Two new, large studies led by researchers at the American Cancer Society showed an increase in the use of proton-beam therapy for patients with cancer in the United States during the past decade. However, Black patients were less likely to receive proton-beam therapy than White patients, and the racial disparity increased over time. The studies were published by Leticia M. Nogueira, PhD, MPH, and colleagues in JAMA Network Open.
Leticia M. Nogueira, PhD, MPH
“We found that proton-beam therapy use increased nationally between 2004 and 2018 for all eligible cancers, especially for cancers for which proton-beam therapy is the recommended radiation treatment,” said Dr. Nogueira, Senior Principal Scientist, Health Services Research at the American Cancer Society and lead author of both studies. “Especially concerning, however, was that our findings also showed racial disparities increased as availability of proton-beam therapy increased in the United States.”
Proton-beam therapy is potentially superior to photon-based radiation therapy for tumors with complex anatomy, tumors surrounded by sensitive tissues, and childhood cancers. However, it can cost up to twice as much as traditional photon-based radiation therapy.
Study Details
For both studies, researchers used the National Cancer Database, a hospital-based cancer registry jointly sponsored by the American College of Surgeons and the American Cancer Society. This database includes over 1,500 facilities accredited by the Commission on Cancer and collects treatment information on over 70% of individuals diagnosed with cancer in the United States. To evaluate patterns of proton-beam therapy, data were analyzed using American Society for Radiation Oncology guidelines—which designate cancers for which proton-beam therapy is the recommended treatment modality and cancers for which proton-beam therapy is still being evaluated.
Newly Diagnosed Patients
Of nearly 6 million patients analyzed, the use of proton-beam therapy in the United States increased overall for patients with newly diagnosed cancers from 0.4% in 2004 to 1.2% in 2018. Private health insurance was the most common insurance type among patients for which proton-beam therapy was the recommended radiation treatment, while Medicare was the most common insurance type among patients treated with proton-beam therapy for cancers for which its efficacy is still under investigation.
Racial Disparity Uncovered
Researchers also found Black patients were less likely to be treated with proton-beam therapy than White patients (0.3% vs. 0.5%), especially for cancers for which proton-beam therapy is recommended over photon-based radiation therapy. Importantly, the racial disparity in receipt of proton-beam therapy increased as the number of facilities offering proton-beam therapy in the United States increased, and this disparity was not eliminated after additional matching on socioeconomic status or health insurance coverage type.
“Our findings, unfortunately, highlight the fact that Black patients continue to benefit less from advances in medicine like proton-beam therapy, even with increased availability of recommended treatment modalities,” added Dr. Nogueira. “Efforts other than increasing the number of facilities that provide proton-beam therapy will be needed to eliminate these disparities.”
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
