Proton therapy - Was Re: Cryoablation-- a good, if not solid, bet?

[Guest guest]

gamlingman wrote:

> I am in the middle of Proton Therapy and so far no issues.

> This was on just the other night regarding other uses for

> proton where they state they need more data I believe they are

> speaking to the data on brain tumors not prostate as it is well

> into its second decade of use.

> Great video though and I can personally attest to its ease of

> being treated with hope that when its all said and done I am

> cancer free.

> http://www.cbsnews.com/video/watch/?id=6522160n

That was an interesting video.

As I understood the article citations posted here earlier, the

biggest controversy over proton therapy involves prostate cancer,

not pediatric cancers. The controversy is not over whether it's

safe and effective, but whether it is any safer or more effective

than x-ray radiation.

Proton therapy does seem safe and effective for prostate cancer,

but it costs more than x-rays, perhaps twice or even three times

as much. What do you get for the extra cost?

The idea behind proton therapy is that a very high percentage of

the radiation energy is deposited in the target region, whereas

with x-ray beams, a lot is deposited in healthy tissue in front

of and behind the prostate target.

All of that is true, but x-ray techniques are much better than

they were 20 years ago. Brachytherapy puts radioactive seeds

right in the target area and relatively little gets out of it. 3

dimensional conformal radiation and it's many variants (e.g.,

IMRT, IGRT, Cyberknife) use many different angles and intensities

in order to be sure that the prostate gets much more radiation

than any particular tissues outside it. Furthermore, for some

patients, radiation is directed outside the prostate on purpose

in order to treat the area around the prostate and the seminal

vesicles - something that is done with x-rays even when protons

are the main treatment modality for the prostate itself.

Finally, some of the key side effects of radiation have nothing

to do with damage to tissue outside the prostate, but with damage

to the prostate itself. Impotence and urinary restrictions are

both due to prostate radiation and, even in theory, proton

radiation offers no advantages over x-radiation in that area.

Both saturate the prostate with high energy radiation. Both kill

of tissue inside the prostate and cause inflammation and damage.

If they didn't, they wouldn't be effective.

Prostate cancer is the bread and butter of proton radiation

clinics. The number of prostate cancers is far greater than the

number of other types of tumor for which proton radiation is

essential - such as pediatric brain tumors and eye tumors. A

couple of 150 million dollar proton centers would presumably be

enough to treat all such tumors in the U.S. Spending another 1-2

billion to build centers for treatment of prostate cancer may not

be warranted if x-radiation clinics can be built for 10% or less

of the cost. But now that we have so many proton centers, with

more under construction, the hospitals and clinics are under

great financial pressure to pay off the loans and pay operating

expenses. The only way they can do that is by convincing

prostate cancer patients to be treated with protons.

As a patient, choosing proton therapy is a perfectly fine choice

- if you have money or insurance to pay for it. If you don't,

and you prefer radiation over surgery, then there are many x-ray

modalities that should be equally fine choices. You can pick a

good one from a good clinic and not be concerned that your chance

of success or your side effects will be measurably worse.

For the insurance companies and for Medicare however the

situation is more complicated. Should they pay $100,000 for

treatment when there is evidence that a $40,000 treatment will

work just as well and be just as safe? Should premiums be raised

on all patients to cover it? Is this an example of why costs of

medical care are skyrocketing while results are not improving

commensurately?

A lot of insurance companies have doubts about the cost

effectiveness of proton therapy for prostate cancer, but they

haven't wanted to go through the battles to fight it. However as

the number of PCa patients demanding proton therapy increases,

the insurance company incentives to fight go up too.

That is my understanding of the controversy.

Alan