerd in reply to FCoffey]

Just looked at the video on the page in the following link and the equipment that does PBT is amazing -- I'm having an engineering geek moment!

[farmanerd in reply to farmanerd]

siteman.wustl.edu/treatment...

Sorry, forgot to include the link.

[FCoffey in reply to farmanerd]

That's the model I worked on. PBT facilities are basically relativistic proton accelerators, about 230 MeV or so.

You can see more at

mevion.com/why-proton-therapy

[mchale in reply to FCoffey]

Thank You for detailed explanation about the collateral damage with pencil beam using CT guided targeting which can only sample the position of the prostate every two minutes….. and during that time span due to gas or bladder volume your prostate could move as much as 6 mm.

MRI guided Linac on Meridian or Electra the prostate is sampled every 4 to 6 times per second real time and Linac accelerator has gating and real time imaging that shuts off radiation anytime the prostate moves out of the target area.

[Tall_Allen]

So far, proton has failed to show any advantage over photons in clinical trials, but none have been randomized so far. It is a big stretch going from the Bragg peak theory to no evidence of clinical toxicity - in fact, there is. I'm agnostic on whether proton is more or less toxic than photon, but you would think that a therapy that has been around for 30 years would have better comparative data. I think insurance companies are right to turn down this very expensive therapy until there is better comparative data. See the table in this article:

pcnrv.blogspot.com/2016/08/...

[Happystrap in reply to Tall_Allen]

Maybe no notable reportable advantage relative to "cure" of the cancer...but there is a substantial advantage with respect to general tissue damage unrelated to the target, and the patient seems to have far less residual after-effect, and the immediate post-treatment effects on the patient seems almost non-existent (based on my experience and on the experience of others with whom I became familiar during my concentrated treatment period). Don't know if people with photon radiation treatments can undergo the same "concentrated" treatment period.

[Tall_Allen in reply to Happystrap]

Did you look at the chart? Where do you see any healthy tissue advantage? I was treated in just 5 treatments- no lasting side effects whatever.

[Hidden in reply to Happystrap]

Here's the data from a large retrospective study on the subject of side effects for proton vs. IMRT photon beam treatment.

Here's a quote:

We identified 27,647 men; 553 (2%) received PRT and 27,094 (98%) received IMRT. Patients receiving PRT were younger, healthier, and from more affluent areas than patients receiving IMRT. Median Medicare reimbursement was $32,428 for PRT and $18,575 for IMRT. Although PRT was associated with a statistically significant reduction in genitourinary toxicity at 6 months compared with IMRT (5.9% vs 9.5%; odds ratio [OR] = 0.60, 95% confidence interval [CI] = 0.38 to 0.96, P = .03), at 12 months post-treatment there was no difference in genitourinary toxicity (18.8% vs 17.5%; OR = 1.08, 95% CI = 0.76 to 1.54, P = .66). There was no statistically significant difference in gastrointestinal or other toxicity at 6 months or 12 months post-treatment.

Conclusions

Although PRT is substantially more costly than IMRT, there was no difference in toxicity in a comprehensive cohort of Medicare beneficiaries with prostate cancer at 12 months post-treatment.

academic.oup.com/jnci/artic...

[FCoffey in reply to Hidden]

I've read that study. What struck me is how casually they dismiss the benefits at 6 months. Inflicting an additional 6 months of suffering on generally older men with limited lifespans means nothing at all, money is all that matters.

[Hidden in reply to FCoffey]

From the study, it looks like 3.6% of proton patients has a 6 month benefit. Hard to justify almost double the cost.

Money isn't all that matters, but I don't think we should support treatments that add a negligible benefit at a huge price difference. We are all paying for it.

[FCoffey in reply to Hidden]

From the much larger PROTECT trial, about 3% of RT patients gain the benefit of not having distant metastases after 10 years. There is no difference in overall survival compared to active surveillance. I agree that we shouldn't support treatments that add a negligible benefit at a huge price difference and with major QOL losses. Using the same standard, it would be hard to justify those costs. So why are we doing RT at all?

Yes, we are all paying for it, but some pay more than others, in ways that are not measured in dollars.

The difference is where the money goes, not the effectiveness of the treatments.

[Hidden]

Protons are no better than photons in terms of effectiveness and side effects. They are heavily marketed as being better "in theory" but as the saying goes "In theory, there is no difference between theory and practice; but in practice, there is."

They are superior for certain cancer treatments, but it's not enough to justify the high cost. So it's marketed to other cancer treatments to help cover the cost.

[Fairwind]

It works good on very small and hard to reach cancers...But for most Prostate Cancer where the target is much larger, a "pencil beam" is not the most effective treatment. Efforts to spread out the beam have resulted in less than ideal results..

[FCoffey in reply to Fairwind]

Yes, for certain cancers of the eye, spine, and brain PBT works like nothing else. Prostate is the big money maker at PBT facilities, but that revenue enables life-saving treatments for those other, very serious cancers.

[bobdc6 in reply to FCoffey]

Agree, when I had my 39 proton treatments at Provision (Knoxville), I was told that the main customer there was the child with cancer. We old PC guys were scheduled late in the day with the kids and their worried parents going in early. I was more than happy to support the technology since it helped out those kids. Super conducting magnets are making proton smaller, cheaper, and more efficient.

[Hidden in reply to Fairwind]

I went to a center that had both systems and they chose the proton for my tumor. I questioned why and what I understood was that the location of the tumor near my rectum was better treated with the pencil beam. I hope they were right. On the insurance matter if Medicare covers it and they do,Blue Cross plan 65 covers it. I’m sure it is all in how the drs word the need. After listening to others here I think the whole pelvic radiation may have treated the areas that were suspect better. The whole issue for me is I didn’t do the pet scan to find any and all cancer locations before they drove my psa down with the drugs. I jumped in with both feet before I understood what was available and they didn’t offer it. That’s what we do question question question then sit around and wait for the psa to move.

[jfoesq]

Unitedhealth (Oxford) denied my doctor's request for the PBT when I received radiation approximately 5 years ago, claiming there was a lack of scientific evidence indicating it was any better. Fortunately, I didn't suffer any complications that often times occur with radiation. Recently,Richard Cole, a prominent lawyer in Florida filed a lawsuit and requested a "class action" be approved in a case agst his Insurance company, Unitedhealthcare, which denied him the PBT. I believe the suit is pending assignment to a new Judge, (as the first Judge recused himself, since I believe he also has PCA.) It will be interesting to see if the "class action" is approved and what happens as a result of the lawsuit.

[j-o-h-n]

youtube.com/watch?v=west2PF...(Not working as expected?)

Good Luck, Good Health and Good Humor.

j-o-h-n Thursday 05/30/2019 11:12 PM DST