The number of radiation therapy facilities in the United States has grown by 17% over the last 15 years, according to a new study presented today at the American Society for Radiation Oncology (ASTRO) Annual Meeting. This growth has disproportionately favored urban areas already dense in treatment centers, however; roughly 5% of the U.S. population remains more than 50 miles from the closest facility.
“Radiation therapy is one of the primary treatments for cancer, but one in 20 Americans lives quite far from a radiation therapy clinic,” said lead author Sean Maroongroge, MD, MBA, a radiation oncology resident at The University of Texas MD Anderson Cancer Center in Houston. "If we do not incentivize or find ways to help people who live farther from treatment sites get access to radiation therapy, then this gap may continue to widen over time."
Between half and two thirds of people diagnosed with cancer receive radiation therapy, and the treatment is unique in that it generally is administered over multiple sessions that can require daily trips for several weeks. "With the growth of telemedicine, especially during the COVID-19 pandemic, there are a lot of ways we can think about transforming care, but radiation therapy delivery requires patients to come to a treatment facility," said Dr. Maroongroge.
Nonclinical factors like geographic access affect clinical care. Longer travel times for cancer treatment can negatively impact patients' clinical outcomes, quality of life and likelihood of finishing treatment without interruption. People who live far from a radiation therapy facility are substantially less likely to receive radiation, and this can lead to unnecessarily aggressive treatment plans, such as a patient with early-stage breast cancer receiving mastectomy when breast-conserving surgery with radiation is an established standard of care.
For the current study, researchers used data from state regulatory agencies, such as health departments, and national dosimetry monitoring organizations to update a database of radiation therapy clinic locations originally developed in 2005 by senior author Leslie K. Ballas, MD. Facilities that were active between 2018 and 2020 were mapped using a web-based program and compared with those in the original database.
Researchers found notable growth in the number of radiation therapy facilities over time, up 17% from 1,987 sites in 2005 to 2,332 sites in 2020. They estimated that roughly 70% of the U.S. population lives within 12.5 miles of a treatment facility.
"The growth in the number of facilities is not surprising, from a medical perspective. As patients and other physicians increasingly appreciate the value of radiation, we expect to see more centers built and more existing centers include radiation therapy as part of a comprehensive care paradigm," said Dr. Maroongroge.
The rate of growth increased faster for people closest to facilities (within 12.5 miles, from 65.4 to 69.6%) than it did for those farther away (within 50 miles, from 94.6 to 95.5%), however. Researchers estimated that 4.5% of the population lives more than 50 miles from the closest radiation therapy facility.
"The disproportionate growth suggests that new sites are being built closer to people who are already close, rather than closer to people who are farther away. It could be that those are the people who need access the most, and we need to think carefully about how to help these patients get access to care," said Dr. Maroongroge.
"The most unfortunate cases I see are when nonclinical factors undermine the type of care patients receive," he continued. "I have patients who just say that it's just not feasible for them to get radiation if they have to travel a long distance. The financial stress and the weight of logistical burdens can't be understated in terms of how much they dominate patients' lives."
While reasons behind the trends were beyond the scope of current study, other research has pointed to substantial overhead costs and changing provider preference as two potential factors in disproportionate growth. The heavy capital investment needed to build and maintain radiation therapy facilities, for example, could favor geographic areas with larger patient populations. Additionally, the most recent study of the radiation oncology workforce noted physicians are "gravitating toward urban and suburban locations at the expense of rural locations," and a separate study found that recent graduates entering the field strongly preferred working in large cities.
Next steps for the researchers include validating their results with additional datasets to better understand the populations who are at risk and identify potential levers to create change. Access for people who live close to facilities is also an area of interest. Even within cities, shortfalls in radiation therapy referrals and barriers such as reliance on public transportation can negatively impact the likelihood of patients receiving or completing treatment. A case study of breast cancer care in Atlanta, for example, found the median travel time to a radiation therapy facility on public transportation was seven times longer than it was with a private vehicle.
"There are a lot of questions in terms of policy and perhaps even technology that may help us deliver better care to underserved patients," said Dr. Maroongroge.
Attribution to the American Society for Radiation Oncology (ASTRO) Annual Meeting requested in all coverage. This release includes updated study information from the author(s).
- Abstract 203: Geographic access to radiation therapy in the United States
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The American Society for Radiation Oncology (ASTRO) is the largest radiation oncology society in the world, with nearly 10,000 members who are physicians, nurses, biologists, physicists, radiation therapists, dosimetrists and other health care professionals who specialize in treating patients with radiation therapies. For information on radiation therapy, visit RTAnswers.org. To learn more about ASTRO, visit our website or media center, and follow us on social media.
More information on radiation therapy from RT Answers, ASTRO’s patient education site: