Proton Therapy: A Path to Improved Outcomes and Quality of Life

OncologyLive, Vol. 20/No. 10, Volume 20, Issue 10

Although development outlays with proton therapy have decreased, treatment costs remain higher than for conventional radiotherapy, fueling a debate about whether the benefits justify the costs.

Andrew K. Lee, MD, MPH

Proton therapy is one of the most technologically advanced radiation modalities available today. Its unique ability to spare healthy tissue while delivering curative radiation doses to tumors results in fewer adverse events (AEs) and better quality of life for patients. Used in the United States for decades, proton therapy is now available at 29 centers across the country, making this promising treatment available to many more patients than just a few years ago. According to the 2018 Annual Survey of The National Association for Proton Therapy, the number of patients treated in 2016 was 70% higher than in 2012, the first year of the survey,1 and the 2018 total was still around 15,000 patients, according to a professor of radiation oncology at Massachusetts General Hospital.2

Despite this growth, proton therapy remains controversial. How the therapy is perceived has a lot to do with this. Historically, the cost for developing a proton center reached $200 million.3 Today, due to smaller economic footprints, technological advances, and vendor competition, facilities cost much less, ranging from $20 million to $150 million, depending on the number of treatment rooms.4 Although development outlays have decreased, treatment costs remain higher than for conventional radiotherapy, fueling a debate about whether the benefits justify the costs.

A Closer Look at the Controversy

Critics contend proton therapy unnecessarily increases treatment costs and the evidence base for its use remains unclear.4 However, the results of several credible clinical studies demonstrate real benefits to patients in many cancers. Studies cited by critics largely depend on claims-based data from which investigators made inferences regarding outcomes and toxicities. Although useful at times, claims-based data do not always reflect what actually happens to the patient clinically and should not be used for clinical decision making.

Looking closer at the cost issue, the total national expenditure for proton therapy is actually quite small compared with the cost of some drug therapies in cancer. In that regard, there is a failure to recognize the potential benefits relative to the overall cost of caring for patients over the course of their lives. Managing toxicities, whether short or long term, is expensive and can have financial ramifications not only for the patient, but also for payers, caregivers, and employers.

Additionally, some of the controversy is driven by competition. Whether in an academic setting or private practice, people and institutions tend to promote what they offer. If one center has proton therapy and the other does not, the nonproton center may be critical of the therapy simply because there is a fear of losing patients. Interestingly, some of the most vocal critics of proton therapy in the past who now have the technology in their facilities have become ardent supporters. This is not unusual, as the same thing happened with intensity-modulated radiation therapy 20 years ago.

Balancing Costs With Benefits

Determining whether the cost of proton treatment is fairly aligned with the benefits delivered depends, in large part, on which stakeholder perspective is being examined. Obviously, payers want to mitigate costs, which is understandable. Providers, for the most part, want what is best for their patients and to offer optimal outcomes, not only in terms of cancer control but also regarding toxicities. Patients want to be cured, but they also want the chance to enjoy their survival. Proton therapy provides the opportunity to optimize results, not only in terms of controlling the cancer but also by reducing AEs and improving quality of life. However, to have those incremental benefits, more economic resources may be required. This is true not only in radiation oncology, but in every aspect of healthcare.

One possible solution to obtain a better return on investment might involve changing the payment schedule for providers. Proton therapy requires a high level of technology and expertise, but there is a return, not only in terms of an increased cure fraction when a higher dose of radiation is delivered more accurately, but also in terms of reduced costs for managing short- and long-term toxicities.

On the bright side, costs are lower today for developing proton centers, having declined more than 50% over the last decade depending on the manufacturer. More single room centers are being built and will likely outnumber multiroom facilities within the next decade. Although single room centers are less expensive and may not have the functionality of larger treatment units, they do give more health systems access to this important technology.

Look at the Bigger Picture

Proton facilities are still costly to build, and treatments are more expensive than traditional radiotherapy; however, it is time to look beyond the immediate costs and short-term results when determining what this therapy brings to healthcare. Proton therapy should be viewed for what it is: an investment in improving outcomes and long-term quality of life for patients. At some point, we need to differentiate costs versus value when it comes to this technology. We all agree cost control is important. At the same time, if an incremental cost provides value to a patient, the value needs to be measured over the lifetime of the patient and not just during active treatment or for a few short months into survivorship. The reality of cancer care is that no matter what we do, sometimes the ramifications of treatment stay with the patient for months or years, impacting quality of life and increasing costs for managing toxicities.

As advancements continue to occur in all areas of medicine, the quality and length of life for our patients will continue to improve. Patients with cancer in their mid-60s may have another 20 to 30 years of life expectancy beyond treatment. Consequently, we need to think about what that means, not only in terms of cure, but also in dealing with the long-term AEs and the cost of managing them.

A recent study of cancer survivors found that 8%, or 1 in 12 of adults with the most common cancers, eventually develop a second malignancy unrelated to the first.5 The study also determined second cancers were often lethal, as 55% died of their second cancer and only 13% died from their first malignancy.5 The implications of these findings are important, because there is a limit to the amount of treatment patients can tolerate during their lifetime. When focusing on a patient’s first cancer, physicians may not always be considering the lifelong therapeutic tolerance of that patient, a factor that becomes critical if a second cancer develops. Proton therapy provides a way to not only control the initial cancer, but also minimize the toxicities of primary treatment, providing an opportunity to more effectively treat a second cancer if necessary. This is a good example of the value added by proton therapy that is difficult to measure and cannot be calculated in the short term.

The growing number of cancer survivors the United States will be dealing with over the next 5 to 10 years is another important consideration. While we celebrate the wonderful advancements that are curing more people than ever before, we need to be mindful of the sheer volume of these patients and the potential AEs and costs of these on a larger scale. With the number of cancer survivors growing at a rapid pace, it is important to try to minimize the impact of the treatment and still have good cancer control outcomes. Proton therapy is just one of many mechanisms that can help accomplish that goal.


  1. Annual survey shows surge in cancer patients treated with proton therapy & in number of indications [press release]. Scottsdale, AZ: The National Association for Proton Therapy; March 26, 2018. DRAFT-Annual-Survey-Press-Release-0320118a.pdf. Accessed May 1, 2019.
  2. Kim M. U.S. proton therapy: boom or bust? Bioengineering Today website. or-bust. Published August 3, 2018. Accessed May 1, 2019.
  3. Lagasse J. As proton therapy becomes cheaper, more hospitals look to add centers. Healthcare Finance website. healthcarefinancenews. com/news/proton-therapy-tech-become-cheaper-morehospitals- look-add-centers. Published April 25, 2016. Accessed May 1, 2019.
  4. Furlow B. Cost vs benefits: the controversy over proton beam radiotherapy. Oncology Nurse Advisor website. oncologynurseadvisor. com/home/cancer-types/general-oncology/cost-vs-benefits- the-controversy-over-proton-beam-radiotherapy/. Published February 28, 2018. Accessed May 1, 2019.
  5. Mulcahy N. 1 in 12 chance of second cancer in many survivors. Medscape website. Published July 21, 2016. Accessed May 1, 2019.