Stereotactic Radiosurgery (SRS) for Primary Intradural Spinal Tumors: A Meta-analysis

Introduction: While primary intradural spinal tumors (PIST) are commonly treated with surgery, stereotactic radiosurgery (SRS) is typically considered when patients are poor surgical candidates or have recurrent or unresectable tumors. However, the use of SRS is controversial, and its efficacy remains relatively unclear. Our aim with this study is to investigate the therapeutic response among PISTs treated with SRS.

Methods: We performed a systematic literature search in the databases Medline, Embase (Ovid), Scopus, Web of Science Advance, and Cochrane Central from inception to 08/06/2024. We included studies that reported on SRS outcomes in patients with primary spinal tumors and meta-analyzed the proportions of recurrence and the extent to which local control (LC) was achieved. The quality of included studies was assessed using the ROBINS-I tool for non-randomized studies.

Results: We identified 13 studies where LC data was given for a total of 630 primary intradural spinal tumors, and our compiled analysis found that the pooled proportion of LC among them was 0.96 [95% CI: 0.92; 0.98]. Four subgroup analyses investigate the pooled proportions of LC among 4 studies with a total of 114 hemangioblastomas, 6 studies with a total of 121 meningiomas, 4 studies with a total of 196 schwannomas, and 5 studies with a total of 95 neurofibromas, which were found to be 0.96 [95% CI: 0.90; 0.98], 1.00 [95% CI: 0.37; 1.00], 0.95 [95% CI: 0.89; 0.97], and 0.95 [0.83; 0.99], respectively. We identified six studies that reported recurrence data for a total of 367 tumors, and the pooled proportion of recurrence among them was 0.03 [95% CI: 0.01; 0.07]. We were only able to conduct subgroup analyses of recurrence among 5 studies with a total of 58 meningiomas and 3 studies with a total of 80 schwannomas, and the pooled proportions of recurrence were 0.03 [95% CI: 0.01: 0.13] and 0.03 [95% CI: 0.01; 0.09], respectively.

Conclusion : Based on our study, using SRS for treating primary intradural spinal tumors achieves great results. Meningiomas had the best therapeutic outcome for LC, while there was no difference between meningiomas and schwannomas in terms of recurrence.