Stereotactic Body Radiation Therapy in Nonsurgical Patients with Metastatic Spinal Disease and Epidural Compression: A Retrospective Review

BACKGROUND: In the setting of spinal metastases with epidural cord compression, radiosurgery is often only considered when there is sufficient separation between the epidural disease and the spinal cord. However, in patients who are nonsurgical candidates or those who prefer nonoperative management, there may be a benefit from stereotactic body radiation therapy, even when the epidural target is closer than the traditionally referenced 3 mm distance from the spinal cord. The purpose of this retrospective study is to evaluate our institution's experience in treating 20 such patients. METHODS: We reviewed records of all patients treated with stereotactic body radiation therapy for spinal metastases at our institution from January 2010 to January 2016, with follow-up through December 2016. The primary end point was local progression of disease. Local progression was defined as clear radiographic disease growth on follow- up imaging or worsening clinical symptoms in the absence of evidence for radiation myelopathy. RESULTS: Local control was obtained in 55% of patients meeting these criteria without a single case of radiation myelitis. Most patients with disease progression were able to undergo additional local treatment. CONCLUSIONS: Although local control was less than expected when compared with spine radiosurgery with adequate separation between the target and spinal cord, this treatment appears to be a viable option in the nonsurgical candidate.