Bone metastases are a common manifestation of distant relapse from many types of solid cancers, especially those arising in the lung, breast, and prostate. As many as 80 percent of patients with solid tumors will develop painful bone metastases to the spine, pelvis, and extremities during the course of their illness .
The goals of palliative treatment of bone metastases are pain relief, preservation of function, and maintenance of skeletal integrity. When bone pain is limited to a single or a limited number of sites, local field external beam radiation therapy (RT) to the painful sites can provide pain relief in approximately 60 to 85 percent of cases, with complete pain response reported in 15 to 58 percent . If symptomatic lesions are widespread, radiopharmaceuticals or hemibody radiation may provide useful palliative alternatives. Although treatment can be effective for patients with mild, moderate, or severe pain, early intervention may be useful in maintaining quality of life and minimizing side effects of analgesic medications .
The use of external beam and hemibody irradiation will be reviewed here. An overview of bone metastases is presented separately, as are other aspects of cancer pain management. (See "Overview of the epidemiology, clinical presentation, diagnosis, and management of adult patients with bone metastasis" and "Cancer pain management: General principles and risk management for patients receiving opioids".)
EXTERNAL BEAM RT
Guidelines from the American Society for Radiation Oncology (ASTRO) support treatment with a single fraction of radiation using a dose of 8 Gy to provide palliation for relief of pain from bone metastases.
Based upon a systematic review of the literature, this approach improved patient convenience and was more cost effective compared with fractionated schedules . The use of a single 8 Gy fraction for pain relief is also supported by a second systematic review of the literature that looked at different doses of radiation administered as a single fraction . That review also concluded that a dose of 8 Gy was more effective than lower doses in providing pain relief.