Protons, Prostate, and the New York Times

[Guest guest]

An article today in the New York Times spoke about proton therapy for

cancer--including, of course, prostate cancer.

Not the most positive article--it talks about the expense of the

facilities, and compares the overall effectiveness (accuracy, relative

lack of side effects, etc.) to IMRT.

http://www.nytimes.com/2007/12/26/health/25cnd-proton.html?

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tner=rssyahoo & emc=rss & adxnnlx=1198630859-dY9+G9j+C7n4U69AsArZrg

(You'll probably need a free subscription)

--Steve

[Guest guest]

Does anyone know if rad onc Dr. Zeitman at MGH/Harvard works with

tradiational radiation or with Proton Beam toys?

If the US can spend hundreds of billions of dollars to fight a war

for oil in the middle east, then it can spend a few billion for

proton beams. I had PBRT and my goodies didn't get fried. Most PBRT

nay-sayers point only to marginal improvement in outcomes to justify

their position that it costs too much. QOL after treatment is as

valuable or more valuable than outcome. If it wasn't, then a simple

surgical castration and cremation would be the " cheapest " way to go.

I wonder which treatment Dr. Zeitman will choose if he is dx'd with

prostate cancer . . .

>

> An article today in the New York Times spoke about proton therapy

for

> cancer--including, of course, prostate cancer.

>

> Not the most positive article--it talks about the expense of the

> facilities, and compares the overall effectiveness (accuracy,

relative

> lack of side effects, etc.) to IMRT.

>

>

> http://www.nytimes.com/2007/12/26/health/25cnd-proton.html?

>

_r=1 & ei=5089 & en=df70e491e0fa0d00 & ex=1356325200 & adxnnl=1 & oref=slogin & pa

r

> tner=rssyahoo & emc=rss & adxnnlx=1198630859-dY9+G9j+C7n4U69AsArZrg

>

> (You'll probably need a free subscription)

>

>

> --Steve

>

[Guest guest]

edited

In the article that Kathy comments on is the following paragraph:

" Proton radiation is reported to have several advantages over

traditional x-ray radiation. First, the success rates reported in the

limited literature available suggest that it is a more effective form

of radiation therapy. Second, proton radiation can clearly be

targeted more precisely than traditional radiation, thus minimizing

the loss of normal tissue and harm to nearby organs (e.g., Hug, 2004;

Slater et al., 2004; Suit et al., 2003). Third, proton radiation can

be safely administered in higher doses than traditional radiation

(e.g., Zietman et al., 2005; Hug, 2004). "

My research has indicated that:-

The Bragg peak effect " stops " the radiation at the target, and

releases the energy there. Thus the damage that occurs when X-ray

radiation travels on through the body and other organs in the path of

the scattering X-rays does NOT occur with protons.

Dr. Zeitman is indeed at MGH, and is a proponent of proton radiation

treatment for most other cancers than prostate. He would prefer that

prostate cancer patients be treated with IMRT, primarily I believe,

because MGH does not have the treatment capability (in capacity –

number of treatments per day) that some other centers have, and he

believes that the proton machine should be used to treat some of the

other life threatening cancers of perhaps higher priority.

As to comparisons, I have quoted this article before, but here again

is a study comparing protons with X-ray photons and IMRT:

" Results: With photon- and proton-based radiotherapy techniques

similar dose distributions were determined for PTV I-III: mean and

maximum PTV dose values were between 99-104% and 102-107% of the

normalized total doses (70 Gy), respectively. Conformity indices

varied from 1.4 to 1.5 for the photon techniques, whereas for proton-

beam radiotherapy values ranged from 1.1 to 1.4. Both the 3-D

conformal and the IMRT photon treatment technique resulted in

increased mean doses ( & #8764; 40-80%) for OARs [Organs At Risk] when

compared to protons. With both photon techniques non-target tissue

volumes were irradiated to higher doses (mean dose difference > 70%)

compared to proton-beam radiotherapy. Differences occurred mainly at

the low and medium dose levels, whereas in high dose levels similar

values were obtained. In comparison to conformal 3-D treatments IMRT

reduced doses to OARs in the medium dose range, especially for the

rectal wall. "

Fuller

[Guest guest]

This is exactly what I would expect Fuller to post. This argument is

getting stale.

Blair