Cost of radiation therapy among Medicare patients varied most widely because of factors unrelated to a patient or the patient’s cancer, reported researchers in the Journal of Oncology Practice (2015; doi:10.1200/JOP.2015.005694).

Year of diagnosis, location of treatment, clinic type, and individual radiation provider accounted for 44% to 61% of the variation in cost for patients with breast, lung, and prostate cancer therapies, according to the study. Factors associated with the patient or patient’s tumor accounted for less than 3% of the variation in the cost of radiation therapy.

“We found that variability in Medicare reimbursement for radiotherapy does not depend on individual characteristics of patients or their cancers,” said James Murphy, MD, assistant professor at University of California (UC) San Diego School of Medicine and radiation therapist at Moores Cancer Center at UC San Diego Health. “Rather, reimbursement was tied to the provider, geography, and technology used to treat patients. This strongly suggests inefficiency within the current Medicare reimbursement framework for radiation therapy.”

Up to two-thirds of patients with cancer receive radiation therapy. Researchers focused on breast, prostate, and lung cancers because they represent the most common malignancies treated with radiotherapy.

The cost of radiation therapy was estimated from Medicare reimbursements for outpatient radiation treatment. The total cost of radiation therapy for the 55,288 patients in the study was estimated to be more than $831 million.

“Understanding why costs vary for radiation therapy helps policy makers evaluate the efficiency of the current fee-for-service Medicare reimbursement system. Such insights are likely to shape policy reforms in the near future,” said Anthony Paravati, MD, first author of the study.

The authors acknowledge that the study does not consider the relationship between cost of radiotherapy and quality of care, therefore higher cost radiation could lead to higher quality radiation. The link between cost and quality of care represents a future research question the authors hope to answer.