Sarcomas metastasizing to the spine are a rare entity. Ideally an En-bloc resection is necessary to achieve durable local control (LC) rates. However, anatomical constraints often limit the degree of tumor resection. Because of this, other therapeutic modalities either replacing or as an adjuvant to resection are necessary. Stereotactic radiosurgery (SRS) is a reasonable candidate therapy. We conducted a systematic review of the literature using the following databases: PubMed, Science Direct, and Cochrane library. We used a combination of the following terms connected by boolean operators: "Metastatic Sarcoma, Sarcoma of the Spine, Spine Sarcoma, Metastasis, stereotactic radiosurgery, SRS." All retrospective and prospective cohorts, as well as randomized control trials reporting on patients with histopathologically confirmed metastatic sarcomas of the bony elements of the vertebrae, thecal sac, cord, or associated soft tissues of the spine were included. We excluded animal studies, case reports, case series, patients < 18 (pediatric cohorts), review articles and meta-analyses. No date filters were applied to our search. Our final analysis included 5 studies ranging from 2009 to 2024 reporting on 260 patients and 371 associated lesions. Leiomyosarcoma was the most frequently reported histologic subtype (60%). Most lesions were localized to the thoracic spine (48.6%). 75% of studies reported a median dose < 30Gy, and achieved biologically equivalent doses (BEDs) ranging from < 50-100. Pooled 1-year median survival was 64.5% (IQR: 61.8-75.10). Pooled 1-year median LC was 86% (IQR: 79.4-88.5). Three of five studies (60%) for OS and 4/5 (80%) for LC had data availability suitable for meta-analysis. The 1-year OS and LC rates proportions across these studies were 67% (proportion = 0.67, 95% CI: 0.57-0.75, p = 0.07, I2 = 63%), and 84% (proportion = 0.84, 95% CI: 0.78-0.89, p = 0.10, I2 = 52%) respectively. Median follow up across all studies was 18 months (IQR:12.7-31.3). SRS is a reasonable alternative therapy in either the up front, salvage or adjuvant setting which can facilitate durable LC.
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