Treatment of ambulatory patients with metastatic epidural spinal cord compression: a systematic review and meta-analysis

OBJECTIVE Approximately 10% of patients with spinal metastases develop metastatic epidural spinal cord compression (MESCC), which left undiagnosed and untreated can lead to the loss of ambulation. Timely diagnosis and efficient multidisciplinary treatment are critically important to optimize neurological outcomes. This meta-analysis aimed to determine the most efficient treatment for ambulatory patients with MESCC. METHODS The authors conducted a systematic review and meta-analysis of the treatment of mobile patients with MESCC in terms of outcomes described as local control (LC), ambulatory function, quality of life (QOL), morbidity, and overall survival (OS). RESULTS Overall, 54 papers (4101 patients) were included. A trend toward improved LC with stereotactic body radiotherapy (SBRT) compared with conventional external beam radiotherapy (cEBRT) was demonstrated: random effects modeling 1-year LC rate 86% (95% CI 84%- 88%) versus 81% (95% CI 74%-86%) (p > 0.05), respectively, and common effects modeling 1-year LC rate 85% (95% CI 82%-87%) versus 76% (95% CI 74%-78%) (p < 0.05). Surgery followed by adjuvant radiotherapy, either cEBRT or SBRT, showed no significant benefit in either LC (OR 0.88, 95% CI 0.65-1.19) or ambulatory function (OR 1.51, 95% CI 0.83-2.74) compared with radiotherapy without surgery. There was a significant benefit of surgery compared with cEBRT regarding QOL, and furthermore SBRT alone provided long-term improvement in QOL. The type of treatment was not a significant predictor of OS, but fully ambulatory status was significantly associated with improved OS (HR 0.46-0.52, relative risk 1.79-2.3). Radiation-induced myelopathy is a rare complication of SBRT (2 patients [0.1%] in the included papers). The morbidity rate associated with surgery was relatively high, with a 10% wound complication rate and 1.6% hardware-failure rate. CONCLUSIONS SBRT is an extremely promising treatment modality being integrated into treatment algorithms and provides durable LC. In mobile patients with MESCC, surgery does not improve LC, survival, or ambulatory function; nonetheless, there is a significant benefit of surgery in terms of QOL. In patients with MESCC without neurological deficit, the role of surgery is still debatable as studies demonstrate good LC for patients who undergo SBRT without preceding surgery. However, surgery can provide safe margins for the administration of the ablative dose of SBRT to the entire tumor volume within the constraints of spinal cord tolerance. Further randomized controlled trials are needed on the benefit of surgery before SBRT in mobile patients with MESCC. With the excellent results of separation surgery and SBRT, the role of highly invasive vertebrectomy is diminishing given the complication rate and morbidity of these procedures.