Top 25 Cited Gamma Knife® Surgery Articles—Meningioma
Jason P. Sheehan, Robert M. Starke, Hideyuki Kano, Gene H. Barnett, David Mathieu, Veronica Chiang, James B. Yu, Judith Hess, Heyoung L. McBride, Norissa Honea, Peter Nakaji, John Y. K. Lee, Gazanfar Rahmathulla, Wendi A. Evanoff, Michelle Alonso-Basanta and L. Dade Lunsford
Posterior fossa meningiomas represent a common yet challenging clinical entity. They are often associated with neurovascular structures and adjacent to the brainstem. Resection can be undertaken for posterior fossa meningiomas, but residual or recurrent tumor is frequent. Stereotactic radiosurgery (SRS) has been used to treat meningiomas, and this study evaluates the outcome of this approach for those located in the posterior fossa.
At 7 medical centers participating in the North American Gamma Knife Consortium, 675 patients undergoing SRS for a posterior fossa meningioma were identified, and clinical and radiological data were obtained for these cases. Females outnumbered males at a ratio of 3.8 to 1, and the median patient age was 57.6 years (range 12–89 years). Prior resection was performed in 43.3% of the patient sample. The mean tumor volume was 6.5 cm3, and a median margin dose of 13.6 Gy (range 8–40 Gy) was delivered to the tumor.
At a mean follow-up of 60.1 months, tumor control was achieved in 91.2% of cases. Actuarial tumor control was 95%, 92%, and 81% at 3, 5, and 10 years after radiosurgery. Factors predictive of tumor progression included age greater than 65 years (hazard ratio [HR] 2.36, 95% CI 1.30–4.29, p = 0.005), prior history of radiotherapy (HR 5.19, 95% CI 1.69–15.94, p = 0.004), and increasing tumor volume (HR 1.05, 95% CI 1.01–1.08, p = 0.005). Clinical stability or improvement was achieved in 92.3% of patients. Increasing tumor volume (odds ratio [OR] 1.06, 95% CI 1.01–1.10, p = 0.009) and clival, petrous, or cerebellopontine angle location as compared with petroclival, tentorial, and foramen magnum location (OR 1.95, 95% CI 1.05–3.65, p = 0.036) were predictive of neurological decline after radiosurgery. After radiosurgery, ventriculoperitoneal shunt placement, resection, and radiation therapy were performed in 1.6%, 3.6%, and 1.5%, respectively.
Stereotactic radiosurgery affords a high rate of tumor control and neurological preservation for patients with posterior fossa meningiomas. Those with a smaller tumor volume and no prior radiation therapy were more likely to have a favorable response after radiosurgery. Rarely, additional procedures may be required for hydrocephalus or tumor progression.
Robert M. Starke, Colin J. Przybylowski, Mukherjee Sugoto, Francis Fezeu, Ahmed J. Awad, Dale Ding, James H. Nguyen and Jason P. Sheehan
Stereotactic radiosurgery (SRS) has become a common treatment modality for intracranial meningiomas. Skull base meningiomas greater than 8 cm3 in volume have been found to have worse outcomes following SRS. When symptomatic, patients with these tumors are often initially treated with resection. For tumors located in close proximity to eloquent structures or in patients unwilling or unable to undergo a resection, SRS may be an acceptable therapeutic approach. In this study, the authors review the SRS outcomes of skull base meningiomas greater than 8 cm3 in volume, which corresponds to a lesion with an approximate diameter of 2.5 cm.
The authors reviewed the data in a prospectively compiled database documenting the outcomes of 469 patients with skull base meningiomas treated with single-session Gamma Knife radiosurgery (GKRS). Seventy-five patients had tumors greater than 8 cm3 in volume, which was defined as a large tumor. All patients had a minimum follow-up of 6 months, but patients were included if they had a complication at any time point. Thirty patients were treated with upfront GKRS, and 45 were treated following microsurgery. Patient and tumor characteristics were assessed to determine predictors of new or worsening neurological function and tumor progression following GKRS.
After a mean follow-up of 6.5 years (range 0.5–21 years), the tumor volume was unchanged in 37 patients (49%), decreased in 26 patients (35%), and increased in 12 patients (16%). Actuarial rates of progression-free survival at 3, 5, and 10 years were 90.3%, 88.6%, and 77.2%, respectively. Four patients had new or worsened edema following GKRS, but preexisting edema decreased in 3 patients. In Cox multivariable analysis, covariates associated with tumor progression were 1) presentation with any cranial nerve (CN) deficit from III to VI (hazard ratio [HR] 3.78, 95% CI 1.91–7.45; p < 0.001), history of radiotherapy (HR 12.06, 95% CI 2.04–71.27; p = 0.006), and tumor volume greater than 14 cm3 (HR 6.86, 95% CI 0.88–53.36; p = 0.066). In those patients with detailed clinical follow-up (n = 64), neurological function was unchanged in 37 patients (58%), improved in 16 patients (25%), and deteriorated in 11 patients (17%). In multivariate analysis, the factors predictive of new or worsening neurological function were history of surgery (OR 3.00, 95% CI 1.13–7.95; p = 0.027), presentation with any CN deficit from III to VI (OR 3.94, 95% CI 1.49–10.24; p = 0.007), and decreasing maximal dose (OR 0.76, 95% CI 0.63–0.93; p = 0.007). Tumor progression was present in 64% of patients with new or worsening neurological decline.
Stereotactic radiosurgery affords a reasonable rate of tumor control for large skull base meningiomas and does so with a low incidence of neurological deficits. Those with a tumor less than 14 cm3 in volume and without presenting CN deficit from III to VI were more likely to have effective tumor control.
Jason P. Sheehan, Robert M. Starke, Hideyuki Kano, Anthony M. Kaufmann, David Mathieu, Fred A. Zeiler, Michael West, Samuel T. Chao, Gandhi Varma, Veronica L. S. Chiang, James B. Yu, Heyoung L. McBride, Peter Nakaji, Emad Youssef, Norissa Honea, Stephen Rush, Douglas Kondziolka, John Y. K. Lee, Robert L. Bailey, Sandeep Kunwar, Paula Petti and L. Dade Lunsford
Parasellar and sellar meningiomas are challenging tumors owing in part to their proximity to important neurovascular and endocrine structures. Complete resection can be associated with significant morbidity, and incomplete resections are common. In this study, the authors evaluated the outcomes of parasellar and sellar meningiomas managed with Gamma Knife radiosurgery (GKRS) both as an adjunct to microsurgical removal or conventional radiation therapy and as a primary treatment modality.
A multicenter study of patients with benign sellar and parasellar meningiomas was conducted through the North American Gamma Knife Consortium. For the period spanning 1988 to 2011 at 10 centers, the authors identified all patients with sellar and/or parasellar meningiomas treated with GKRS. Patients were also required to have a minimum of 6 months of imaging and clinical follow-up after GKRS. Factors predictive of new neurological deficits following GKRS were assessed via univariate and multivariate analyses. Kaplan-Meier analysis and Cox multivariate regression analysis were used to assess factors predictive of tumor progression.
The authors identified 763 patients with sellar and/or parasellar meningiomas treated with GKRS. Patients were assessed clinically and with neuroimaging at routine intervals following GKRS. There were 567 females (74.3%) and 196 males (25.7%) with a median age of 56 years (range 8–90 years). Three hundred fifty-five patients (50.7%) had undergone at least one resection before GKRS, and 3.8% had undergone prior radiation therapy. The median follow-up after GKRS was 66.7 months (range 6–216 months). At the last follow-up, tumor volumes remained stable or decreased in 90.2% of patients. Actuarial progression-free survival rates at 3, 5, 8, and 10 years were 98%, 95%, 88%, and 82%, respectively. More than one prior surgery, prior radiation therapy, or a tumor margin dose < 13 Gy significantly increased the likelihood of tumor progression after GKRS.
At the last clinical follow-up, 86.2% of patients demonstrated no change or improvement in their neurological condition, whereas 13.8% of patients experienced symptom progression. New or worsening cranial nerve deficits were seen in 9.6% of patients, with cranial nerve (CN) V being the most adversely affected nerve. Functional improvements in CNs, especially in CNs V and VI, were observed in 34% of patients with preexisting deficits. New or worsened endocrinopathies were demonstrated in 1.6% of patients; hypothyroidism was the most frequent deficiency. Unfavorable outcome with tumor growth and accompanying neurological decline was statistically more likely in patients with larger tumor volumes (p = 0.022) and more than 1 prior surgery (p = 0.021).
Gamma Knife radiosurgery provides a high rate of tumor control for patients with parasellar or sellar meningiomas, and tumor control is accompanied by neurological preservation or improvement in most patients.
Seong-Hyun Park, Hideyuki Kano, Ajay Niranjan, John C. Flickinger and L. Dade Lunsford
To assess the long-term outcomes of stereotactic radiosurgery (SRS) for cerebellopontine angle (CPA) meningiomas, the authors retrospectively reviewed data from a 20-year experience. They evaluated progression-free survival as well as improvement, stabilization, or deterioration in clinical symptoms.
Seventy-four patients with CPA meningiomas underwent SRS involving various Gamma Knife technologies between 1990 and 2010. The most common presenting symptoms were dizziness or disequilibrium, hearing loss, facial sensory dysfunction, and headache. The median tumor volume was 3.0 cm3 (range 0.3–17.1 cm3), and the median radiation dose to the tumor margin was 13 Gy (range 11–16 Gy). The median follow-up period was 40 months (range 4–147 months).
At last imaging follow-up, the tumor volume had decreased in 46 patients (62%), remained stable in 26 patients (35%), and increased in 2 patients (3%). The progression-free survival after SRS was 98% at 1 year, 98% at 3 years, and 95% at 5 years. At the last clinical follow-up, 23 patients (31%) showed neurological improvement, 43 patients (58%) showed no change in symptoms or signs, and 8 patients (11%) had worsening symptoms or signs. The neurological improvement rate after SRS was 16% at 1 year, 31% at 3 years, and 40% at 5 years. The post-SRS deterioration rate was 5% at 1 year, 10% at 3 years, and 16% at 5 years. A multivariate analysis demonstrated that trigeminal neuralgia was the symptom most likely to worsen after SRS (HR 0.08, 95% CI 0.02–0.31; p = 0.001). Asymptomatic peritumoral edema occurred in 4 patients (5%) after SRS, and symptomatic adverse radiation effects developed in 7 patients (9%).
Stereotactic radiosurgery for CPA meningiomas provided a high tumor control rate and relatively low risk of ARE. Tumor compression of the trigeminal nerve by a CPA meningioma resulted in an increased rate of facial pain worsening in this patient experience.