Clinical and Imaging Outcomes After Trigeminal Schwannoma Radiosurgery: Results From a Multicenter, International Cohort Study.

BACKGROUND AND OBJECTIVES: An international, multicenter, retrospective study was conducted to evaluate the long-term clinical outcomes and tumor control rates after stereotactic radiosurgery (SRS) for trigeminal schwannoma. METHODS: Patient data (N = 309) were collected from 14 international radiosurgery centers. The median patient age was 50 years (range 11-87 years). Sixty patients (19%) had prior resections. Abnormal facial sensation was the commonest complaint (49%). The anatomic locations were root (N = 40), ganglion (N = 141), or dumbbell type (N = 128). The median tumor volume was 4 cc (range, 0.2-30.1 cc), and median margin dose was 13 Gy (range, 10-20 Gy). Factors associated with tumor control, symptom improvement, and adverse radiation events were assessed. RESULTS: The median and mean time to last follow-up was 49 and 65 months (range 6-242 months). Greater than 5-year follow-up was available for 139 patients (45%), and 50 patients (16%) had longer than 10-year follow-up. The overall tumor control rate was 94.5%. Tumors regressed in 146 patients (47.2%), remained unchanged in 128 patients (41.4%), and stabilized after initial expansion in 20 patients (6.5%). Progression-free survival rates at 3 years, 5 years, and 10 years were 91%, 86%, and 80 %. Smaller tumor volume (less than 8 cc) was associated with significantly better progression-free survival ( P = .02). Seventeen patients with sustained growth underwent further intervention at a median of 27 months (3-144 months). Symptom improvement was noted in 140 patients (45%) at a median of 7 months. In multivariate analysis primary, SRS ( P = .003) and smaller tumor volume ( P = .01) were associated with better symptom improvement. Adverse radiation events were documented in 29 patients (9%). CONCLUSION: SRS was associated with long-term freedom (10 year) from additional management in 80% of patients. SRS proved to be a valuable salvage option after resection. When used as a primary management for smaller volume tumors, both clinical improvement and prevention of new deficits were optimized.

Gamma Knife radiosurgery and refractory glossopharyngeal neuralgia: a single-center series with long-term follow-up.

We present our experience with Gamma Knife surgery (GKS) and refractory glossopharyngeal neuralgia (GPN), analyzing its usefulness and safety in patients with or without previous surgeries, another concomitant neuralgia, or retreats. In addition, we study some factors that could condition the outcome of this technique. According to our review, our follow-up is the longest in the literature. We performed the prospective study of 8 patients submitted to GKS between 2008 and 2020. We employed the Leksell radiosurgery Gamma Knife system. The cases were evaluated before and after surgery (3, 6, 12 months and then annually). The VAS (Visual Analogue Scale) and BNI (Barrow Neurological Institute) scale were used. The data were assessed with SPSS25. Our series was composed of 6 (75%) women and 2 (25%) men, with an average age of 59.5 ± 14.04 years. Six patients (75%) had one or more than one previous surgeries. The median follow-up time was 7.22 ± 3.66 years (1.08-12.5 years). In the short-term postoperative period (1 year), eight patients (100%) experienced significant pain relief (VAS, p = 0.012; BNI I-IIIb). After the last interview, 5 patients felt pain relief (62.5%) (BNI grade I = 3; BNI grade IIIa = 2); 3 patients (37.5%) (BNI grade IV) were retreated (MVD, 2; GKS, 1). We found no association between patients with long evolution time of disease (p = 0.356), previous surgeries (p = 0.206), or vascular contact (p = 0.673) and worse clinical results after GKS. Both morbidity and mortality were 0%. Our results suggest that GKS for treating drug-resistant GPN with high initial doses is both a minimally invasive and useful and effective therapeutic strategy, without permanent complications. It presents good results even in patients with one or more previous surgical interventions. These findings encourage us to use this non-invasive technique as initial therapy against the invasive options.