In a finding likely to add fuel to the debate over treatments for prostate cancer, proton-beam therapy provided no long-term benefit over traditional radiation despite far higher costs, according to a study of 30,000 Medicare beneficiaries published Thursday in the Journal of the National Cancer Institute.
Proton radiotherapy uses atomic particles to treat cancer rather than X-rays and theoretically can target tumors more precisely. But it requires a particle accelerator roughly the size of a football field that typically costs about $180 million.
Faith in the superiority of proton therapy by some has sparked an arms race among major medical centers. Ten proton accelerators are in operation in the U.S., and nine more are in development, including two by the Mayo Clinic and one by Memorial Sloan-Kettering Cancer Center and a consortium of other hospitals in New York City.
Ion Beam Applications of Belgium is the leading manufacturer. Others include Hitachi Ltd., Varian Medical Systems Inc. and Mevion Medical Systems Inc.
Critics long have cited proton-beam therapy as a costly new technology with no proven advantage. Medicare pays over $32,000 per patient for proton therapy, compared with under $19,000 for radiation, according to the study.
Some 242,000 men in the U.S. are diagnosed with prostate cancer each year, and many oncologists and health-policy experts say the condition is over-treated.
Most prostate cancers are slow-growing, so many men could avoid treatment and ultimately die of something else, experts say. But about 28,000 U.S. men die annually from aggressive prostate cancers that aren't treated in time, so most men opt to treat their cancers as a precaution, either with radiation or surgery.
Side effects of both can include incontinence and impotence, so researchers have sought potentially less-damaging therapies.
Proton-beam therapy has been the subject of heated debate among urologists, radiation oncologists and health-care cost analysts. The therapy isn't considered more effective than standard radiation, or surgery, at stopping the cancer. And the patient experience is about the same as with standard radiation: Patients typically have daily treatments, Monday through Friday, for approximately eight weeks. Each treatment is painless, and lasts about five minutes.
The main debate has been over side effects.