Multifraction radiotherapy is standard to treat pain in patients with bone metastases that are mostly not in their spine, but new research has shown that single-fraction stereotactic body radiotherapy had higher rates of overall pain response and better local disease control.
Multifraction radiotherapy (MFRT) is standard to treat pain in patients with bone metastases that are mostly not in their spine, but new research has shown that single-fraction stereotactic body radiotherapy (SBRT) had higher rates of overall pain response and better local disease control.
The study, published in JAMA Oncology is the first randomized controlled trial to compare the 2 therapies, according to the authors. It was performed at a tertiary cancer center with 160 patients enrolled between September 19, 2014, and June 19, 2018. The patients were randomly assigned 1:1 to receive either single-fraction SBRT or MFRT.
“Bone is a common site of metastasis in advanced cancer, and bone metastases often result in debilitating cancer-related pain,” the authors explained. They added that since newer therapies have improved outcomes and increased survival for patients with metastatic disease, “providing durable pain control is important for preserving their quality of life.”
A total of 81 patients received SBRT and 79 patients received MFRT. There were 4 types of response possible: complete response (CR) with a pain score of 0 at the treated site and no increase in morphine-equivalent doses (MEDs); partial response (PR) with a reduction in pain score of 2 or more points above baseline with no increase in MED; pain progression (PP) with an increase in pain score of 2 or more points above baseline with no chance in MED or an increase in pain score of 1 point above baseline with an increase in MED of 25% or more; or indeterminate response (IR), which included all other responses.
The participants had follow-up visits at 1 to 3 months after treatment and then at 6, 9, and 12 months after treatment. After that, any follow-up visits were at the physician’s discretion. At 1 month 44% (n = 36) patients in the SBRT group and 30% (n = 24) of patients in the MFRT group had CR or PR. At 3 months the rates were 38% (n = 31) and 21% (n = 17), respectively.
The researchers also found that patients who received SBRT had higher local progression-free survival rates compared with patients who received MFRT at 1 year (100% vs 90.5%; P = .01) and at 2 years (100% vs 75.6%; P = .01). There was no difference in overall survival between the groups and the median survival was 6.7 months for both groups.
“These findings represent the first prospective randomized evidence to suggest that SBRT should be the standard of care for patients with excellent performance status, longer life expectancy, and limited bone metastases,” the authors concluded. “We recommend that higher single-fraction SBRT doses be further tested in larger phase 3 studies to validate our findings.”
Nguyen Q, Chun SG, Chow E, et al. Single-fraction stereotactic vs conventional multifraction radiotherapy for pain relief in patients with predominantly nonspine bone metastases: a randomized phase 2 trial [published online April 25, 2019]. JAMA Oncol. doi: 10.1001/jamaoncol.2019.0192.