Stereotactic body radiotherapy (SBRT) was found to be superior to conventional external beam radiotherapy (EBRT) for pain control in patients with painful spinal metastases. These study results were recently published in Lancet Oncology.
The study was a prospective, open-label phase 2/3 trial (ClinicalTrials.gov Identifier: NCT02512965) conducted at centers throughout Canada and Australia. Patients with painful spinal metastases involving a maximum of 3 consecutive vertebral segments were randomly assigned to receive either SBRT dosed at 24 Gy in 2 daily fractions or to conventional EBRT dosed at 20 Gy in 5 daily fractions. The primary study endpoint was the proportion of patients, in intention-to-treat analysis, who experienced a complete response for pain related to the target site at 3 months after undergoing the study treatment.
The SBRT group included 114 patients, and the conventional EBRT group included 115 patients. The median study follow-up was 6.7 months. A complete response to pain at 3 months was demonstrated in 35% of patients in the SBRT group and in 14% of patients in the conventional EBRT group (risk ratio, 1.33; 95% CI, 1.14-1.55; P =.0002). In a multivariable analysis of this endpoint, the odds ratio was 3.47 (95% CI, 1.77-6.80; P =.0003).
Grade 3 pain was reported in 5% of patients in the SBRT group and in 4% of the conventional EBRT group. Any-grade vertebral compression fractures occurred in 11% of patients in the SBRT group and in 17% of patients in the conventional EBRT group. There were reportedly no treatment-related fatalities.
“The results of this trial suggest that stereotactic body radiotherapy at a dose of 24 Gy in two fractions is superior to conventional external beam radiotherapy at a dose of 20 Gy in five fractions in achieving complete pain relief at the radiation study target vertebral segment volume site,” the study investigators concluded in their report.
Disclosures: Some authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Sahgal A, Myrehaug SD, Siva S, et al. Stereotactic body radiotherapy versus conventional external beam radiotherapy in patients with painful spinal metastases: an open-label, multicentre, randomised, controlled, phase 2/3 trial. Lancet Oncol. 2021;22(7):1023-1033. doi:10.1016/S1470-2045(21)00196-0