Tufts Medical Center Experience with Long Term Follow up of Vestibular Schwannoma Treated with Gamma Knife Stereotactic Radiosurgery: Novel Finding of Delayed Pseudoprogression

Aneurysmal bone cysts (ABCs) are an uncommon entity predominantly encountered in the pediatric population. The skull is rarely involved, but these cysts have been reported to arise in the skull base. Traditional treatment has been with surgery alone; however, there is a gathering body of literature that reports alternative treatments that can achieve long-term disease-free survival. However, these therapies are predominantly directed at peripheral skeletal lesions. To the authors’ knowledge, this report is the first to describe long-term follow-up of the efficacy of Gamma Knife stereotactic radiosurgery for treatment of ABC residuum in the skull base that resulted in long-term patient stability and likely ABC obliteration.

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Cavernous sinus meningiomas

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA ◽

10.22290/jbnc.v20i2.983 ◽

2018 ◽

Vol 20 (2) ◽

pp. 110-118

Author(s):

Roberto Spiegelmann ◽

Zvi R. Cohen ◽

Uzi Nissim

Keyword(s):

Stereotactic Radiosurgery ◽

Cavernous Sinus ◽

Linear Accelerator ◽

Medical Center ◽

Neurological Complications ◽

Formidable Challenge ◽

Long Term Follow Up ◽

Low Incidence

Introduction: Tumors of the cranial base arising from or partially involving the cavernous sinus have represented a formidable challenge to neurosurgeons. Stereotactic radiosurgery represents an alternative to microsurgery for the management of cavernous sinus meningiomas. The present study aims to evaluate the results of radiosurgery in a large series of patients treated with a linear accelerator with a long-term follow-up. Patients and Methods: From 1993 through 2007, 462 patients with meningiomas underwent radiosurgery at the Chaim Sheba Medical Center LINAC radiosurgery unit. Of those, 117 had tumors involving predominantly the cavernous sinus. A mean follow-up of 67 months was obtained in 102 patients (range:12 to 180 months). Patients’ age ranged from 31 to 86 years (mean 57). Seventy two (70%) were females. Thirty five patients (34.3%) were initially submitted to microsurgery and 67 (65.6%) underwent stereotactic radiosurgery as the first treatment option. Patients were treated using a linear accelerator with cylindrical collimators in 44 patients (43.1%) and a minimultileaf collimator in 58 patients (56.8%). The prescription dose was delivered to the 60 to 80% isodose line (mean, 68%) in patients treated with cylindrical collimators, and to the 80% in those treated with a single conformal isocenter. Doses ranged between 12 and 17.5 Gy (mean, 13.5 Gy). Median tumor volume was 7.2 cm3 (range 0.61–23 cm3). Results: All patients were available for follow-up at 12 to 180 months after treatment (mean, 68 months; median, 60 months). The actuarial control rate was 98%. Fifty nine patients (58%) had a volume reduction and forty one (40%) had stable tumor volumes at the end of follow-up. Two tumors grew. Overall, 4 patients had a new lasting neurological deficit (facial hypesthesia or pain in two, trochlear neuropathy in two, and visual defect in one), for an incidence of 4% in persistent neurological complications. Conclusions: This series of linear accelerator radiosurgery confirms that in the short and long term, radiosurgery affords excellent control for cavernous sinus meningiomas with a very low incidence of complications. Radiosurgery can thus be regarded as the treatment of choice for cavernous sinus meningiomas.

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Clinical and Radiologic Results from the Long-Term Follow-Up of More than 10 Years in Patients Undergoing Gamma Knife Radiosurgery for Vestibular Schwannoma

The Nerve ◽

10.21129/nerve.2019.5.1.7 ◽

2019 ◽

Vol 5 (1) ◽

pp. 7-14

Author(s):

Min Woo Kim ◽

Su Bum Lee ◽

Do Hoon Kwon ◽

Jeong Hoon Kim ◽

Chang Jin Kim ◽

...

Keyword(s):

Gamma Knife ◽

Vestibular Schwannoma ◽

Gamma Knife Radiosurgery ◽

Long Term Follow Up

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The Effect of Prescription Isodose Variation on Tumor Control and Toxicities in Stereotactic Radiosurgery for Sporadic Vestibular Schwannoma: Propensity Score-Matched Case–Control Study

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0040-1718908 ◽

2021 ◽

Author(s):

Achiraya Teyateeti ◽

Christopher S. Graffeo ◽

Avital Perry ◽

Eric J. Tryggestad ◽

Paul D. Brown ◽

...

Keyword(s):

Propensity Score ◽

Stereotactic Radiosurgery ◽

Vestibular Schwannoma ◽

Hearing Preservation ◽

Tumor Control ◽

Gamma Knife Stereotactic Radiosurgery ◽

The Impact ◽

Prescription Isodose

Abstract Objective Vestibular schwannoma (VS) treated with Gamma Knife stereotactic radiosurgery (SRS) was typically performed at 50% isodose line (IDL50); however, the impact of IDL variation on outcomes is poorly understood. This study aimed to compare tumor control (TC) and toxicities between treatment at 40% (IDL40) and 50% (IDL50). Methods and Materials Sporadic/unilateral VS patients treated with SRS dose 12 to 14 Gy and prescription isodose volume ≤10cm3 were included. Propensity score matching was applied to IDL40 cohort to generate an IDL50 companion cohort, adjusting for age and prescription isodose volume. After exclusion of patients with follow-up <24 months, there were 30 and 28 patients in IDL40 and IDL50 cohorts, respectively. Results Median follow-up time was 96 months (24–225 months). Actuarial and radiographic TC rates were 91.8% and clinical TC was 96.2% both at 5 and 10 years. TC was higher in IDL40 cohort but not significant (96.4 vs. 86.7%; p = 0.243). Hearing preservation (HP) rates were 71.9 and 39.2% at 5- and 10-year intervals, with significantly higher rates of HP noted in IDL40 cohort (83.3 vs. 57.1% at 5-year interval; 62.5 vs. 11.4% at 10-year interval; p = 0.017). Permanent facial neuropathy occurred in two patients, both from the IDL50 cohort (3.5%). Rates of post-SRS steroid treatment or shunt placement for hydrocephalus were slightly higher in IDL50 patients (6.9 vs. 17.9%; p = 0.208 and 3.3 vs. 7.1%; p = 0.532). Conclusion For treatment of VS with SRS, dose prescription at IDL40 or IDL50 provides excellent long-term TC and toxicity profiles. IDL40 may be associated with improved long-term HP.

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Comparison of the surgical and follow-up costs associated with microsurgical resection and stereotactic radiosurgery for vestibular schwannoma

Journal of Neurosurgery ◽

10.3171/jns/2008/108/6/1220 ◽

2008 ◽

Vol 108 (6) ◽

pp. 1220-1224 ◽

Cited By ~ 27

Author(s):

Ritesh Banerjee ◽

James P. Moriarty ◽

Robert L. Foote ◽

Bruce E. Pollock

Keyword(s):

Confidence Interval ◽

Stereotactic Radiosurgery ◽

Vestibular Schwannoma ◽

Mayo Clinic ◽

Long Term Follow Up ◽

Patient Groups ◽

Microsurgical Resection ◽

Mean Cost

Object The best approach to the management of vestibular schwannoma (VS) remains controversial. The aim of this study is to analyze the initial and follow-up costs of resection and stereotactic radiosurgery for patients with VS. Methods Initial and follow-up costs in 53 cases in which patients with unilateral, previously unoperated VSs > 3 cm underwent resection (21 cases) or radiosurgery (32 cases) at the Mayo Clinic from June 2000 until July 2002 were analyzed for 36 months. Follow-up treatment-specific utilization records were gathered prospectively for patients not returning to the Mayo Clinic after treatment. Six-month moving averages of incremental follow-up costs were calculated for the 2 patient groups. Results The mean cost of surgery in the microsurgery group was $23,788 (95% confidence interval $22,280–$24,842) compared with $16,143 (95% confidence interval $15,277–$17,545) for the radiosurgical group. Mean incremental follow-up costs per month for patients in the microsurgery group started just > $1000 per month, decreased steadily, and remained < $70 per month by the 10th month of follow-up. Mean incremental follow-up costs per month for patients in the radiosurgery group were <$10 per month for the first few months and thereafter increased to as much as $200 per month. Conclusions Although the total cost of microsurgery is higher due to the costs of hospitalization, follow-up costs for radiosurgery are greater in general. From a societal perspective, radiosurgery is less expensive than microsurgical resection provided that the rate of tumor progression after radiosurgery remains low with long-term follow-up.

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Long-term follow-up studies of Gamma Knife surgery with a low margin dose for vestibular schwannoma

Journal of Neurosurgery ◽

10.3171/2012.7.gks12783 ◽

2012 ◽

Vol 117 (Special_Suppl) ◽

pp. 57-62 ◽

Cited By ~ 21

Author(s):

Shibin Sun ◽

Ali Liu

Keyword(s):

Gamma Knife ◽

Vestibular Schwannoma ◽

Facial Palsy ◽

Gamma Knife Surgery ◽

Tumor Control ◽

Trigeminal Neuropathy ◽

Brainstem Compression ◽

Long Term Follow Up

Object The aim of this study was to assess long-term clinical outcomes in patients who underwent Gamma Knife surgery (GKS) with a low margin dose—14 Gy or less—to treat vestibular schwannoma (VS) unrelated to neurofibromatosis Type II. Methods Between December 1994 and December 2001, 200 patients with VSs underwent GKS, which was performed using the Leksell Gamma Knife model B. More than 10 years of follow-up is available in these patients. One hundred ninety patients (88 male and 102 female patients) were followed up using MRI (follow-up rate 95%). The mean age of these patients was 50.6 years (range 10–77 years). Gamma Knife surgery was the primary treatment for VS in 134 cases (70.5%) and was an adjunctive management approach in 56 cases (29.5%). The median tumor margin dose was 13.0 Gy (range 6.0–14.4 Gy), and the median maximum tumor dose was 28.0 Gy (range 15.0–60.0 Gy). The median tumor volume was 3.6 cm3 (range 0.3–27.3 cm3). The median duration of follow-up in these patients was 109 months (range 8–195 months). Results In the 190 patients, the latest follow-up MRI studies demonstrated tumor regression in 122 patients (64.2%), stable tumor in 48 patients (25.3%), and tumor enlargement in 20 patients (10.5%). The total rate of tumor control was 89.5%. Using the Kaplan-Meier method, the authors found the estimated 3-, 5-, 10-, and 15-year tumor control rates to be 95%, 93%, 86%, and 79%, respectively; and the estimated 3-, 5-, and 10-year hearing preservation rates to be 96%, 92%, and 70%, respectively. Twenty-six patients (13.7%) exhibited transient mild facial palsy or facial spasm, and 2 patients (1.1%) suffered persistent mild facial palsy. Thirty-nine patients (20.5%) had transient trigeminal neuropathy, and 5 patients (2.6%) suffered from persistent mild facial numbness. The incidence of persistent severe facial and trigeminal neuropathy was 0.0%. Conclusions With a low prescribed margin dose of 14 Gy or less, GKS was confirmed to provide long-term tumor control for small to medium-sized VSs and largely to prevent cranial nerves from iatrogenic injury. Based on the findings of this study, GKS is also a reasonable option for the treatment of large, heterogeneously enhancing tumors without symptomatic brainstem compression. Gamma Knife surgery can preserve a high quality of life for most patients with VS who do not have symptomatic brainstem compression. Long-term follow-up is required because of the risk of delayed recurrence of VS.

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Stereotactic Radiosurgery for Acoustic Neuroma: A Canadian Perspective

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100034338 ◽

1998 ◽

Vol 25 (4) ◽

pp. 310-314 ◽

Cited By ~ 1

Author(s):

Ian B. Ross ◽

Charles H. Tator

Keyword(s):

Stereotactic Radiosurgery ◽

Gamma Knife ◽

Acoustic Neuroma ◽

Radiation Treatment ◽

Significant Risk ◽

Conventional Surgery ◽

Canadian Perspective ◽

Long Term Follow Up

ABSTRACT:Stereotactically delivered radiation is now an accepted treatment for patients with acoustic neuroma. In some cases, patient preference may be the reason for its selection, while in others neurosurgeons may select it for patients who are elderly or have significant risk factors for conventional surgery. The majority of patients with acoustic neuroma treatment with stereotactic radiosurgery have been treated with the Gamma Knife, with follow ups of over 25 years in some instances. Other radiosurgical modalities utilizing the linear accelerator have been developed and appear promising, but there is no long-term follow up. Canada does not possess a Gamma Knife facility, and its government-funded hospital and medical insurance agencies have made it difficult for patients to obtain reimbursement for Gamma Knife treatments in other countries. We review the literature to date on the various forms of radiation treatment for acoustic neuroma and discuss the current issues facing physicians and patients in Canada who wish to obtain their treatment of choice.

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