Background: Postoperative stereotactic body radiotherapy (pSBRT) is an emerging indication for spinal metastases (SM).
Objective: To report our experience with pSBRT for SM.
Methods: A retrospective chart review was performed for prospectively collected data of patients treated between September 2008 to December 2015 with pSBRT and followed with serial spinal MRIs every 2 to 3 mo until death or last follow-up. Univariate and multivariable analyses were performed to identify predictive factors.
Results: A total of 83 spinal segments in 47 patients treated with a median dose of 24 Gy in 2 fractions were included, with mostly lung and breast primaries. A total of 59.3% had preoperative high-grade epidural disease (ED) and 39.7% were unstable. The 12-mo cumulative incidence of local failure was 17% for all segments, and 33.3%, 21.8%, and 0% in segments with postoperative high-grade, low-grade, and no ED, respectively. Downgrading preoperative ED was predictive of better local control (P = .03). The grade of postoperative ED was also predictive for local control (P < .0001), as was a longer interval between prior radiotherapy and pSBRT in those previously irradiated (P = .004). The 12-mo overall survival rate was 55%. One case of radiculopathy, 3 vertebral compression fractures, and no cases of myelopathy, hardware failure, or skin breakdown were observed.
Conclusion: pSBRT is an effective and safe treatment. The association between downgrading preoperative ED and better local control following pSBRT is confirmed and supports the concept of separation surgery.
Keywords: Postoperative; Separation surgery; Spinal metastasis; Stereotactic body radiotherapy.
Copyright © 2019 by the Congress of Neurological Surgeons.