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Wise Buy? Proton Beam Therapy

— It helps only a few, and at a wildly extravagant cost

MedpageToday

On Feb. 18, 2014, Scripps Health in San Diego issued a press release that "celebrated the opening of the Scripps Proton Therapy Center," a $220 million facility to bring to southern Californians "one of the most advanced, accurate treatments available for cancer care."

It sounded like a weapon out of "Guardians of the Galaxy": A 95-ton superconducting cyclotron would use hydrogen and oxygen to create a plasma stream. Protons would be extracted from the plasma and accelerated to a speed of 100,000 miles per second. A beam-transport system would direct the proton stream to different treatment rooms, blasting tumors of the prostate, head and neck, breast, spine, lung and gastrointestinal tract, and many childhood cancers.

For those less intrigued by the technical details, the release touted the center's "modular stone walls and wood and tile design accents" intended to "provide a comforting, emotionally supportive environment for healing." Proton therapy, you might reasonably conclude, was the best thing to hit San Diego since sunshine.

Scripps and its two affiliates in the project -- Rady Children's Hospital and the University of California San Diego Health System -- said they could care for up to 2,400 patients annually.

Just after the center's three-year anniversary, however, the sunny skies turned gloomy. The Scripps Proton Therapy Center filed for bankruptcy protection.

Whatever effect plasmas and protein beams might have on cancer, they were evidently not having the hoped-for effect on patients. Court documents said that since the center's opening, it "has not operated on a profitable or even a break-even basis."

The Scripps center's failure to attract patients mirrors a national trend. At the 2016 annual meeting of the American Society for Radiation Oncology (ASTRO), researchers reported that the use of proton therapy was growing, but barely. In 2012, 5,377 patients were treated. That rose to just over 7,000 in 2015. The number of cases of prostate cancer, the most commonly treated condition, was nearly unchanged at about 2,300 cases annually. (The figures are from survey data collected by the National Association for Proton Therapy.)

Those numbers are troubling, but the financial figures are worse. During the period in question here, 2012 to 2015, the number of proton treatment centers doubled. That means the number of prostate cancer patients seen per center is dropping -- not a good thing when trying to cover a $220-million investment.

Market Struggles

And the financial woes extend beyond San Diego. A proton therapy center at Indiana University has closed. Another in Georgia is struggling. This is a tough economic lesson that seems lost in Oklahoma City, where there are two proton therapy centers 17 miles apart, making it even more difficult to attract enough patients to survive.

This bleak economic landscape might look a little bit brighter if researchers could say with confidence that proton beam therapy has clear advantages over conventional radiology. If that is the case, then the centers that survive this downturn might one day pay for themselves.

Unfortunately for proton beam therapy's purveyors and enthusiasts, there is little evidence of its superiority.

The most promising area for the use of proton therapy was once in prostate cancer, where radiotherapy often causes rectal complications, said Joel Greenberger, MD, professor and chair of radiation oncology at the University of Pittsburgh School of Medicine.

But the possible utility of proton therapy in prostate cancer is being undermined by two other developments. One is the realization that many cases of prostate cancer are best left alone and watched, without any treatment. "Ninety-five% of men with prostate cancer do not die of prostate cancer," Greenberger said. The other is that proton therapy is, in most cases, no more effective than conventional radiation treatments -- and it's far more expensive.

Dwight Heron, MD, chairman of radiation oncology at UPMC Shadyside in Pittsburgh, said that for those men who do need radiotherapy, "we can do it just as well" with conventional treatment. Proton therapy "does play a role, but we don't have the clinical evidence yet to support the use of protons for the range of cancers we usually treat -- and certainly not at the current cost." There are no randomized studies that prove protons are better than conventional treatment, he said.

Proton therapy costs range from about $30,000 to $120,000. In contrast, a course of treatment with radiosurgery costs about $8,000-$12,000, Heron said. IMRT (intensity-modulated radiation therapy) costs about $15,000. A radiation treatment center with stereotactic capabilities costs about $7 million to build, versus roughly $200 million for a proton therapy center, according to Heron.

Unique Capability

One area in which proton therapy might be uniquely valuable is in the treatment of pediatric cancers, Heron said. "Kids are so much more vulnerable, and they have a higher risk of developing other cancers due to the radiation."

Jatinder R. Palta, PhD, the chair of medical physics at Virginia Commonwealth University and chief physicist for the Department of Veterans Affairs' national radiation oncology program, is a strong proponent of proton therapy, but only for a small, select group of patients.

In a study he conducted for the VA, he said, "Our analysis did not find any class-one [statistically proven] evidence for proton therapy for main cancers like prostate, lung , or any other cancers," he said. But there were some exceptions. Some patients present in a way that makes proton therapy "unequivocally better than conventional therapy in terms of morbidity and outcomes."

These cases make up 5%-7% of patients, and it's not the site of their cancer that makes them good candidates for proton therapy -- it's the way the cancer presents. "If you have a patient you have treated, and the cancer has recurred, let's say, in the skull, you have a lot of normal tissue which has been irradiated before. Proton therapy can spare a lot of the normal tissue." This kind of situation could arise at other sites, too, he said.

These take advantage of a particular characteristic of proton therapy. X-rays deliver a dose of radiation to normal tissue as they exit the body after passing through a tumor. Protons can be managed to hit the tumor and more-or-less stop dead right there -- meaning there is little risk of an exit dose.

Palta also underscored the value of proton therapy in treating pediatric cancers. "When you have a young patient with a growing body and you radiate those normal structures, the growth is stunted. They will not grow at the same rate. Radiation retards the growth of the normal tissue," he said.

Keeping $$ at Home

But Palta has a far more disturbing explanation for the economic difficulties facing proton therapy centers. To explain his view, he does a quick bit of arithmetic. "We are treating about 1 million patients with radiotherapy," he said. "Let's say 5% of those patients are going to benefit from protons." That's 50,000 people.

If proton treatment centers each treated 500 patients per year, there should be enough patients to support 100 centers across the country. (That's 50,000 divided by 500, if you're keeping score.) Why, then, are so many of them facing such harsh economic realities?

One reason is that insurers are not covering most proton therapy. But the other explanation is the disturbing one: Radiation oncologists don't want to give away their income-producing patients.

"No provider is willing to give up patients, even though they know the long-term toxicity and morbidity of the patient they are treating with conventional therapy is bound to be higher," Palta said.

Did he really mean that oncologists would knowingly give patients sub-optimal treatment for financial reasons? Absolutely, he said. And they're unlikely to be exposed, because "they can always claim that they don't know."

He said he's seen it happen. Before moving to Virginia, Palta was at the University of Florida. "We had a proton facility at Jacksonville and a main campus in Gainesville. Our radiation oncologists in Gainesville would not send patients to Jacksonville. They would make the excuse that 'there's no evidence that protons are better. So why put the patients through a 70-mile drive [to Jacksonville]?'" This was not a question of competing institutions fighting for healthcare dollars. It was a civil war: both the Gainesville and Jacksonville facilities are part of the University of Florida.

Bottom Line

With this background, it's fair to ask: Is proton therapy a wise buy?

No, said Greenberger flatly. "Until we have some incontrovertible evidence that protons for certain things are better, no."

Heron agreed. "It could bankrupt the healthcare system even more quickly."

Palta also agreed. He noted that yet another proton center, in Hampton, Va., 80 miles down the road from him, was also having financial problems. "They don't have the patients."

Could this change as researchers continue to study proton therapy? "That's highly unlikely," Palta said. "The physics is simple. We know which cases will make a difference."

The only solution, he said, is to treat all of those who can benefit from proton therapy -- and only those who can benefit.

"It's personalized medicine," he said. At $220 million a pop.