Is Proton Beam Therapy worth all the hype?
There is a National Association for Proton Therapy that “promotes education and public awareness of the clinical benefits of proton beam radiation therapy.” News articles within the past few years have shown patients lining up for treatment using the new technology and hospitals dealing with financial issues because of the cost of building a proton beam therapy center. The science behind the technology seems to be sound and the small amount of clinical research that has been conducted has yielded seemingly positive results. A US News Health section article from 2008 said, “Even with eight more of the expensive facilities planned, there will be nowhere near the number of centers needed to treat every patient who might benefit, proponents of the technology say.” An April 2012 article from Medical News Today described “Proton accelerators” used “ to treat cancer” “as the ’most costly medical devices” in the world.” The article went on to state that the United States and the UK are making significant investments to construct a number of these proton beam accelerator facilities.
There’s a fair amount of hype surrounding proton beam therapy…
But does it bring better outcomes?
To answer that question, let’s take a look at what the technology really does.
Unlike standard x-rays, protons can be programmed to release high energies at a pre-set distance. It is this high energy that is ultimately responsible for killing tumor cells. When standard radiation therapy is used to treat cancers, everything in the path of the x-ray beam is injured by that beam. When using protons, a lower amount of energy is released as the beam passes through normal tissues, and a high amount of energy is released once the beam is in the vicinity of the tumor target. This advantage of sparing normal tissues and being able to deliver higher energies to the tumor is the theoretical benefit of protons over standard radiation therapy.
Clinical trials for most cancers to date either have not been done, or have not shown that this theoretic advantage translates into better outcomes for patients.
This technology is not cheap and volume pays the bills. The service volume is not in pediatric cancers or orbital cancers, but in prostate cancer, a cancer that is diagnosed in over a quarter of a million men each year. Some believe that with the precision of proton beam therapy over other external beam radiation therapies, the likelihood of damaging other anatomical structures is lowered. However, there has not been a single randomized trial to prove that proton beam therapy is any better than conventional radiation therapy and many more believe that “watchful waiting” is the best technique.
In fact, there are concerns in using proton beam therapy for the treatment of prostate cancer. The prostate is located in the pelvic region and its position is susceptible to changes of bladder and rectal volume, therefore the chances of hitting the prostate are lowered and there is an increased risk of the protons delivering their energy to healthy tissue or organs.
Proton beam therapy is expensive and hasn’t been proven to be more effective than conventional treatment methods, but it is still a profitable business. Like many areas of health care, the philosophy of “build it and they will come” seems to work.
Physicians are willing to try the new technology and Medicare is paying for it. Will we continue to build it? The bigger question, will they continue to come?