Significant Variation in Use of Single-Fraction Radiation Therapy for Palliation of Bone Metastases
Standardizing prescribing practices for single-fraction radiation therapy for palliation of bone metastases could lead to cost savings and improvement in patients’ quality of life, according to a study published in the August issue of the International Journal of Radiation Oncology • Biology • Physics.
Bone metastases are a common manifestation of distant spread of disease, occurring most frequently with prostate, breast, and lung cancers. Of these patients, two-thirds develop bone metastases to the spine, pelvis, or extremities. Radiation therapy is an effective form of palliative treatment for bone metastases. More than 25 randomized controlled trials have demonstrated that single-fraction radiation therapy provides the same amount of pain control as multiple-fraction radiation therapy; however, there is low use of single-fraction radiation therapy for bone metastases internationally.
Study Details
The study by Olson et al was designed to determine the use of single-fraction radiation therapy in British Columbia, a publicly funded health-care system where there is no financial incentive for extended fractionation and all radiation therapy is provided by the BC Cancer Agency with no direct cost to patients.
Patients who received palliative radiation therapy for bone metastases, regardless of the primary cancer site at diagnosis, from 2007 to 2011 were identified using the BC Cancer Agency’s Cancer Agency Information System (CAIS). During the study period, 8,601 patients received 16,898 courses of radiation therapy. Patients who received reirradiation for bone metastases were included, and patients who received more than one course of radiation therapy were considered independently for each course. Radiation therapy fractionation was divided into two categories: single-fraction radiation therapy or multiple-fraction radiation therapy. The most common primary disease site was breast (23.4%), and the most frequently treated bony metastatic site was the spine (42.2%).
Single-fraction radiation therapy was used to treat bone metastases in 49.2% (7,097) of the radiation therapy courses. Single-fraction radiation therapy was most commonly used to treat bone metastases that originated from hematologic (56.6%) and prostate (56.1%) cancers; the most common bony metastatic sites treated with single-fraction radiation therapy were the ribs (83%) and extremity (66.4%).
Wide Variation in Use of Single-Fraction Courses
There was a significant variation in the use of single-fraction radiation therapy by each of the five cancer centers operated by the BC Cancer Agency during the time of the study, with a range of 25.5% to 73.4% (P < .001). The study found that the overall utilization rate of single-fraction radiation therapy in British Columbia is 49.2%, a rate consistent with other Canadian and European data that show use ranges from 32% to 64%. Single-fraction radiation therapy use is much higher, however, than in the United States, where use ranges from only 3% to 13%
“Previous research has shown that single-fraction radiation therapy is equally as effective as longer multiple-fraction courses. Single-fraction radiation therapy offers greater convenience for patients, is associated with fewer side effects and incurs a lower cost. Even a modest change in the frequency of single-fraction radiation therapy use, in Canada and America, could lead to meaningful cost-savings, improved patient convenience, and reduced patient side effects, thereby increasing patients’ quality of life,” said Robert A. Olson, MD, MSc, lead author of the study, the research and clinical trials lead, and a radiation oncologist at the BC Cancer Agency Centre for the North.
“As a result of discussing our study outcomes among radiation oncologists in British Columbia, we have already seen an increase in the use of single-fraction radiation therapy for bone metastases. We are hopeful that these results will motivate practice change worldwide,” he noted.
Dr. Olson is the corresponding author for the International Journal of Radiation Oncologyy • Biology • Physics.
The study authors reported no potential conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
