Results of three or more Gamma Knife radiosurgery procedures for recurrent trigeminal neuralgia.

OBJECTIVE: Gamma Knife radiosurgery (GKRS) is an established surgical option for the treatment of trigeminal neuralgia (TN), particularly for high-risk surgical candidates and those with recurrent pain. However, outcomes after three or more GKRS treatments have rarely been reported. Herein, the authors reviewed outcomes among patients who had undergone three or more GKRS procedures for recurrent TN. METHODS: The authors conducted a multicenter retrospective analysis of patients who had undergone at least three GKRS treatments for TN between July 1997 and April 2019 at two different institutions. Clinical characteristics, radiosurgical dosimetry and technique, pain outcomes, and complications were reviewed. Pain outcomes were scored on the Barrow Neurological Institute (BNI) scale, including time to pain relief (BNI score ≤ III) and recurrence (BNI score > III). RESULTS: A total of 30 patients were identified, including 16 women and 14 men. Median pain duration prior to the first GKRS treatment was 10 years. Three patients (10%) had multiple sclerosis. Time to pain relief was longer after the third treatment (p = 0.0003), whereas time to pain recurrence was similar across each of the successive treatments (p = 0.842). Complete or partial pain relief was achieved in 93.1% of patients after the third treatment. The maximum pain relief achieved after the third treatment was significantly better among patients with no prior percutaneous procedures (p = 0.0111) and patients with shorter durations of pain before initiation of GKRS therapy (p = 0.0449). New or progressive facial sensory dysfunction occurred in 29% of patients after the third GKRS treatment and was reported as bothersome in 14%. One patient developed facial twitching, while another experienced persistent lacrimation. No statistically significant predictors of adverse effects following the third treatment were found. Over a median of 39 months of follow-up, 77% of patients maintained complete or partial pain relief. Three patients underwent a fourth GKRS treatment, including one who ultimately received five treatments; all of them reported sustained pain relief at the extended follow-up. CONCLUSIONS: The authors describe the largest series to date of patients undergoing three or more GKRS treatments for refractory TN. A third treatment may produce outcomes similar to those of the first two treatments in terms of long-term pain relief, recurrence, and adverse effects.

Improving the Prognostic Value of Disease-Specific Graded Prognostic Assessment Model for Renal Cell Carcinoma by Incorporation of Cumulative Intracranial Tumor Volume.

BACKGROUND: We tested the prognostic value of cumulative intracranial tumor volume (CITV) in the context of a disease-specific Graded Prognostic Assessment (ds-GPA) model for renal cell carcinoma (RCC) patients with brain metastasis (BM) treated with stereotactic radiosurgery (SRS). METHODS: Patient and tumor characteristics were collected from RCC cohorts with new BM who underwent SRS. Univariable and multivariable logistic regression model was used to test the prognostic value of CITV, Karnofsky Performance Score (KPS), and the number of BM. Net reclassification index (NRI) and integrated discrimination improvement (IDI) were used to assess whether CITV improved the prognostic utility of RCC ds-GPA. RESULTS: In univariable logistic regression models, CITV, KPS, and the number of BM were independently associated with RCC patient survival. In a multivariable Cox proportional hazard model, the association between CITV and survival remained robust after controlling for KPS and the number of BM (P = 0.042). The incorporation of the CITV into the RCC ds-GPA model (consisting of KPS and number of BM) improved prognostic accuracy with NRI >0 of 0.3156 (95% confidence interval [CI], 0.0883-0.5428; P = 0.0065) and IDI of 0.0151 (95% CI, 0.0036-0.0277; P = 0.0183). These findings were validated in an independent cohort of 107 SRS-treated RCC BM patients. CONCLUSION: CITV is an important prognostic variable in SRS-treated RCC patients with BM. The prognostic value of the ds-GPA scale for RCC brain metastasis was enhanced by the incorporation of CITV.

Survival Patterns of 5750 Stereotactic Radiosurgery-Treated Patients with Brain Metastasis as a Function of the Number of Lesions.

BACKGROUND: The number of brain metastases (BMs) plays an important role in the decision between stereotactic radiosurgery (SRS) and whole-brain radiation therapy. METHODS: We analyzed the survival of 5750 SRS-treated patients with BM as a function of BM number. Survival analyses were performed with Kaplan-Meier analysis as well as univariate and multivariate Cox proportional hazards models. RESULTS: Patients with BMs were first categorized as those with 1, 2-4, and 5-10 BMs based on the scheme proposed by Yamamoto et al. (Lancet Oncology 2014). Median overall survival for patients with 1 BM was superior to those with 2-4 BMs (7.1 months vs. 6.4 months, P = 0.009), and survival of patients with 2-4 BMs did not differ from those with 5-10 BMs (6.4 months vs. 6.3 months, P = 0.170). The median survival of patients with >10 BMs was lower than those with 2-10 BMs (6.3 months vs. 5.5 months, P = 0.025). In a multivariate model that accounted for age, Karnofsky Performance Score, systemic disease status, tumor histology, and cumulative intracranial tumor volume, we observed a ∼10% increase in hazard of death when comparing patients with 1 versus 2-10 BMs (P < 0.001) or 10 versus >10 BMs (P < 0.001). When BM number was modeled as a continuous variable rather than using the classification by Yamamoto et al., we observed a step-wise 4% increase in the hazard of death for every increment of 6-7 BM (P < 0.001). CONCLUSIONS: The contribution of BM number to overall survival is modest and should be considered as one of the many variables considered in the decision between SRS and whole-brain radiation therapy.

Management patterns of patients with cerebral metastases who underwent multiple stereotactic radiosurgeries.

With escalating focus on cost containment, there is increasing scrutiny on the practice of multiple stereotactic radiosurgeries (SRSs) for patients with cerebral metastases distant to the initial tumor site. Our goal was to determine the survival patterns of patients with cerebral metastasis who underwent multiple SRSs. We retrospectively analyzed survival outcomes of 801 patients with 3683 cerebral metastases from primary breast, colorectal, lung, melanoma and renal histologies consecutively treated at the University of California, San Diego/San Diego Gamma Knife Center (UCSD/SDGKC), comparing the survival pattern of patients who underwent a single (n = 643) versus multiple SRS(s) (n = 158) for subsequent cerebral metastases. Findings were recapitulated in an independent cohort of 2472 patients, with 26,629 brain metastases treated with SRS at the Katsuta Hospital Mito GammaHouse (KHMGH). For the UCSD/SDGKC cohort, no significant difference in median survival was found for patients undergoing 1, 2, 3, or ≥4 SRS(s) (median survival of 167, 202, 129, and 127 days, respectively). Median intervals between treatments consistently ranged 140-178 days irrespective of the number of SRS(s) (interquartile range 60-300; p = 0.25). Patients who underwent >1 SRSs tend to be younger, with systemic disease control, harbor lower cumulative tumor volume but increased number of metastases, and have primary melanoma (p < 0.001, <0.001, <0.001, 0.02, and 0.009, respectively). Comparable results were found in the KHMGH cohort. Using an independent validation study design, we demonstrated comparable overall survival between judiciously selected patients who underwent a single or multiple SRS(s).

Stereotactic Radiosurgery Treatment of Trigeminal Neuralgia: Clinical Outcomes and Prognostic Factors.

BACKGROUND: Stereotactic radiosurgery (SRS) is a minimally invasive surgical option for the treatment of trigeminal neuralgia (TN). Here we review our institutional experience to identify prognostic factors associated with pain relief after SRS. METHODS: 263 patients with TN treated at the University of California, San Diego/San Diego Gamma Knife (2001-2013) were followed for more than 6 months. Univariate and multivariate Cox proportional hazard models analysis of factors associated with outcome was performed. RESULTS: Of the 263 patients, 229 (87%) presented with classical idiopathic TN, 31 (12%) presented with atypical TN, and 4 (1%) presented with secondary TN. 143 (54%) had undergone prior treatment. Most patients were treated with 85 (52%) or 90 Gy (42%). 79% of the SRS treated patients experienced a favorable response (defined as Barrow Neurological Institute Pain Scale <3 pain relief), with a median time to relief of 2.5 months. In a multivariate analysis, diagnosis of classical TN, previous percutaneous procedures, and age older than 70 years were associated with favorable responses; classical TN was associated with sustained pain relief. Dose prescription >85 Gy and prior SRS were associated with bothersome facial numbness posttreatment. For patients presenting with classical TN, diagnosis of multiple sclerosis (MS) did not decrease the likelihood of pain relief after SRS. CONCLUSIONS: Excellent TN pain relief was achieved with the delivery of 85 Gy in a single-shot, 4-mm isocenter SRS targeting the dorsal root entry zone. Patients with classical TN, with age older than 70 years, or who underwent previous percutaneous procedures were more likely to benefit from SRS. SRS is efficacious in patients with classical TN despite concurrent diagnosis of MS.