The American Society for Radiation Oncology (ASTRO) outlined recommendations on best practices for treating patients with symptomatic bone metastases and strategies to improve their quality of life, according to updated clinical guidelines published by Alcorn et al in Practical Radiation Oncology.
Background
Many cancer types are capable of metastasizing to the bone and causing complications such as pain, broken bones, and spinal cord compression. Current treatments may provide symptom relief, prevent fractures, and control further growth of metastatic bone disease. Decades of research has demonstrated that external-beam radiation therapy may effectively manage symptomatic bone metastases. Since ASTRO last updated its clinical guidelines in 2017, several large trials have uncovered the benefits of advanced radiation techniques—intensity-modulated radiation therapy and stereotactic body radiation therapy—administering a highly targeted, escalated radiation dose in certain patients with bone or spine lesions.
“Radiation therapy is a cornerstone of care [in] patients with symptomatic bone metastases, offering a nonsurgical option for fast pain relief and improved quality of life with minimal side effects,” explained senior study author Tracy Balboni, MD, MPH, Professor and Clinical Director of Skeletal (Bone/Spine) Radiation Oncology at Harvard Medical School and Dana-Farber/Brigham and Women’s Cancer Center as well as Chair of the guideline task force. “Our guideline delineates several evidence-based approaches to deliver this tried-and-true therapy, including meaningful improvement from a single treatment session,” she continued.
Study Methods and Results
In a systematic review, a multidisciplinary guideline task force comprised of radiation, medical, and surgical oncologists; palliative care specialists; and a patient representative analyzed data from previous trials published through January 2023 as well as Radiation Therapy Oncology Group 0631 trial results published in April 2023 in order to inform the clinical guideline update.
The task force provided new evidence on best practices for delivering radiation therapy to unirradiated tumors and in the reirradiation setting. Among the updated guidelines were:
- Radiation therapy was strongly recommended to manage pain and other symptoms of bone or spine metastases, including those causing compression of the spinal cord or cauda equina.
- Surgery and dexamethasone combined with radiation therapy were recommended over radiation therapy alone in patients with spine metastases causing spinal cord or cauda equina compression. Postoperative radiation therapy was recommended in patients with nonspine bone metastases requiring surgery.
- Four previously recommended dosing schedules for conventional radiation therapy in patients with previously unirradiated nonspine bone metastases should be observed: a single fraction of 800 cGy, 2,000 cGy in five fractions, 2,400 cGy in six fractions, or 3,000 cGy in 10 fractions. Research indicated that patients may achieve similar pain relief and experience minimal side effects with each of these approaches. Although retreatment is more common following single-fraction radiation therapy, the convenience of this treatment option may make it the optimal choice in many patients such as those with limited life expectancy. The task force also introduced dosing schedules in patients with spinal cord or cauda equina cord compression who were ineligible for surgery as well as for reirradiation of bone and spine metastases.
- Stereotactic body radiation therapy was conditionally recommended over conventional palliative radiation therapy in patients with good performance status who don’t require surgery or display neurologic symptoms. Recommended dose constraints and fractionation regimens for stereotactic body radiation therapy were detailed.
Conclusions
The task force hopes its updated clinical guidelines may be used as a tool to promote appropriately individualized, shared decision-making between physicians and patients. None of the recommendations were intended to be construed as strict or superseding the appropriately informed and considered judgments of individual physicians and patients.
“The use of conformal radiation and dose escalation for symptomatic bone metastases has moved from the experimental domain toward routine clinical care for many patients,” emphasized lead study author Sara Alcorn, MD, PhD, MPH, Associate Professor and Vice Chair of Clinical Strategy in the Department of Radiation Oncology at the University of Minnesota Medical Center as well as Vice Chair of the guideline task force. “As advanced radiation technologies become more widely accepted, we can increasingly help more patients in fewer treatment sessions and retreat more patients whose bone metastases return,” she concluded.
Disclosure: The research in this study was funded by the Patient-Centered Outcomes Research Institute. For full disclosures of the guideline authors, visit practicalradonc.org.
