SRS47 - Stereotactic radiosurgery for trigeminal neuralgia in patients with multiple sclerosis: a comparative institutional review

Abstract Purpose Trigeminal neuralgia (TN) in patients with multiple sclerosis (MS) presents therapeutic challenges. This study evaluates the outcomes of stereotactic radiosurgery (SRS) for TN in patients with and without MS, focusing on treatment response, relapse, retreatment, and toxicity. Methods We conducted a retrospective electronic chart review of 83 patients treated with SRS for TN in our institution. Patients were stratified by MS status. Data collected included treatment response, toxicities, relapse, time to relapse, retreatment, and toxicities (excluding fatigue). Rates were compared between MS (n = 18) and non-MS (n = 65) groups. Results Initial response rates were similar between groups (MS: 72.2%, non-MS: 75.4%). However, MS patients experienced a notably higher rate of relapse (38.9 versus 20.0%) and longer median time to relapse (15.0 months versus 7.5 months). Retreatment was also more frequent among MS patients (16.7 versus 7.7%). Treatment related toxicity was lower in MS patients (11.1%) compared to non-MS patients (29.2%), and no high grade toxicities were observed in either group. Conclusions While SRS provides a comparable initial response in MS and non-MS patients with TN, MS patients are more likely to experience relapses and require retreatment. The lower observed toxicity in MS patients may reflect altered nerve characteristics or reporting variability. Further investigation is underway to assess whether treatment related variables may help predict relapse risk in this population.