Saturday, May 30, 2015
Is Proton Beam Therapy Worth It?
Comparing degrees of localization of proton beam therapy with other treatment modalities, in terms of dose v, tissue depth. 'SOBP' denotes 'spread out Bragg peak' - or the collation of several such peaks via different beams, for different depths. Red line denotes depth dose plot of x-ray beam..
The Wall Street Journal article 'Making A Case for Proton-Beam Therapy', to treat cancer - actually posed an interesting conundrum. On the one hand "six new proton beam centers are set to start delivering state of the art radiation to cancer patients around the country by y ear's end" - with no fewer than ten additional centers expected by 2018 bringing the total to 30.
On the other hand, these centers are "entering an uncertain market" since the therapy still "lacks evidence that it is better than traditional radiation despite costing significantly more". Indeed, as the WSJ piece notes, Aetna and United Health Group, Inc. have stopped covering it for prostate cancer, "once seen as a main source of patients".
I also (briefly) considered getting proton beam therapy when my prostate cancer was diagnosed back in July, 2012. However, my wife (a former radiotherapy software specialist) convinced me that high dose rate brachytherapy - which her company specialized in - was the better option. Plus, she knew the best center in the nation to get it: the Helen Diller Cancer Center at University of California - San Francisco and had worked with the world-famous oncologists there . She was also skeptical proton beam centers existed that could give 100 percent assurance and confidence that through all the 30 or so days of treatment one would not see a "geographical miss". That is, the proton beam hitting a critical region like the bladder or lower bowel instead of the cancer, putting an unwanted micro-hole in either..
For those not aware, proton beam treatment is a form of external beam therapy in which positively charged particles (protons) are accelerated to 60 percent of the speed of light, or 180,000 kilometers per second. They are constrained to form a powerful beam that can be programmed to deposit most of its energy directly into a target tumor - say in the prostate gland - minimizing radiation exposure to surrounding healthy tissues (say bladder and lower bowel in the case of prostate tumors)
While the therapy - according to existing evidence - isn't necessarily "better" than traditional radiation treatments, the proponents (which include now the top ten cancer treatment centers) insist it can reduce many harmful side effects, especially for localized cancers. As the WSJ noted:
"The benefits are undisputed for rare pediatric brain cancers, adult eye tumors and cancers at the base of the skull."
But for prostate cancer the jury is still out, and certainly the benefits of the radiation treatment I received have to be considered at least as good and much more cost effective. (I was in the treatment center for one day, and received one high dose of 1930 cGy via Iridium 192 needles introduced in situ, see e.g.
While the advocates for proton beam therapy brag of its accuracy - assuming it's done in the right hands- my own therapy relied on a specialized inverse planning, or "IPSA" software, see e.g.
For which testing of the algorithm at multiple sites disclosed automatic protection for critical organs achieved by generating contour solutions that cleared a 3D "tunnel" around the urethra and rectum (for example) to spare them from the maximum delivered dose.
The worst side effects for me were in the immediate three or four month aftermath and included frequent urge to urinate and some burning upon urination. Also burning accompanying sexual activity. (Only a bit later I learned I could control the burning effects by taking one cranberry sofgel a day)
Medicare covered almost 95% of the total treatment costs, which - if I'd had Paul Ryan's stingy "premium support" (voucher) plan - would have likely bankrupted us - given it would only cover $10k or so a year.
It should also be known, as the WSJ notes, that Medicare also covers proton beam therapy "at about $1,100 per treatment session" . Nonetheless,
"several major insurers stopped after a 2012 study found it has no long term added benefit. "
Originally, as the WSJ notes, men with prostate cancer had made up 70 percent of patients at some proton centers, and that is now 50 percent.
Meanwhile, the manufacturers themselves are designing more compact machines as opposed to the Hitachi machine - nearly the length of two thirds of a football field. But smaller is no guarantee of success and as the Journal piece pointed out, ProTom International Inc. - maker of compact systems- already had to file for bankruptcy protection.
My advice to anyone considering this option is to look into it carefully, also consider that a simpler, less complex system might actually be better for your cancer treatment needs!