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Proton Beam Radiation Therapy: Balancing Evidence-Based Use with the Bottom Line (Part 3 of a Multipart Investigation)

Rosenthal, Eric T.

doi: 10.1097/01.COT.0000372156.69184.ff


In the highly competitive world of high-tech cancer therapeutics there is a very exclusive and expensive club that currently has only seven members who are clinical providers of proton beam radiation therapy (PBRT).

The club costs an average of more than $150 million to join—for the facilities and real estate—and as noted in Parts 1 and 2 of this series (OT 3/25/10 and 4/10/10), in the articles by Daniel Keller, PBRT's therapeutic benefits for all cancers being treated have yet to be proven to be superior to other, less expensive and more readily available forms of radiation therapy.

The seven proton centers are regionally diverse—in California, Massachusetts, Florida, Oklahoma, Texas, Indiana, and Pennsylvania—but are not all necessarily regional centers, since competitive factors have served to hamper some referrals to neighboring facilities in certain areas of the country.

This situation of a limited number of high-cost centers offering exclusive treatments with little clinical data to prove efficacy seems to beg two questions:

  • Do the haves with PBRT tend to steer patients with certain tumor types toward this therapy to help recap the outlay of expenses?
  • And do the have-nots hesitate to make referrals to competitors' facilitates when PBRT might be beneficial and, if so, then what are the ethical implications?

OT sought to learn more about the state of usage of this state-of-art technology, finding some sources highly responsive and others resistive to discussing the matter.

Some of those who were reluctant to comment came from academic cancer centers without proton beam capability and some who did comment—on or off the record—often included some less-than-subtle snipes about proton beam applications at certain other institutions, referring to them as “prostate cancer factories.”

The National Association for Proton Therapy (NAPT) claims to be the “Voice of the Proton Community in the US” on its Web site ( The independent, not-for-profit, public benefit corporation was founded in 1990 by Loma Linda University Medical Center, the same year Loma Linda became the first hospital-based proton beam clinical center.

In an interview for this article, the association's Silver Spring, Md.-based Executive Director, Leonard Artz, spoke about the association and its member organizations. He said he was hired originally by Loma Linda but that he has been independent of any particular member institution for years.

Regarding statistics, he said that among all radiation therapy in the United States, proton therapy constitutes less than 1% of all total treatment and that photon—i.e., x-ray—therapy uses 20 million radiation fractions annually vs only 100,000 proton fractions.

Asked about the number of patients treated, he said that although the member institutions “are not always willing to share this kind of information, and none of them are operating at full capacity, they treat [in total] about 2,500 to 3,000 patients a year.”

He said there has been increased interest by institutions to join the association, but two years ago the Board decided to draw the line for membership inviting only those centers that were operating or had its finances in place and were under construction, and excluding those who had interest but had not as yet “poured concrete.”

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Currently Listed as Operating Centers

Today, the seven operating centers are:

  • James M. Slater, MD, Proton Treatment and Research Center at Loma Linda University Medical Center.
  • Francis H. Burr Proton Center at Massachusetts General Hospital.
  • Midwest Proton Radiotherapy Institute at Indiana University.
  • University of Florida Proton Therapy Institute.
  • University of Texas M. D. Anderson Cancer Center's Proton Center.
  • ProCure Proton Therapy Center, located at the INTEGRIS Cancer Campus in Oklahoma City.
  • Roberts Proton Therapy Center at the University of Pennsylvania Health System.

In addition, NAPT listed the following centers as under construction:

  • Hampton University Proton Therapy Institute in Virginia.
  • Northern Illinois University Proton Therapy Center.
  • CDH Proton Therapy Center, a ProCURE Center in Warrenville, Illinois.
  • In addition, the South Florida Proton Center is listed by the association as “under development.”

However, these lists are not quite as solid as the concrete that's been poured—Northern Illinois recently announced that its certificate of need had expired and that the project was being placed on hold, and the University of Miami's “deal had fallen through,” Mr. Artz said.

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Pay Off Debts

One of the concerns about building new facilities is the tremendous costs involved and the ability to pay off large debts in a reasonable period of time.

Sometimes the lure of high-tech exclusivity and its marketing implications can lead some institutions to covet the technology, and sometimes it's more of a matter of wanting to have the latest technology and put it through rigorous evidence-based testing to determine its best, most effective use.

And sometimes it may be necessary to compromise and use proton beam therapy to treat cancers that are more lucrative but have less scientific backing because large outlays of money need to be recouped.

Anthony L. Zietman, MBBS, MD, President of the American Society for Radiation Oncology is the Jenot and William Shipley Professor of Radiation Oncology at Harvard Medical School and Director of the Radiation Oncology Residency Program at Massachusetts General Hospital.

His specialty is prostate cancer, and his clinical research includes exploring the therapeutic gains possible from radiation dose escalation using conformal radiation therapy with the proton beam, and investigating combinations of external radiation and brachytherapy.

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‘Very Deeply Disturbing Aspect of Contemporary Medicine’

When we spoke last month, Dr. Zietman said his comments were his own, and did not necessarily reflect ASTRO's position on proton beam therapy.

“I believe during this last decade that technology has proceeded at an incredible pace, but that doesn't necessarily mean better patient care.

“We exist in a very competitive medical environment, and over the last 10 years technology has been a way hospitals brand themselves, the way they sell themselves with billboards on the highway announcing they have proton beam therapy or perhaps a Cyberknife.

“We should be masters of technology, but technology has become our master and an end in itself, and many of these technologies are being widely used I expect because they are prestige projects for marketing purposes without proof of real benefit. They may be beneficial, but no one has proven it in some cases, and this is really a very deeply disturbing aspect of contemporary medicine.”

Dr. Zietman said that proton beam therapy has great potential and that as someone who uses it, he is very impressed. The technique, he explained, is really only regular radiation, but fancier, and it doesn't necessarily improve upon other modalities used for certain cancers.

But for certain cancers, in pediatrics and certain brain and spinal tumors, proton beam “wins hands down,” and there's no way he would treat such patients with anything else because the distribution is far superior when there are critical structures nearby like spinal cords or eyeballs.

“With these sites, if you go wrong, then the patient is blind or paraplegic, and that's catastrophic. There's no doubt that America needs proton beam therapy, especially if you look at pediatric-based and skull-based populations, and if you add them all up, and base need on current evidence, then you would probably need between five and 10 geographically distributed centers. This is what is happening in Britain where [based on population and medical evidence] two centers are being proposed—in London and the north.”

Dr. Zietman acknowledged that he works in an enviable environment where proton beam therapy research originated, has been used clinically since 1961, and has been studied under a National Cancer Institute program project grant since 1972.

ANTHONY ZIETMAN, MD: “I'm personally not convinced that proton therapy is superior treatment for prostate cancer

ANTHONY ZIETMAN, MD: “I'm personally not convinced that proton therapy is superior treatment for prostate cancer

However, until 2001 patients would have to head over to Harvard University's physics laboratory to receive treatment until Mass General built its own hospital-based center with half its funding from the NCI, another advantage since the Boston center is one of the very few that is debt free.

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Therein Lies the Rub

And therein lies the rub, with the financing and therapeutic focus of other such facilities often pushing patients to prostate therapy using protons.

“Because we are have zero debt, we are free to practice however we like and we have our priorities with kids and brain tumors—specifically those that are skull based—being number one; followed by patients on protocols, primarily with lung and pancreatic cancers.”

He acknowledged that Mass General has been treating prostate cancer since 1979 but only on protocols, and had conducted randomized trials several decades back that showed that higher doses were better and could be given safely with protons. But since then, he added, other radiation treatments have been developed using Intensity Modulated Ration Therapy (IMRT) or seed implants that also deliver very high doses—meaning that the question still has to be answered about whether protons are better than regular radiation.

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Trial to Compare QOL with IMRT vs PBRT

To that end, Mass General and the University of Pennsylvania Cancer Center have submitted a $10 million grant for a randomized clinical trial comparing IMRT with proton therapy, with quality of life as the endpoint.

The trial will begin as soon as funding is in place, he said, and which modality will be used at each center will be determined by a coin toss.

“I'm personally not convinced that proton therapy is superior treatment for prostate cancer. It's not bad treatment, but we just don't know if it's better and won't know until we've done randomized clinical trials.”

A March 1, 2010 report in the Journal of Clinical Oncology coauthored by Dr. Zietman concluded that although the trial strongly validated the use of proton beam therapy, it was not designed to test whether proton therapy was more or less efficacious than other conformal techniques, or brachytherapy or surgery.

He also was senior author of a study published in the March 17 JAMA (first author is James A. Talcott, MD, SM), which found that among men with clinically localized prostate cancer, treatment with higher-dose combined proton and photon radiation compared with standard dose was not associated with an increase in patient-reported prostate cancer symptoms after a median of 9.4 years.

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Misimpression that PBRT Has No Side Effects

Many patients come to him with the misunderstanding that proton beam therapy has no side effects, Dr. Zietman noted: “They get this from marketing, and my first job is to disabuse them of all their misconceptions, and let them know that the side effects are not bad, but neither are they zero.”

He said that proton beam therapy is not new technology, but actually old technology that continues to evolve, and that when patients fly in from all over the world asking him about proton therapy for their prostate cancer they “fall off their chairs when they find out I don't advocate it.”

“Rather, I consider it a personal win if they come in wanting protons and go out on active surveillance, because then I know I've really done my job.”

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Controversies More about Use with Prostate Cancer than as Another Form of RT

The controversies over proton beam therapy may be more about its use with prostate cancer than about its use as another radiation modality, Dr. Zietman said, noting that almost no one was doing active surveillance until about four or five years ago.

“Surgeons are interested in treatment and radiation oncologists are interested in treatment because we are incentivized to treat and not to not treat.”

Children, who often require anesthesia, can take up to six times as long to treat with proton beams than a prostate cancer patient, and centers with more than $150 million in debt may be motivated to treat six men for prostate cancer rather than a single pediatric case, he explained.

“Some say that one way of looking at this would be that you need to treat the prostates to subsidize the machine needed to treat the kids and the skull-based tumors, and they consider prostate cancer patients as maintenance to enable them to deliver this unique therapy to the kids. I hate this argument, though, because it means we are happy to treat at great expense men who in many situations don't need any treatment. It's about as mixed-up a statement as you'll ever find.

“I'm afraid the prostate issue will cause proton therapy to be discredited and the baby will be thrown out with the bath water. We need proton beam therapy and we need centers that are advancing proton beam therapy, and to discredit the whole thing just because of prostate use is very worrisome.”

Dr. Zietman said that about two years ago there were perhaps 20 contracts ready to be signed for proton facilities in the United States, but that the financial meltdown and recession resulted in several of them evaporating and put the brake on what he called a number of reckless plans.

He said some facilities were looking to set up proton programs without any radiation oncologists or physicists on board, and that in addition to worrying about safety, he thinks some centers are selling an illusion that prostate cancer patients may be getting something superior.

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ASTRO Supports Use of PBRT

Dr. Zietman concluded with a comment as ASTRO's president: “ASTRO supports the use of proton therapy, because I really think it's a therapy we need. But we want to be selective and appropriate in using protons in situations that we know are beneficial, and want to do more clinical investigations into areas we have concerns or doubts. To me, that's a totally reasonable position.”

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Next Part

Coming up in the next installment of our series on proton beam radiation therapy: use at various centers; referral and non-referral patterns; not-for-profit academic centers and commercial centers; and future plans for large proton-beam facilities and smaller one-room units.

© 2010 Lippincott Williams & Wilkins, Inc.
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