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Gerganov V, Petrov M, Sakelarova T. Schwannomas of Brain and Spinal Cord. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1405:331-362. [PMID: 37452944 DOI: 10.1007/978-3-031-23705-8_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Schwannomas are benign tumors originating from the Schwann cells of cranial or spinal nerves. The most common cranial schwannomas originate from the eight cranial nervevestibular schwannomas (VS). VS account for 6-8% of all intracranial tumors, 25-33% of the tumors localized in the posterior cranial fossa, and 80-94% of the tumors in the cerebellopontine angle (CPA). Schwannomas of other cranial nerves/trigeminal, facial, and schwannomas of the lower cranial nerves/are much less frequent. According to the World Health Organization (WHO), intracranial and intraspinal schwannomas are classified as Grade I. Some VS are found incidentally, but most present with hearing loss (95%), tinnitus (63%), disequilibrium (61%), or headache (32%). The neurological symptoms of VSs are mainly due to compression on the surrounding structures, such as the cranial nerves and vessels, or the brainstem. The gold standard for the imaging diagnosis of VS is MRI scan. The optimal management of VSs remains controversial. There are three main management options-conservative treatment or "watch-and-wait" policy, surgical treatment, and radiotherapy in all its variations. Currently, surgery of VS is not merely a life-saving procedure. The functional outcome of surgery and the quality of life become issues of major importance. The most appropriate surgical approach for each patient should be considered according to some criteria including indications, risk-benefit ratio, and prognosis of each patient. The approaches to the CPA and VS removal are generally divided in posterior and lateral. The retrosigmoid suboccipital approach is a safe and simple approach, and it is favored for VS surgery in most neurosurgical centers. Radiosurgery is becoming more and more available nowadays and is established as one of the main treatment modalities in VS management. Radiosurgery (SRS) is performed with either Gamma knife, Cyber knife, or linear accelerator. Larger tumors are being increasingly frequently managed with combined surgery and radiosurgery. The main goal of VS management is preservation of neurological function - facial nerve function, hearing, etc. The reported recurrence rate after microsurgical tumor removal is 0.5-5%. Postoperative follow-up imaging is essential to diagnose any recurrence.
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Affiliation(s)
- Venelin Gerganov
- International Neuroscience Institute, Hannover, Germany
- University Multiprofile Hospital for Active Treatment With Emergency Medicine N. I. Pirogov, Sofia, Bulgaria
| | - Mihail Petrov
- University Multiprofile Hospital for Active Treatment With Emergency Medicine N. I. Pirogov, Sofia, Bulgaria.
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Albano L, Deng H, Wei Z, Vodovotz L, Niranjan A, Lunsford LD. The longitudinal volumetric response of vestibular schwannomas after Gamma Knife radiosurgery. J Neurosurg 2022; 138:1273-1280. [PMID: 36087328 DOI: 10.3171/2022.7.jns22812] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 07/13/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Gamma Knife radiosurgery (GKRS) is an effective treatment for vestibular schwannomas (VSs) and has been used in > 100,000 cases worldwide. In the present study the authors sought to define the serial volumetric tumor response of Koos grade I-IV VS after radiosurgery. METHODS A total of 201 consecutive VS patients underwent GKRS at a single institution between 2015 and 2019. All patients had a minimum follow-up of 18 months and at least 2 interval postprocedure MRI scans. The contrast-enhanced tumor volumes were contoured manually and compared between pre- and post-GKRS imaging. The percentages of tumor volume change at 18 months (short-term follow-up) and up to 5 years after GKRS (long-term follow-up) were compared with the baseline tumor volume. An increase of 20% was considered a significant increase of tumor volume. Trends of tumor volume over time were assessed with linear models using time as a continuous variable. A test for linear trend was evaluated according to the initial Koos tumor classification. RESULTS Koos grade II VS was the most frequently occurring tumor (n = 74, 36.8%), followed by grade III (n = 57, 28.4%), grade I (n = 41, 20.4%), and grade IV (n = 29, 14.4%). The mean tumor volume at the time of GKRS was 2.12 ± 2.82 cm3 (range 0.12-18.77 cm3) and the median margin dose was 12 Gy. Short-term follow-up revealed that tumor volumes transiently increased in 34.2% and 28.4% of patients at 6 and 18 months, respectively, regardless of Koos grade. Linear regression analysis of Koos grade II, III, and IV tumors showed a significant longitudinal volume decrease on long-term follow-up. At last follow-up (median 30 months, range 18-54 months), 19 patients (9.4%) showed a persistent increase of tumor volume. Five patients received additional management after GKRS. CONCLUSIONS Although selected VS patients demonstrate an early and measurable transient volumetric increase after GKRS, > 90% have stable or reduced tumor volumes over an observed period of up to 5 years. Volumetric regression is most pronounced in Koos grade II, III, and IV tumors and may not be fully detectable until 3 years after GKRS.
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Affiliation(s)
- Luigi Albano
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Hansen Deng
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Zhishuo Wei
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Lena Vodovotz
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Ajay Niranjan
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - L Dade Lunsford
- 1Department of Neurological Surgery and.,2Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Özer H, Yazol M, Erdoğan N, Emmez ÖH, Kurt G, Öner AY. Dynamic contrast-enhanced magnetic resonance imaging for evaluating early response to radiosurgery in patients with vestibular schwannoma. Jpn J Radiol 2022; 40:678-688. [PMID: 35038116 DOI: 10.1007/s11604-021-01245-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 12/28/2021] [Indexed: 10/19/2022]
Abstract
PURPOSE This study aimed to use dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate early treatment response in vestibular schwannoma (VS) patients after radiosurgery. METHODS Twenty-four VS patients who underwent gamma knife radiosurgery were prospectively followed up for at least four years. DCE-MRI sequences, in addition to standard MRI protocol, were obtained prior to radiosurgery, at 3 and 6 months. Conventionally, treatment responses based on tumor volume changes were classified as regression or stable (RS), transient tumor enlargement (TTE), and continuous tumor enlargement (CTE). DCE-MRI parameters, such as Ktrans, Kep and Ve, were compared according to follow-up periods and between groups. The diagnostic performance was tested using receiver operating characteristic (ROC) curves. RESULTS Changes in tumor volume were as follows at the last 48 months of follow-up: RS in 11 patients (45.8%), TTE in 10 patients (41.7%), and CTE in three patients (12.5%). The median time required to distinguish TTE from CTE using conventional MRI was 12 months (range 9-18). The Ktrans and Ve were significantly decreased in patients with RS and TTE at 3 and 6 months, but did not differ significantly in patients with CTE. There were no significant differences in Ktrans and Ve between patients with RS and TTE at 3 and 6 months. Both Ktrans and Ve demonstrated high diagnostic performance in evaluating early treatment response to radiosurgery in patients with VS. CONCLUSION DCE-MRI may aid in the monitoring and early prediction of treatment response in patients with VS following radiosurgery.
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Affiliation(s)
- Halil Özer
- Department of Radiology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey.
| | - Merve Yazol
- Department of Radiology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Nesrin Erdoğan
- Department of Radiology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
| | - Ömer Hakan Emmez
- Department of Neurosurgery, Gazi University Faculty of Medicine, Ankara, Turkey
| | - Gökhan Kurt
- Department of Neurosurgery, Gazi University Faculty of Medicine, Ankara, Turkey
| | - Ali Yusuf Öner
- Department of Radiology, Gazi University Faculty of Medicine, Beşevler, 06500, Ankara, Turkey
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Fouard O, Daisne JF, Wanet M, Regnier M, Gustin T. Long-term volumetric analysis of vestibular schwannomas following stereotactic radiotherapy: Practical implications for follow-up. Clin Transl Radiat Oncol 2022; 33:1-6. [PMID: 34977365 PMCID: PMC8688865 DOI: 10.1016/j.ctro.2021.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/01/2021] [Accepted: 12/05/2021] [Indexed: 11/25/2022] Open
Abstract
Pseudoprogression may be a late phenomenon after radiosurgery. Loss of central contrast enhancement is not predictive of tumor control. No decision of salvage therapy should be made until the 6th year post-treatment.
Background and purpose Transient tumor swelling is a well-known phenomenon following radiotherapy for vestibular schwannomas (VS). We analyzed the long-term volumetric changes of VS after LINAC radiosurgery, in order to determine a time interval during which a true tumor progression can be distinguished from a pseudoprogression. Methods Among 63 patients with VS treated by one fraction or fractionated radiotherapy, we selected 52 of them who had a minimal follow-up of 5 years. Maximal axial diameter and three-dimensional tumor volume were measured on each MRI scan. Volume changes were interpreted using different error margins ranging from 10 to 20%. Patients were categorized according to the tumor evolution pattern over time. Results Median follow-up was 83 months. One tumor (1.9%) remained stable and 26.9% had continuous shrinkage. Applying an error margin of 13%, a transient tumor enlargement was observed in 63.5% of patients, with a first peak at 6–12 months and a late peak at 3–4 years. A true progression was suspected in 4 (7.7%) patients, tumor regrowth starting after the 3rd or 4th year post-treatment. Only one patient required salvage radiotherapy. Conclusion Transient swelling of VS following radiotherapy is generally an early phenomenon but may occur late. In the first 5 years, a true tumor progression cannot be differentiated from a pseudoprogression. A significant tumor expansion observed on 3 sequential MRI scans after the 3rd year may be suggestive of treatment failure. Long-term follow-up is therefore mandatory and no decision of salvage treatment should be made until the 6th year.
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Affiliation(s)
- O Fouard
- Neurosurgery Department, CHU UCL Namur site Godinne, Université Catholique de Louvain, Yvoir, Belgium
| | - J F Daisne
- Radiation Oncology Department, CHU UCL Namur Site Sainte-Elisabeth, Université Catholique de Louvain, Namur, Belgium.,Radiation Oncology Department, University Hospitals Leuven, Katholieke Universiteit Leuven, Leuven, Belgium.,Department of Oncology and Leuven Cancer Institute, Katholieke Universiteit Leuven, Leuven, Belgium
| | - M Wanet
- Radiation Oncology Department, CHU UCL Namur Site Sainte-Elisabeth, Université Catholique de Louvain, Namur, Belgium
| | - M Regnier
- Scientific Support Unit, CHU UCL Namur, Université catholique de Louvain, Namur, Belgium
| | - T Gustin
- Neurosurgery Department, CHU UCL Namur site Godinne, Université Catholique de Louvain, Yvoir, Belgium
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Teyateeti A, Graffeo CS, Perry A, Tryggestad EJ, Brown PD, Pollock BE, Link MJ. The Effect of Prescription Isodose Variation on Tumor Control and Toxicities in Stereotactic Radiosurgery for Sporadic Vestibular Schwannoma: Propensity Score-Matched Case–Control Study. Skull Base Surg 2021; 83:193-202. [DOI: 10.1055/s-0040-1718908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 09/03/2020] [Indexed: 10/22/2022]
Abstract
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 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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Affiliation(s)
- Achiraya Teyateeti
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States
- Department of Radiology, Division of Radiation Oncology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | | | - Avital Perry
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Eric J. Tryggestad
- Department of Radiation Physics, Mayo Clinic, Rochester, Minnesota, United States
| | - Paul D. Brown
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, United States
| | - Bruce E. Pollock
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, United States
| | - Michael J. Link
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, United States
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Long-term outcomes of patients with primary or residual vestibular schwannoma treated with LINAC-based stereotactic radiosurgery: a single-centre experience. JOURNAL OF RADIOTHERAPY IN PRACTICE 2020. [DOI: 10.1017/s1460396920000588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
AbstractAim:Vestibular schwannomas (VS) are benign slow-growing tumours treated either with microsurgery or stereotactic radiosurgery (SRS) or both. The aim of this study was to correlate the outcome factors—tumour control and adverse factors—facial nerve function and hearing loss with patient and treatment factors.Materials and methods:A retrospective review of the records of 98 patients with 99 VS treated from June 2007 to June 2014, all patients receiving Linear Accelerator (LINAC)-based SRS.Results:Median follow-up period was 5·6 years (range: 1–12 years). The response to treatment was stable disease in 37 (37·4%), regression in 46 (46·5%), asymptomatic minimal progression in 9 (9·1%) and symptomatic progression in 5 (5%) and unknown in 2 (2%) patients. There was no evidence of SRS induced tissue damage on magnetic resonance scans for any. Hearing preservation rate after SRS was 92%. The patients who developed worsening of facial function were predominantly in the cohort that had prior surgery.Findings:SRS is an effective modality to treat VS lesser than 3 cm in size. Tumour control rate was 95% with a median follow-up period of 5·6 years. The complication rates were 8% each for facial function worsening and worsening of hearing. Prior surgery was a statistically significant factor that affected facial nerve function deterioration.
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Langenhuizen PPJH, Sebregts SHP, Zinger S, Leenstra S, Verheul JB, de With PHN. Prediction of transient tumor enlargement using MRI tumor texture after radiosurgery on vestibular schwannoma. Med Phys 2020; 47:1692-1701. [PMID: 31975523 PMCID: PMC7217023 DOI: 10.1002/mp.14042] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 11/10/2022] Open
Abstract
PURPOSE Vestibular schwannomas (VSs) are uncommon benign brain tumors, generally treated using Gamma Knife radiosurgery (GKRS). However, due to the possible adverse effect of transient tumor enlargement (TTE), large VS tumors are often surgically removed instead of treated radiosurgically. Since microsurgery is highly invasive and results in a significant increased risk of complications, GKRS is generally preferred. Therefore, prediction of TTE for large VS tumors can improve overall VS treatment and enable physicians to select the most optimal treatment strategy on an individual basis. Currently, there are no clinical factors known to be predictive for TTE. In this research, we aim at predicting TTE following GKRS using texture features extracted from MRI scans. METHODS We analyzed clinical data of patients with VSs treated at our Gamma Knife center. The data was collected prospectively and included patient- and treatment-related characteristics and MRI scans obtained at day of treatment and at follow-up visits, 6, 12, 24 and 36 months after treatment. The correlations of the patient- and treatment-related characteristics to TTE were investigated using statistical tests. From the treatment scans, we extracted the following MRI image features: first-order statistics, Minkowski functionals (MFs), and three-dimensional gray-level co-occurrence matrices (GLCMs). These features were applied in a machine learning environment for classification of TTE, using support vector machines. RESULTS In a clinical data set, containing 61 patients presenting obvious non-TTE and 38 patients presenting obvious TTE, we determined that patient- and treatment-related characteristics do not show any correlation to TTE. Furthermore, first-order statistical MRI features and MFs did not significantly show prognostic values using support vector machine classification. However, utilizing a set of 4 GLCM features, we achieved a sensitivity of 0.82 and a specificity of 0.69, showing their prognostic value of TTE. Moreover, these results increased for larger tumor volumes obtaining a sensitivity of 0.77 and a specificity of 0.89 for tumors larger than 6 cm3 . CONCLUSIONS The results found in this research clearly show that MRI tumor texture provides information that can be employed for predicting TTE. This can form a basis for individual VS treatment selection, further improving overall treatment results. Particularly in patients with large VSs, where the phenomenon of TTE is most relevant and our predictive model performs best, these findings can be implemented in a clinical workflow such that for each patient, the most optimal treatment strategy can be determined.
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Affiliation(s)
- Patrick P J H Langenhuizen
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,Gamma Knife Center Tilburg, Department of Neurosurgery, ETZ Hospital, Tilburg, The Netherlands
| | - Sander H P Sebregts
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Svetlana Zinger
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Sieger Leenstra
- Department of Neurosurgery, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jeroen B Verheul
- Gamma Knife Center Tilburg, Department of Neurosurgery, ETZ Hospital, Tilburg, The Netherlands
| | - Peter H N de With
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
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De Sanctis P, Green S, Germano I. Communicating hydrocephalus after radiosurgery for vestibular schwannomas: does technique matter? A systematic review and meta-analysis. J Neurooncol 2019; 145:365-373. [PMID: 31621039 DOI: 10.1007/s11060-019-03305-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 09/30/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Communicating hydrocephalus (cHCP) after radiosurgery (RS) for vestibular schwannomas (VS) has been reported. Many hypothetical mechanisms for this pathology have been proposed without consensus. The aim of this study is to determine if the platform used to treat the disease, Gamma Knife (GK) versus linear accelerator (LINAC)-based RS, makes a difference in outcome. METHODS We conducted a meta-analysis of databases PubMed and Cochrane to identify all articles for the period January 2000-August 2018 with the following inclusion criteria: (1) VS treated with single fraction SRS (2) > 10 patients (3) original reports only (4) hydrocephalus reported as complication (5) human study. RESULTS A total of 7039 and 988 VS patients reported in 35 and 10 papers were treated with GK or LINAC RS, respectively. Demographic baseline characteristics not reported in aggregate did not differ between the two groups. The incidence of cHCP was 3% [95% CI 2-4] and 2% [95% CI 1-3] for GK and LINAC RS patients, respectively. Surgical CSF diversion was performed in 88% and 68% of patients evaluated for cHPC in the GK and LINAC group, respectively. Follow-up range was 30-150 and 29-92 months for GK and LINAC, respectively. CONCLUSIONS The incidence of cHCP following RS for VS is very low in both GK and LINAC treated patients, albeit not identical. The higher reported surgical intervention rate for VS patients treated with GK RS might be multi-factorial, including longer follow-up in the GK group.
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Affiliation(s)
| | - Sheryl Green
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Isabelle Germano
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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Patel KS, Ng E, Kaur T, Miao T, Kaprealian T, Lee P, Pouratian N, Selch MT, De Salles AAF, Gopen Q, Tenn S, Yang I. Increased cochlear radiation dose predicts delayed hearing loss following both stereotactic radiosurgery and fractionated stereotactic radiotherapy for vestibular schwannoma. J Neurooncol 2019; 145:329-337. [PMID: 31552587 DOI: 10.1007/s11060-019-03299-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 09/18/2019] [Indexed: 12/25/2022]
Abstract
PURPOSE Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) are noninvasive therapies for vestibular schwannomas providing excellent tumor control. However, delayed hearing loss after radiation therapy remains an issue. One potential target to for improving hearing rates is limiting radiation exposure to the cochlea. METHODS We retrospectively reviewed 100 patients undergoing either SRS with 12 Gy (n = 43) or fSRT with 50 Gy over 28 fractions (n = 57) for vestibular schwannoma. Univariate and multivariate analysis were carried out to identify predictors of hearing loss as measured by the Gardner Robertson scale after radiation therapy. RESULTS Deterioration of hearing occurred in 30% of patients with SRS and 26% with fSRT. The overall long term (> 2 year) progression rates were 20% for SRS and 16% for fSRT. Patients with a decrease in their Gardner Robertson hearing score and those that loss serviceable hearing had significantly higher average minimal doses to the cochlea in both SRS and fSRT cohorts. ROC analysis showed that a cut off of 5 Gy and 35 Gy, for SRS and fSRT respectively, predicted hearing loss with high sensitivity/specificity. CONCLUSION Our data suggests the minimal dose of radiation that the cochlear volume is exposed to is a predictor of delayed hearing loss after either SRS or fSRT. A threshold of 5 Gy/35 Gy may lead to improved hearing preservation after radiotherapy. Further prospective multi center studies can further elucidate this mechanism.
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Affiliation(s)
- Kunal S Patel
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, USA
| | - Edwin Ng
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, USA
| | - Taranjit Kaur
- Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | - Tyler Miao
- Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | - Tania Kaprealian
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Percy Lee
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Nader Pouratian
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, USA
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Michael T Selch
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Antonio A F De Salles
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, USA
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Quinton Gopen
- Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | - Stephen Tenn
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Isaac Yang
- Department of Neurosurgery, University of California Los Angeles, Los Angeles, USA.
- Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, CA, USA.
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA.
- Ronald Reagan UCLA Medical Center, David Geffen School of Medicine at UCLA, UCLA Jonsson Comprehensive Cancer Center, 300 Stein Plaza, Ste. 562, 5th Floor Wasserman Bldg., Los Angeles, CA, 900-95-6901, USA.
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Stereotactic radiosurgery and radiotherapy for acoustic neuromas. Neurosurg Rev 2019; 43:941-949. [DOI: 10.1007/s10143-019-01103-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/06/2019] [Accepted: 04/05/2019] [Indexed: 10/27/2022]
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Choi Y, Kim S, Kwak DW, Lee HS, Kang MK, Lee DK, Hur WJ. Maximum diameter versus volumetric assessment for the response evaluation of vestibular schwannomas receiving stereotactic radiotherapy. Radiat Oncol J 2018; 36:114-121. [PMID: 29983031 PMCID: PMC6074071 DOI: 10.3857/roj.2018.00031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 05/10/2018] [Indexed: 11/17/2022] Open
Abstract
Purpose To explore the feasibility of maximum diameter as a response assessment method for vestibular schwannomas (VS) after stereotactic radiosurgery or fractionated stereotactic radiotherapy (RT), we analyzed the concordance of RT responses between maximum diameters and volumetric measurements. Materials and Methods Forty-two patients receiving curative stereotactic radiosurgery or fractionated stereotactic RT for VS were analyzed retrospectively. Twelve patients were excluded: 4 did not receive follow-up magnetic resonance imaging (MRI) scans and 8 had initial MRI scans with a slice thickness >3 mm. The maximum diameter, tumor volume (TV), and enhanced tumor volume (ETV) were measured in each MRI study. The percent change after RT was evaluated according to the measurement methods and their concordances were calculated with the Pearson correlation. The response classifications were determined by the assessment modalities, and their agreement was analyzed with Cohen kappa statistics. Results Median follow-up was 31.0 months (range, 3.5 to 86.5 months), and 90 follow-up MRI studies were analyzed. The percent change of maximum diameter correlated strongly with TV and ETV (r(p) = 0.85, 0.63, p = 0.000, respectively). Concordance of responses between the Response Evaluation Criteria in Solid Tumors (RECIST) using the maximum diameters and either TV or ETV were moderate (kappa = 0.58; 95% confidence interval, 0.32-0.85) or fair (kappa = 0.32; 95% confidence interval, 0.05-0.59), respectively. Conclusion The percent changes in maximum diameter and the responses in RECIST were significantly concordant with those in the volumetric measurements. Therefore, the maximum diameters can be used for the response evaluation of VS following stereotactic RT.
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Affiliation(s)
- Youngmin Choi
- Department of Radiation Oncology, Dong-A University College of Medicine, Busan, Korea
| | - Sungmin Kim
- Department of Radiation Oncology, Dong-A University College of Medicine, Busan, Korea
| | - Dong-Won Kwak
- Department of Radiation Oncology, Dong-A University College of Medicine, Busan, Korea
| | - Hyung-Sik Lee
- Department of Radiation Oncology, Dong-A University College of Medicine, Busan, Korea
| | - Myung-Koo Kang
- Department of Otolaryngology-Head and Neck Surgery, Dong-A University College of Medicine, Busan, Korea
| | - Dong-Kun Lee
- Department of Otolaryngology-Head and Neck Surgery, Dong-A University College of Medicine, Busan, Korea
| | - Won-Joo Hur
- Department of Radiation Oncology, Dong-A University College of Medicine, Busan, Korea
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Five-year outcomes following hypofractionated stereotactic radiotherapy delivered in five fractions for acoustic neuromas: the mean cochlear dose may impact hearing preservation. Int J Clin Oncol 2018; 23:608-614. [DOI: 10.1007/s10147-018-1267-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 03/14/2018] [Indexed: 02/01/2023]
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13
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Sager O, Beyzadeoglu M, Dincoglan F, Demiral S, Uysal B, Gamsiz H, Oysul K, Dirican B, Sirin S. Management of Vestibular Schwannomas with Linear Accelerator-Based Stereotactic Radiosurgery: A Single Center Experience. TUMORI JOURNAL 2018; 99:617-22. [DOI: 10.1177/030089161309900510] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aims and background The primary goal of treatment for vestibular schwannoma is to achieve local control without comprimising regional cranial nerve function. Stereotactic radiosurgery has emerged as a viable therapeutic option for vestibular schwannoma. The aim of the study is to report our 15-year single center experience using linear accelerator-based stereotactic radiosurgery in the management of patients with vestibular schwannoma. Methods and study design Between July 1998 and January 2013, 68 patients with unilateral vestibular schwannoma were treated using stereotactic radiosurgery at the Department of Radiation Oncology, Gulhane Military Medical Academy. All patients underwent high-precision stereotactic radiosurgery using a linear accelerator with 6-MV photons. Results Median follow-up time was 51 months (range, 9–107). Median age was 45 years (range, 20–77). Median dose was 12 Gy (range, 10–13) prescribed to the 85%-95% isodose line encompassing the target volume. Local tumor control in patients with periodic follow-up imaging was 96.1%. Overall hearing preservation rate was 76.5%. Conclusions Linear accelerator-based stereotactic radiosurgery offers a safe and effective treatment for patients with vestibular schwannoma by providing high local control rates along with improved quality of life through well-preserved hearing function.
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Affiliation(s)
- Omer Sager
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Murat Beyzadeoglu
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Ferrat Dincoglan
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Selcuk Demiral
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Bora Uysal
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Hakan Gamsiz
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Kaan Oysul
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Bahar Dirican
- Department of Radiation Oncology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Sait Sirin
- Department of Neurosurgery, Gulhane Military Medical Academy, Ankara, Turkey
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Mehta RP, Cueva RA, Brown JD, Fliss DM, Gil Z, Kassam AB, Rassekh CH, Schlosser RJ, Snyderman CH, Har-El G. What's New in Skull Base Medicine and Surgery? Skull Base Committee Report. Otolaryngol Head Neck Surg 2016; 135:620-30. [PMID: 17011428 DOI: 10.1016/j.otohns.2006.04.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Accepted: 04/27/2006] [Indexed: 11/28/2022]
Affiliation(s)
- Ritvik P Mehta
- American Academy of Otolaryngology-Head and Neck Surgery, Alexandria, Virginia, USA
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Bahig H, Simard D, Létourneau L, Wong P, Roberge D, Filion E, Donath D, Sahgal A, Masucci L. A Study of Pseudoprogression After Spine Stereotactic Body Radiation Therapy. Int J Radiat Oncol Biol Phys 2016; 96:848-856. [PMID: 27788956 DOI: 10.1016/j.ijrobp.2016.07.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/18/2022]
Abstract
PURPOSE To determine the incidence of pseudoprogression (PP) after spine stereotactic body radiation therapy based on a detailed and quantitative assessment of magnetic resonance imaging (MRI) morphologic tumor alterations, and to identify predictive factors distinguishing PP from local recurrence (LR). METHODS AND MATERIALS A retrospective analysis of 35 patients with 49 spinal segments treated with spine stereotactic body radiation therapy, from 2009 to 2014, was conducted. The median number of follow-up MRI studies was 4 (range, 2-7). The gross tumor volumes (GTVs) within each of the 49 spinal segments were contoured on the pretreatment and each subsequent follow-up T1- and T2-weighted MRI sagittal sequence. T2 signal intensity was reported as the mean intensity of voxels constituting each volume. LR was defined as persistent GTV enlargement on ≥2 serial MRI studies for ≥6 months or on pathologic confirmation. PP was defined as a GTV enlargement followed by stability or regression on subsequent imaging within 6 months. Kaplan-Meier analysis was used for estimation of actuarial local control, disease-free survival, and overall survival. RESULTS The median follow-up was 23 months (range, 1-39 months). PP was identified in 18% of treated segments (9 of 49) and LR in 29% (14 of 49). Earlier volume enlargement (5 months for PP vs 15 months for LR, P=.005), greater GTV to reference nonirradiated vertebral body T2 intensity ratio (+30% for PP vs -10% for LR, P=.005), and growth confined to 80% of the prescription isodose line (80% IDL) (8 of 9 PP cases vs 1 of 14 LR cases, P=.002) were associated with PP on univariate analysis. Multivariate analysis confirmed an earlier time to volume enlargement and growth within the 80% IDL as significant predictors of PP. LR involved the epidural space in all but 1 lesion, whereas PP was confined to the vertebral body in 7 of 9 cases. CONCLUSIONS PP was observed in 18% of treated spinal segments. Tumor growth confined to the 80% IDL and earlier time to tumor enlargement were predictive for PP.
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Affiliation(s)
- Houda Bahig
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Dany Simard
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Laurent Létourneau
- Department of Radiology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Philip Wong
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - David Roberge
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Edith Filion
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - David Donath
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada
| | - Arjun Sahgal
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Laura Masucci
- Department of Radiation Oncology, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec, Canada.
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Surgical management of vestibular schwannomas after failed radiation treatment. Neurosurg Rev 2016; 39:303-12; discussion 312. [DOI: 10.1007/s10143-015-0690-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 10/31/2015] [Indexed: 12/28/2022]
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17
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3D quantitative assessment of response to fractionated stereotactic radiotherapy and single-session stereotactic radiosurgery of vestibular schwannoma. Eur Radiol 2015; 26:849-57. [PMID: 26139318 DOI: 10.1007/s00330-015-3895-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 05/19/2015] [Accepted: 06/16/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To determine clinical outcome of patients with vestibular schwannoma (VS) after treatment with fractionated stereotactic radiotherapy (FSRT) and single-session stereotactic radiosurgery (SRS) by using 3D quantitative response assessment on MRI. MATERIALS This retrospective analysis included 162 patients who underwent radiation therapy for sporadic VS. Measurements on T1-weighted contrast-enhanced MRI (in 2-year post-therapy intervals: 0-2, 2-4, 4-6, 6-8, 8-10, 10-12 years) were taken for total tumour volume (TTV) and enhancing tumour volume (ETV) based on a semi-automated technique. Patients were considered non-responders (NRs) if they required subsequent microsurgical resection or developed radiological progression and tumour-related symptoms. RESULTS Median follow-up was 4.1 years (range: 0.4-12.0). TTV and ETV decreased for both the FSRT and SRS groups. However, only the FSRT group achieved significant tumour shrinkage (p < 0.015 for TTV, p < 0.005 for ETV over time). The 11 NRs showed proportionally greater TTV (median TTV pre-treatment: 0.61 cm(3), 8-10 years after: 1.77 cm(3)) and ETV despite radiation therapy compared to responders (median TTV pre-treatment: 1.06 cm(3); 10-12 years after: 0.81 cm(3); p = 0.001). CONCLUSION 3D quantification of VS showed a significant decrease in TTV and ETV on FSRT-treated patients only. NR had significantly greater TTV and ETV over time. KEY POINTS Only FSRT not GK-treated patients showed significant tumour shrinkage over time. Clinical non-responders showed significantly less tumour shrinkage when compared to responders. 3D volumetric assessment of vestibular schwannoma shows advantages over unidimensional techniques.
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Ellenbogen JR, Waqar M, Kinshuck AJ, Jenkinson MD, Lesser THJ, Husband D, Javadpour M. Linear accelerator radiosurgery for vestibular schwannomas: Results of medium-term follow-up. Br J Neurosurg 2015; 29:678-84. [PMID: 25968327 DOI: 10.3109/02688697.2015.1036837] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND To examine tumour control, via volume changes, and the complications of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) treatment of vestibular schwannomas (VSs) on medium-term follow-up. METHODS Between September 2003 and November 2009 fifty consecutive patients with VSs treated with SRS using a marginal dose of 12.5 Gy utilizing a LINAC equipped with a micro-multileaf collimator were identified. Evaluation included serial magnetic resonance imaging (MRI), and neurological and hearing examinations. RESULTS The median tumour volume at treatment was 2.4 (range: 0.24-10.59) cm3. The intracranial diameter of the tumours ranged between 7.7 and 28.7 (median: 15.8) mm. Follow-up MRI was available for analysis on 49 patients. The median radiological follow-up period was 5.8 (range: 1.4-9.2) years. The median tumour volume at last follow-up was 1.1 (range: 0.03-5.3) cm3. VS decreased in size in 45 (90%) patients, with a median reduction in tumour volume of 1.46 (range: 0.06-9.29) cm3 or a median tumour size reduction of 59% of the baseline (range: 6-90%) in these patients. VS remained stable in 2 patients and increased in size in 2 patients. Only 1 patient (2%) required additional intervention (surgery). 15 patients had useful hearing pre-treatment; 10 post-treatment pure-tone audiograms of these patients were available. 5 (50%) patients still had useful hearing post treatment. Non-auditory adverse radiation effects included new (House-Brackmann grade II) or worsened facial nerve palsy (House-Brackmann grade II to grade V) in 2 (4%) patients and trigeminal sensory disturbance in 2 (4%) patients. CONCLUSIONS At medium term, the vast majority of VSs treated with LINAC-based SRS exhibit tumour shrinkage. The slightly higher rate of facial nerve palsy compared with Gamma Knife surgery (GKS) results may be related to the learning curve. Other complications were similar to reported GKS results for VSs of comparable sizes.
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Affiliation(s)
- Jonathan R Ellenbogen
- a Department of Neurosurgery , The Walton Centre for Neurology & Neurosurgery NHS Foundation Trust , Liverpool , UK
| | - Mueez Waqar
- b School of Medicine, University of Liverpool , Liverpool , UK.,c Institute of Ageing and Chronic disease, University of Liverpool , Liverpool , UK
| | - Andrew J Kinshuck
- d Department of Otolaryngology and Head & Neck Surgery , Aintree University Hospitals NHS Foundation Trust, Longmoor Lane , Liverpool , UK
| | - Michael D Jenkinson
- a Department of Neurosurgery , The Walton Centre for Neurology & Neurosurgery NHS Foundation Trust , Liverpool , UK.,c Institute of Ageing and Chronic disease, University of Liverpool , Liverpool , UK
| | - Tristram H J Lesser
- d Department of Otolaryngology and Head & Neck Surgery , Aintree University Hospitals NHS Foundation Trust, Longmoor Lane , Liverpool , UK
| | - David Husband
- e Clatterbridge Cancer Centre NHS Foundation Trust , Wirral , UK
| | - Mohsen Javadpour
- f Department of Neurosurgery , Beaumont Hospital , Dublin 9 , Ireland
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Matsuo T, Okunaga T, Kamada K, Izumo T, Hayashi N, Nagata I. Long-term follow-up results of linear accelerator-based radiosurgery for vestibular schwannoma using serial three-dimensional spoiled gradient-echo MRI. J Clin Neurosci 2015; 22:320-5. [DOI: 10.1016/j.jocn.2014.06.100] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/10/2014] [Indexed: 11/26/2022]
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20
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Badakhshi H, Muellner S, Wiener E, Budach V. Image-guided stereotactic radiotherapy for patients with vestibular schwannoma. A clinical study. Strahlenther Onkol 2014; 190:533-7. [PMID: 24589920 DOI: 10.1007/s00066-014-0646-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 11/18/2013] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Local tumor control and functional outcome after linac-based stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) for vestibular schwannoma (VS) were assessed. METHODS In all, 250 patients with VS were treated: 190 patients with tumors < 2 cm diameter underwent SRS and 60 patients with tumors >2 to 3.5 cm underwent FSRT. Dose prescription for all cases with SRS (n = 190, 76 %) was 13.5 Gy. For FSRT, mainly two hypofractionated schedules (n = 60, 24 %) with either 7 fractions of 5 Gy (total dose: 35 Gy; n = 35) or 11 fractions of 3.8 Gy (total dose: 41.8 Gy; n = 16) were used. The primary endpoint was local tumor control. Secondary endpoints were symptomatic control and morbidity. RESULTS The median follow-up was 33.8 months. The 3-year local tumor control was 88.9 %. Local control for SRS and FSRT was 88 and 92 %, respectively. For FSRT with 35 and 41.8 Gy, local control was 90 and 100 %, respectively. There were no acute reactions exceeding grade I. In 61 cases (24.4 % of the entire cohort), trigeminal neuralgia was reported prior to treatment. At last follow-up, 16.3 % (10/61) of those patients reported relief of pain. Regarding facial nerve dysfunction, 45 patients (18 %) presented with symptoms prior to RT. At the last follow-up, 13.3% (6/45) of those patients reported a relief of dysesthesia. CONCLUSION Using SRS to treat small VS results in good local control rates. FSRT for larger lesions also seems effective. Severe treatment-related complications are not frequent. Therefore, image-guided stereotactic radiotherapy is an appropriate alternative to microsurgery for patients with VS.
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Affiliation(s)
- H Badakhshi
- Departments for Radiation Oncology, Charité School of Medicine and University Hospital of Berlin, Augustenburger Platz 1, 13353, Berlin, Germany,
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Badakhshi H, Graf R, Böhmer D, Synowitz M, Wiener E, Budach V. Results for local control and functional outcome after linac-based image-guided stereotactic radiosurgery in 190 patients with vestibular schwannoma. JOURNAL OF RADIATION RESEARCH 2014; 55:288-292. [PMID: 23979079 PMCID: PMC3951065 DOI: 10.1093/jrr/rrt101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 07/07/2013] [Accepted: 07/18/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND We assessed local control (LC) and functional outcome after linac-based stereotactic radiosurgery (SRS) for vestibular schwannoma (VS). METHODS Between 1998 and 2008, 190 patients with VS were treated with SRS. All patients had tumors <2 cm diameter. Patients received 13.5 Gy prescribed to the 80th isodose at the tumor margin. The primary endpoint was LC. Secondary endpoints were symptomatic control and morbidity. RESULTS Median follow-up was 40 months. LC was achieved in 88% of patients. There were no acute reactions exceeding Grade I. Trigeminal nerve dysfunction was present in 21.6% (n = 41) prior to SRS. After treatment, 85% (n = 155) had no change, 4.4,% (n = 8) had a relief of symptoms, 10.4% (n = 19) had new symptoms. Facial nerve dysfunction was present in some patients prior to treatment, e.g. paresis (12.6%; n = 24) and dysgeusia (0.5%; n = 1). After treatment 1.1% (n = 2) reported improvement and 6.1% (n = 11) experienced new symptoms. Hearing problems before SRS were present in 69.5% of patients (n = 132). After treatment, 62.6% (n = 144) had no change, 10.4% (n = 19) experienced improvement and 26.9% (n = 49) became hearing impaired. CONCLUSION This series of SRS for small VS provided similar LC rates to microsurgery; thus, it is effective as a non-invasive, image-guided procedure. The functional outcomes observed indicate the safety and effectiveness of linac-based SRS. Patients may now be informed of the clinical equivalence of SRS to microsurgery.
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Affiliation(s)
- Harun Badakhshi
- Departments for Radiation Oncology, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Reinhold Graf
- Departments for Radiation Oncology, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Dirk Böhmer
- Departments for Radiation Oncology, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Michael Synowitz
- Department for Neurosurgery, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Edzard Wiener
- Institute for Neuroradiology, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Volker Budach
- Departments for Radiation Oncology, Charité University Medicine Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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Treatment Outcomes in Patients Treated With CyberKnife Radiosurgery for Vestibular Schwannoma. Otol Neurotol 2014; 35:162-70. [DOI: 10.1097/mao.0b013e3182a435f5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Nonaka Y, Fukushima T, Watanabe K, Friedman AH, Sampson JH, Mcelveen JT, Cunningham CD, Zomorodi AR. Contemporary surgical management of vestibular schwannomas: analysis of complications and lessons learned over the past decade. Neurosurgery 2013; 72:ons103-15; discussion ons115. [PMID: 23037828 DOI: 10.1227/neu.0b013e3182752b05] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Despite advanced microsurgical techniques, more refined instrumentation, and expert team management, there is still a significant incidence of complications in vestibular schwannoma surgery. OBJECTIVE To analyze complications from the microsurgical treatment of vestibular schwannoma by an expert surgical team and to propose strategies for minimizing such complications. METHODS Surgical outcomes and complications were evaluated in a consecutive series of 410 unilateral vestibular schwannomas treated from 2000 to 2009. Clinical status and complications were assessed postoperatively (within 7 days) and at the time of follow-up (range, 1-116 months; mean, 32.7 months). RESULTS Follow-up data were available for 357 of the 410 patients (87.1%). Microsurgical tumor resection was performed through a retrosigmoid approach in 70.7% of cases. Thirty-three patients (8%) had intrameatal tumors and 204 (49.8%) had tumors that were <20 mm. Gross total resection was performed in 306 patients (74.6%). Hearing preservation surgery was attempted in 170 patients with tumors <20 mm, and good hearing was preserved in 74.1%. The main neurological complication was facial palsy (House-Brackmann grade III-VI), observed in 14% of patients (56 cases) postoperatively; however, 59% of them improved during the follow-up period. Other neurological complications were disequilibrium in 6.3%, facial numbness in 2.2%, and lower cranial nerve deficit in 0.5%. Nonneurological complications included cerebrospinal fluid leaks in 7.6%, wound infection in 2.2%, and meningitis in 1.7%. CONCLUSION Many of these complications are avoidable through further refinement of operative technique, and strategies for avoiding complications are proposed.
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Affiliation(s)
- Yoichi Nonaka
- Division of Neurosurgery, Duke University Medical Center, Durham, North Carolina, USA.
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Ujifuku K, Matsuo T, Toyoda K, Baba S, Okunaga T, Hayashi Y, Kamada K, Morikawa M, Suyama K, Nagata I, Hayashi N. Repeated delayed onset cerebellar radiation injuries after linear accelerator-based stereotactic radiosurgery for vestibular schwannoma: case report. Neurol Med Chir (Tokyo) 2013; 52:933-6. [PMID: 23269054 DOI: 10.2176/nmc.52.933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A 63-year-old woman presented with right hearing disturbance and vertigo. Magnetic resonance (MR) imaging revealed the presence of right vestibular schwannoma (VS). Stereotactic radiosurgery (SRS) was performed with a tumor marginal dose of 14 Gy using two isocenters. She was followed up clinically and neuroradiologically using three-dimensional spoiled gradient-echo MR imaging. She experienced temporal neurological deterioration due to peritumoral edema in her right cerebellar peduncle and pons for a few months beginning 1.5 years after SRS, when she experienced transient right facial dysesthesia and hearing deterioration. Ten years after SRS, the patient presented with sudden onset of vertigo, gait disturbance, diplopia, dysarthria, and nausea. MR imaging demonstrated a new lesion in the right cerebellar peduncle, which was diagnosed as radiation-induced stroke. The patient was followed up conservatively and her symptoms disappeared within a few months. Multiple delayed onset radiation injuries are possible sequelae of SRS for VS.
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Affiliation(s)
- Kenta Ujifuku
- Department of Neurosurgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki
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Ruzevick J, Kleinberg L, Rigamonti D. Imaging changes following stereotactic radiosurgery for metastatic intracranial tumors: differentiating pseudoprogression from tumor progression and its effect on clinical practice. Neurosurg Rev 2013; 37:193-201; discussion 201. [PMID: 24233257 DOI: 10.1007/s10143-013-0504-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 08/18/2013] [Accepted: 08/24/2013] [Indexed: 02/07/2023]
Abstract
Stereotactic radiosurgery has become standard adjuvant treatment for patients with metastatic intracranial lesions. There has been a growing appreciation for benign imaging changes following radiation that are difficult to distinguish from true tumor progression. These imaging changes, termed pseudoprogression, carry significant implications for patient management. In this review, we discuss the current understanding of pseudoprogression in metastatic brain lesions, research to differentiate pseudoprogression from true progression, and clinical implications of pseudoprogression on treatment decisions.
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Affiliation(s)
- Jacob Ruzevick
- Department of Neurological Surgery, The Johns Hopkins University School of Medicine, Phipps Building, Room 126, 600 N. Wolfe Street, Baltimore, MD, 21287, USA,
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Microsurgery versus stereotactic radiation for small vestibular schwannomas: a meta-analysis of patients with more than 5 years' follow-up. Otol Neurotol 2013; 33:1611-20. [PMID: 22996165 DOI: 10.1097/mao.0b013e31826dbd02] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the long-term outcome of hearing and tumor outcome of small vestibular schwannomas treated with stereotactic radiation and microsurgery. DATA SOURCES A thorough search for English-language publications and "in process" articles dating from 1948 to December 2011 was conducted using Ovid MEDLINE. STUDY SELECTION The principal criteria were patients having had microsurgery or radiation therapy as their sole treatment, with a follow-up of at least 5 years, and a useful hearing level at diagnosis. DATA EXTRACTION Sixteen studies met our criteria. Hearing preservation outcome (worse or preserved) and tumor outcome (failure, control) data, as well as all other significant observations, were collected from the articles. Stereotactic radiation was the only radiation therapy analyzed. DATA SYNTHESIS The Pearson χ test was our primary statistical analysis. CONCLUSION Stereotactic radiation showed significantly better long-term hearing preservation outcome rates than microsurgery (p < 0.001). However, long-term tumor outcome was not significantly different in stereotactic radiation as compared with microsurgery (p = 0.122). Although stereotactic radiation demonstrates a more favorable long-term hearing preservation outcome as compared with microsurgery, additional studies are required to provide the medical field with a better understanding of vestibular schwannoma treatment.
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Follow-up MR findings of spinal foraminal nerve sheath tumors after stereotactic irradiation. Jpn J Radiol 2012; 31:192-6. [DOI: 10.1007/s11604-012-0169-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 11/21/2012] [Indexed: 01/04/2023]
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van de Langenberg R, Dohmen AJ, de Bondt BJ, Nelemans PJ, Baumert BG, Stokroos RJ. Volume Changes After Stereotactic LINAC Radiotherapy in Vestibular Schwannoma: Control Rate and Growth Patterns. Int J Radiat Oncol Biol Phys 2012; 84:343-9. [DOI: 10.1016/j.ijrobp.2011.12.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 08/13/2011] [Accepted: 12/06/2011] [Indexed: 01/09/2023]
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Hearing preservation after LINAC radiosurgery and LINAC radiotherapy for vestibular schwannoma. J Clin Neurosci 2012; 19:1065-70. [DOI: 10.1016/j.jocn.2012.01.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 01/19/2012] [Indexed: 11/24/2022]
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Walz PC, Bush ML, Robinett Z, Kirsch CFE, Welling DB. Three-Dimensional Segmented Volumetric Analysis of Sporadic Vestibular Schwannomas. Otolaryngol Head Neck Surg 2012; 147:737-43. [DOI: 10.1177/0194599812447766] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Objective To compare 3-D segmented volumetric analysis of vestibular schwannomas (VS) with traditional linear tumor measurement on serial magnetic resonance imaging (MRI) studies to assess volume and growth rates. Study Design Case series with retrospective chart review. Setting Tertiary care medical center. Methods This analysis identified 24 VS patients clinically followed with serial gadolinium enhanced images. Maximum linear dimensions (MLD) were obtained from gadolinium-contrasted T1 sequences from 3 serial MRI scans per RECIST guidelines. MLD was cubed (MLD3) and orthogonal analysis (OA) was carried out to provide volumetric estimates for comparison with segmented data. Segmented volumetric analysis (SVA) was performed with semi-automated 3-D conformal procedure. Tumor volume, percentage change in volume, and interval percentage change were compared using paired 2-tailed t tests. Results The average interval between MRIs was 2.6 years. Volume estimates differed significantly between SVA and OA and MLD3 at all intervals. Linear growth measurements averaged 0.5 mm/y (5.4%). Volumetric growth was 50 mm3/y (22.8%) with SVA, 110 mm3/y (19.6%) with OA, and 210 mm3/y (14.4%) with MLD3 estimates. Differences between MLD and both MLD3 and SVA were significant, but significance between MLD3 and SVA was only identified in interval analysis. Progression was identified in 75% more patients with SVA than OA, MLD3, or MLD. Conclusions VS assume complex configurations. Linear measurements inaccurately estimate tumor volume and growth compared with segmented analysis. SVA is a useful clinical tool that accurately assesses tumor volume. Use of outcomes such as tumor volume and percentage of volume change may be more sensitive in assessing tumor progression compared with linear measurements.
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Affiliation(s)
- Patrick C. Walz
- Department of Otolaryngology–Head and Neck Surgery, The Ohio State University, Columbus, Ohio, USA
| | - Matthew L. Bush
- Department of Otolaryngology–Head and Neck Surgery, The Ohio State University, Columbus, Ohio, USA
- Department of Otolaryngology Head and Neck Surgery; Dr Bush recently relocated to the University of Kentucky, Lexington, Kentucky, USA
| | - Zachary Robinett
- School of Medicine, The Ohio State University, Columbus, Ohio, USA
| | | | - D. Bradley Welling
- Department of Otolaryngology–Head and Neck Surgery, The Ohio State University, Columbus, Ohio, USA
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Hayhurst C, Zadeh G. Tumor pseudoprogression following radiosurgery for vestibular schwannoma. Neuro Oncol 2011; 14:87-92. [PMID: 22028389 DOI: 10.1093/neuonc/nor171] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We sought to characterize vestibular schwannoma (VS) pseudoprogression after radiosurgery to assess its incidence, causative factors, and association with radiation-induced adverse effects. We performed a retrospective study of VS treated with Gamma Knife radiosurgery during 2005-2009. Seventy-five patients had at least 24 months of clinical and radiographic follow-up (median, 29 months) and were included. Tumor response was calculated volumetrically using Gamma plan software on consecutive MRIs. All treatment plans were reviewed for dosimetry characteristics. Forty-nine VS (65%) were stable or regressed after treatment. Seventeen (23%) underwent pseudoprogression, with onset of enlargement at 6 months. Seven (9%) remained larger than initial treatment volume at last follow-up. Nine (12%) had persistent growth. Three patients underwent subsequent microsurgery. One patient required intervention at 3 months for cystic enlargement; otherwise, all patients with progressive enlargement had stable VS until at least 24 months. Twenty-six patients (34.7%) developed nonauditory adverse radiation effects after treatment, including cranial neuropathy, ataxia, and hydrocephalus. There was no statistical association between onset of clinical deterioration and tumor response. Volume changes in the first 24 months after radiosurgery rarely herald treatment failure. Any volume change after 24 months is indicative of treatment failure. Pseudoprogression does not appear to be independently linked to radiation-induced morbidity, and there are no patient-related or radiosurgical parameters that predict tumor response.
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van de Langenberg R, Hanssens PEJ, van Overbeeke JJ, Verheul JB, Nelemans PJ, de Bondt BJ, Stokroos RJ. Management of large vestibular schwannoma. Part I. Planned subtotal resection followed by Gamma Knife surgery: radiological and clinical aspects. J Neurosurg 2011; 115:875-84. [PMID: 21838510 DOI: 10.3171/2011.6.jns101958] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT In large vestibular schwannoma (VS), microsurgery is the main treatment option, and complete resection is considered the primary goal. However, previous studies have documented suboptimal facial nerve outcomes in patients who undergo complete resection of large VSs. Subtotal resection is likely to reduce the risk of facial nerve injury but increases the risk of lesion regrowth. Gamma Knife surgery (GKS) can be performed to achieve long-term growth control of residual VS after incomplete resection. In this study the authors report on the results in patients treated using planned subtotal resection followed by GKS with special attention to volumetric growth, control rate, and symptoms. METHODS Fifty consecutive patients who underwent the combined treatment strategy of subtotal microsurgical removal and GKS for large VSs between 2002 and 2009 were retrospectively analyzed. Patients with neurofibromatosis Type 2 were excluded. Patient charts were reviewed for clinical symptoms. Audiograms were evaluated to classify hearing pre- and postoperatively. Preoperative and follow-up contrast-enhanced T1-weighted MR images were analyzed using volume-measuring software. RESULTS Surgery was performed via a translabyrinthine (25 patients) or retrosigmoid (25 patients) approach. The median follow-up was 33.8 months. Clinical control was achieved in 92% of the cases and radiological control in 90%. One year after radiosurgery, facial nerve function was good (House-Brackmann Grade I or II) in 94% of the patients. One of the two patients who underwent surgery to preserve hearing maintained serviceable hearing after resection followed by GKS. CONCLUSIONS Considering the good tumor growth control and facial nerve function preservation as well as the possibility of preserving serviceable hearing and the low number of complications, subtotal resection followed by GKS can be the treatment option of choice for large VSs.
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Affiliation(s)
- Rick van de Langenberg
- Departments of Otolaryngology, Head and Neck Surgery, Maastricht University, Maastricht, The Netherlands.
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van de Langenberg R, Hanssens PEJ, Verheul JB, van Overbeeke JJ, Nelemans PJ, Dohmen AJC, de Bondt BJ, Stokroos RJ. Management of large vestibular schwannoma. Part II. Primary Gamma Knife surgery: radiological and clinical aspects. J Neurosurg 2011; 115:885-93. [PMID: 21838503 DOI: 10.3171/2011.6.jns101963] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT In large vestibular schwannomas (VSs), microsurgery is the main treatment option. A wait-and-scan policy or radiosurgery are generally not recommended given concerns of further lesion growth or increased mass effect due to transient swelling. Note, however, that some patients do not present with symptomatic mass effect or may still have serviceable hearing. Moreover, others may be old, suffer from severe comorbidity, or refuse any surgery. In this study the authors report the results in patients with large, growing VSs primarily treated with Gamma Knife surgery (GKS), with special attention to volumetric growth, control rate, and symptoms. METHODS The authors retrospectively analyzed 33 consecutive patients who underwent GKS for large, growing VSs, which were defined as > 6 cm(3) and at least indenting the brainstem. Patients with neurofibromatosis Type 2 were excluded from analysis, as were patients who had undergone previous treatment. Volume measurements were performed on contrast-enhanced T1-weighted MR images at the time of GKS and during follow-up. Medical charts were analyzed for clinical symptoms. RESULTS Radiological growth control was achieved in 88% of cases, clinical control (that is, no need for further treatment) in 79% of cases. The median follow-up was 30 months, and the mean VS volume was 8.8 cm(3) (range 6.1-17.7 cm(3)). No major complications occurred, although ventriculoperitoneal shunts were placed in 2 patients. The preservation of serviceable hearing and facial and trigeminal nerve function was achieved in 58%, 91%, and 86% of patients, respectively, with any facial and trigeminal neuropathy being transient. In 92% of the patients presenting with trigeminal hypesthesia before GKS, the condition resolved during follow-up. No patient- or VS-related feature was correlated with growth. CONCLUSIONS Primary GKS for large VSs leads to acceptable radiological growth rates and clinical control rates, with the chance of hearing preservation. Although a higher incidence of clinical control failure and postradiosurgical morbidity is noted, as compared with that for smaller VSs, primary radiosurgery is suitable for a selected group of patients. The absence of symptomatology due to mass effect on the brainstem or cerebellum is essential, as are close clinical and radiological follow-ups, because there is little reserve for growth or swelling.
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Affiliation(s)
- Rick van de Langenberg
- Departments of Otolaryngology, Head and Neck Surgery, Maastricht University MedicalCentre, The Netherlands.
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Powell C, Micallef C, Gonsalves A, Wharram B, Ashley S, Brada M. Fractionated Stereotactic Radiotherapy in the Treatment of Vestibular Schwannoma (Acoustic Neuroma): Predicting the Risk of Hydrocephalus. Int J Radiat Oncol Biol Phys 2011; 80:1143-50. [DOI: 10.1016/j.ijrobp.2010.04.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 03/30/2010] [Accepted: 04/01/2010] [Indexed: 10/19/2022]
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Whitmore RG, Urban C, Church E, Ruckenstein M, Stein SC, Lee JYK. Decision analysis of treatment options for vestibular schwannoma. J Neurosurg 2011; 114:400-13. [DOI: 10.3171/2010.3.jns091802] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Widespread use of MR imaging has contributed to the more frequent diagnosis of vestibular schwannomas (VSs). These tumors represent 10% of primary adult intracranial neoplasms, and if they are symptomatic, they usually present with hearing loss and tinnitus. Currently, there are 3 treatment options for quality of life (QOL): wait and scan, microsurgery, and radiosurgery. In this paper, the authors' purpose is to determine which treatment modality yields the highest QOL at 5- and 10-year follow-up, considering the likelihood of recurrence and various complications.
Methods
The MEDLINE, Embase, and Cochrane online databases were searched for English-language articles published between 1990 and June 2008, containing key words relating to VS. Data were pooled to calculate the prevalence of treatment complications, tumor recurrence, and QOL with various complications. For parameters in which incidence varied with time of follow-up, the authors used meta-regression to determine the mean prevalence rates at a specified length of follow-up. A decision-analytical model was constructed to compare 5- and 10-year outcomes for a patient with a unilateral tumor and partially intact hearing. The 3 treatment options, wait and scan, microsurgery, and radiosurgery, were compared.
Results
After screening more than 2500 abstracts, the authors ultimately included 113 articles in this analysis. Recurrence, complication rates, and onset of complication varied with the treatment chosen. The relative QOL at the 5-year follow-up was 0.898 of normal for wait and scan, 0.953 for microsurgery, and 0.97 for radiosurgery. These differences are significant (p < 0.0052). Data were too scarce at the 10-year follow-up to calculate significant differences between the microsurgery and radiosurgery strategies.
Conclusions
At 5 years, patients treated with radiosurgery have an overall better QOL than those treated with either microsurgery or those investigated further with serial imaging. The authors found that the complications associated with wait-and-scan and microsurgery treatment strategies negatively impacted patient lives more than the complications from radiosurgery. One limitation of this study is that the 10-year follow-up data were too limited to analyze, and more studies are needed to determine if the authors' results are still consistent at 10 years.
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Affiliation(s)
| | | | | | - Michael Ruckenstein
- 2Otorhinolaryngology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
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Stereotactic radiosurgery: a meta-analysis of current therapeutic applications in neuro-oncologic disease. J Neurooncol 2010; 103:1-17. [DOI: 10.1007/s11060-010-0360-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 08/09/2010] [Indexed: 10/18/2022]
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Sakanaka K, Mizowaki T, Arakawa Y, Araki N, Oya N, Takahashi JA, Mikuni N, Miyamoto S, Hashimoto N, Hiraoka M. Hypofractionated stereotactic radiotherapy for acoustic neuromas: safety and effectiveness over 8 years of experience. Int J Clin Oncol 2010; 16:27-32. [PMID: 20830603 DOI: 10.1007/s10147-010-0122-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 08/08/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Little information is available about long-term outcomes of hypofractionated stereotactic radiotherapy (hypo-FSRT) for acoustic neuromas. In this study, the safety and effectiveness of hypo-FSRT for unilateral acoustic neuroma were reviewed over 8 years of experience at our institution. METHODS Between May 1998 and October 2006, 27 patients were consecutively treated by linear accelerator-based hypo-FSRT. Two patients were excluded from this study because they were lost to follow-up within 12 months. The median follow-up period for the rest was 59 (range 24-133) months. Two types of treatment schedules were adopted. Thirteen patients received 30-39 Gy, given in 10-13 fractions (regimen A), whereas after July 2003, 12 patients received 20-24 Gy, given in 5-6 fractions at the tumor periphery (regimen B). These treatments were scheduled to be delivered in three fractions per week (Monday, Wednesday, Friday). The median planning target volume was 2.0, with 1.7 ml (range 0.7-10.6) in regimen A and 5.2 ml (range 0.9-9.3) in regimen B. In the pretreatment audiogram, seven patients (two in regimen A and five in regimen B) had serviceable hearing (Gardner-Robertson Class I-II). RESULTS Local control rates were 100% with regimen A and 92% with regimen B. Serviceable hearing was preserved in four of five patients in regimen B but no patients in regimen A at the last follow-up. No permanent facial or trigeminal nerve morbidity was observed following treatment, and no salvage surgery was needed. CONCLUSIONS Hypo-FSRT for acoustic neuromas achieved a high local control rate with minimal facial and trigeminal nerve morbidity.
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Affiliation(s)
- Katsuyuki Sakanaka
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Sho-goin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
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Rampp S, Scheller C, Prell J, Engelhorn T, Strauss C, Rachinger J. Magnetic resonance imaging dynamics of contrast medium uptake in vestibular schwannomas. J Neurosurg 2010; 114:394-9. [PMID: 20524826 DOI: 10.3171/2010.5.jns10307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Efficacy of radiosurgery in vestibular schwannoma (VS) is usually documented by changes of tumor size and by loss of contrast enhancement in MR imaging within the central portion of the lesion. Until now, however, correlation between contrast enhancement and timing of image acquisition in nontreated VS has not been analyzed systematically. The authors undertook this study to investigate changes in contrast enhancement with respect to latency of image acquisition after contrast agent administration. METHODS The dynamics of contrast medium uptake were evaluated with T1-weighted VIBE MR imaging sequences performed immediately and 1.5, 3.5, 4.5, 9.5, and 11.5 minutes after administration of single dose of Gd in 21 patients with nontreated medium- to large-sized VSs. Signal-to-noise (SNR) and contrast-to-noise ratio (CNR) of tumors were evaluated, and volumes of central nonenhancing areas (NEAs) were determined. RESULTS The interior appearance of the tumors changed considerably over time. The NEA significantly diminished in size (p < 0.0001, Friedman test) and almost completely disappeared in all but 2 patients. Compared to images at 1.5 minutes, NEA volumes decreased to a median of 36% at 3.5 minutes and 34% at 4.5 minutes, showing smaller changes after that-9% at 9.5 minutes and 3% at 11.5 minutes. Tumor SNR and CNR increased over time. The maximum change in the median values for SNR and CNR were a 72% increase and 117% increase, respectively; both occurred at 1.5 minutes after Gd administration. CONCLUSIONS Contrast enhancement in VS MR imaging varies according to the duration of the delay between contrast agent administration and image acquisition. Postradiotherapy changes in contrast enhancement of VS can therefore not be attributed only to effective radiotherapy. So-called "loss of central contrast enhancement" may be falsely detected because of timing. A standardized protocol with defined timing of image acquisition may increase comparability of contrast uptake in VS.
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Affiliation(s)
- Stefan Rampp
- Department of Neurosurgery, University of Halle-Wittenberg, Halle, Germany
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Hsu PW, Chang CN, Lee ST, Huang YC, Chen HC, Wang CC, Hsu YH, Tseng CK, Chen YL, Wei KC. Outcomes of 75 patients over 12 years treated for acoustic neuromas with linear accelerator-based radiosurgery. J Clin Neurosci 2010; 17:556-60. [PMID: 20227884 DOI: 10.1016/j.jocn.2009.09.036] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 09/18/2009] [Accepted: 09/21/2009] [Indexed: 11/26/2022]
Abstract
The aim of this study was to investigate the efficacy of linear accelerator (LINAC)-based radiosurgery in the treatment of acoustic neuromas. In this retrospective study, we enrolled 75 patients with non-neurofibromatosis type 2 acoustic neuromas who were followed-up for more than 5years. The 75 patients were divided into 3 groups: patients with a newly diagnosed tumor; those with a residual tumor; and those with a recurrent tumor. The average follow-up period was 97.8months. The overall tumor progression-free rate was 92%, and corresponding rates among those with newly diagnosed tumors was 100%, residual tumors was 84.4%, and recurrent tumors was 92.8% (p=0.028). Lesion localization using CT scans correlated with a higher tendency for tumor progression than lesion localization using CT-MRI fusion images (15.6% versus 2.4%, respectively). Residual tumors treated with radiosurgery have a higher progression rate, and careful lesion localization using CT-MRI image fusion is required.
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Affiliation(s)
- Peng-Wei Hsu
- Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University, 5 Fu-Hsing St., Kweishan, Taoyuan 333, Taiwan
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Sughrue ME, Yang I, Han SJ, Aranda D, Kane AJ, Amoils M, Smith ZA, Parsa AT. Non-audiofacial morbidity after Gamma Knife surgery for vestibular schwannoma. Neurosurg Focus 2009; 27:E4. [PMID: 19951057 DOI: 10.3171/2009.9.focus09198] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECT While many studies have been published outlining morbidity following radiosurgical treatment of vestibular schwannomas, significant interpractitioner and institutional variability still exists. For this reason, the authors conducted a systematic review of the literature for non-audiofacial-related morbidity after the treatment of vestibular schwannoma with radiosurgery. METHODS The authors performed a comprehensive search of the English-language literature to identify studies that published outcome data of patients undergoing radiosurgery treatment for vestibular schwannomas. In total, 254 articles were found that described more than 50,000 patients and were analyzed for satisfying the authors' inclusion criteria. Patients from these studies were then separated into 2 cohorts based on the marginal dose of radiation: < or = 13 Gy and > 13 Gy. All tumors included in this study were < 25 mm in their largest diameter. RESULTS A total of 63 articles met the criteria of the established search protocol, which combined for a total of 5631 patients. Patients receiving > 13 Gy were significantly more likely to develop trigeminal nerve neuropathy than those receiving < 13 Gy (p < 0.001). While we found no relationship between radiation dose and the rate of developing hydrocephalus (0.6% for both cohorts), patients with hydrocephalus who received doses > 13 Gy appeared to have a higher rate of symptomatic hydrocephalus requiring shunt treatment (96% [> 13 Gy] vs 56% [< or = 13 Gy], p < 0.001). The rates of vertigo or balance disturbance (1.1% [> 13 Gy] vs 1.8% [< or = 13 Gy], p = 0.001) and tinnitus (0.1% [> 13 Gy] vs 0.7% [< or = 13 Gy], p = 0.001) were significantly higher in the lower dose cohort than those in the higher dose cohort. CONCLUSIONS The results of our review of the literature provide a systematic summary of the published rates of nonaudiofacial morbidity following radiosurgery for vestibular schwannoma.
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Affiliation(s)
- Michael E Sughrue
- Department of Neurological Surgery, University of California, San Francisco, California 94117, USA
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Lin YC, Wang CC, Wai YY, Wan YL, Ng SH, Chen YL, Liu HL, Wang JJ. Significant temporal evolution of diffusion anisotropy for evaluating early response to radiosurgery in patients with vestibular schwannoma: findings from functional diffusion maps. AJNR Am J Neuroradiol 2009; 31:269-74. [PMID: 19779002 DOI: 10.3174/ajnr.a1799] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Outcome evaluation in clinical oncology is conventionally based on long-term volumetric changes in the tumor size. The purpose of this study was to prospectively investigate the usefulness of fDMs in incorporating anisotropic diffusion in the evaluation of early response after radiosurgery in patients with vestibular schwannoma. MATERIALS AND METHODS The MD, FA, and IVDC were calculated by using simple averaging methods and fDMs. Six patients with vestibular schwannoma treated with stereotactic radiosurgery underwent longitudinal DTI studies on a 3T MR imaging scanner (maximum follow-up, 6 months). Posttreatment DTI data were spatially coregistered with pretreatment scans. RESULTS Tumors did not change significantly in size until 6 months after treatment. Diffusion indices changed significantly during the study period. There was a transient decrease in averaged MD followed by a significant increase. IVDC showed an opposite behavior compared with MD. FA decreased continuously throughout the study period. Functional diffusion maps showed a heterogeneous response of tumors to treatment, thereby providing complementary information to simple averaged values. CONCLUSIONS DTI allows early detection of therapeutic-induced changes in patients with vestibular schwannoma. Functional diffusion maps incorporating anisotropic diffusion may aid in assessing the heterogeneity of the therapeutic response in this patient group.
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Affiliation(s)
- Y-C Lin
- Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Department of Electrical Engineering, Chang Gung University, Taiwan, Republic of China
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Hayashi K, Ushijima R, Matsuo T, Kitagawa N, Suyama K, Nagata I. The 150th anniversary of Nagasaki University School of Medicine: recovery from the atomic disaster and evolution of the department of neurosurgery. Neurosurgery 2009; 65:595-9; discussion 599-600. [PMID: 19687706 DOI: 10.1227/01.neu.0000350872.53258.e7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
NAGASAKI IS LOCATED on the western edge of Japan, closer to the Asian continent. Because of this geographical proximity, Nagasaki became a gateway for the introduction of continental culture and civilization to Japan. After the port of Nagasaki was opened for trade with the Portuguese in 1571, Nagasaki had a central role in cultural exchange with the West and China until the latter half of the 19th century. As a result of the political situation, students came to Nagasaki from all over Japan to obtain information on Western science, especially in medicine, turning Nagasaki into a hub for modern academic studies. The first medical facility in Japan educating doctors in the Western style was founded in Nagasaki in 1857. Despite the tragedy of World War II, the medical school arose again. More than 10 000 physicians have completed their studies at the medical school since its founding. The Department of Neurosurgery at Nagasaki University had its origins within the Second Department of Surgery and became an independent department in 1973. The post of professor was assumed by Kazuo Mori and succeeded in 1991 by Shobu Shibata and in 2003 by Izumi Nagata, who holds the post at the time of this writing. Neurosurgery is dynamic and constantly changing at Nagasaki University with work in progress on technological, diagnostic, and surgical innovations that permit the treatment of highly complex cases. In 2007, the 150th anniversary of the founding of Nagasaki University School of Medicine was celebrated with a number of commemorative events.
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Affiliation(s)
- Kentaro Hayashi
- Department of Neurosurgery, Nagasaki University School of Medicine, Nagasaki, Japan.
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Wai Y, Chu J, Wang C, Lin Y, Lin G, Wan Y, Wang J. An integrated diffusion map for the analysis of diffusion properties: a feasibility study in patients with acoustic neuroma. Acad Radiol 2009; 16:428-34. [PMID: 19268854 DOI: 10.1016/j.acra.2008.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 10/23/2008] [Accepted: 10/28/2008] [Indexed: 10/21/2022]
Abstract
RATIONALE AND OBJECTIVES To develop an integrated diffusion map (iDM) for evaluation of diffusion properties, including the mean diffusivity and diffusion anisotropy concurrently. MATERIALS AND METHODS The proposed integrated diffusion map consisted of trace and the deviation tensor. It measures the diffusion distributions from a region of interest. Diffusion tensor imaging was acquired from nine healthy volunteers and four patients with acoustic neuroma before and 3 months after the stereotactic radiosurgery. Five regions of interest were selected from healthy subjects and the whole tumor from the patients. The diffusion properties were analyzed in the proposed integrated diffusion map. RESULTS In healthy subjects, iDM showed different distributions in regions of interest that can lead to cluster segmentation. In monitoring the treatment response, the number of pixels with meaningful changes in iDM is 12.5% compared to 32.37% in apparent diffusion coefficient and 16.67% in fractional anisotropy. It suggested the effect from radiation therapy might affect the anisotropic diffusion. The interpretation of the diffusion properties, such as changes in mean diffusivity and anisotropy, should be treated in an integrated method. CONCLUSIONS The integrated diffusion map can be used to analyze the diffusion properties in a comprehensive manner.
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Abram S, Rosenblatt P, Holcomb S. Stereotactic radiation techniques in the treatment of acoustic schwannomas. 2007. Neurosurg Clin N Am 2008; 19:367-77, vii-viii. [PMID: 18534345 DOI: 10.1016/j.nec.2008.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Medical decision-making is based on benefit-to-cost analysis. Optimally, treatment obtains a high degree of benefit while minimizing the physical, social, and financial costs. The goals of the treatment of acoustic schwannomas are prohibiting tumor growth and alleviation of symptoms caused by damage to local structures. These symptoms-tinnitus, ataxia, and hearing loss-secondary to eighth nerve dysfunction, as well as symptoms arising from damage to adjacent structures such as the facial nerve, trigeminal nerve, or pons, can be caused by tumor growth or treatment. Determination of optimal therapy must also take into account an understanding of the natural history of the disease, because acoustic schwannomas are slow-growing benign tumors that when left untreated, usually enlarge over time and cause problems.
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Affiliation(s)
- Steven Abram
- Neuroscience Institute of Saint Thomas Hospital, Nashville, TN, USA.
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Nomiya T, Tsuji H, Hirasawa N, Kato H, Kamada T, Mizoe J, Kishi H, Kamura K, Wada H, Nemoto K, Tsujii H. Carbon ion radiation therapy for primary renal cell carcinoma: initial clinical experience. Int J Radiat Oncol Biol Phys 2008; 72:828-33. [PMID: 18374507 DOI: 10.1016/j.ijrobp.2008.01.043] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2007] [Revised: 01/03/2008] [Accepted: 01/04/2008] [Indexed: 12/01/2022]
Abstract
PURPOSE Renal cell carcinoma (RCC) is known as a radioresistant tumor, and there are few reports on radiotherapy for primary RCC. We evaluated the efficacy of carbon ion radiotherapy (CIRT) for patients with RCC. METHODS AND MATERIALS Data for patients with RCC who received CIRT were analyzed. A median total dose of 72 GyE (gray equivalents) in 16 fractions was administered without any additional treatment. Clinical stage was determined based on TNM classification by the International Union Against Cancer (UICC). Local recurrence was defined as definite tumor regrowth after treatment. RESULTS Data for 10 patients were included in the analyses, including 7 patients with Stage I and 3 patients with Stage IV (T4NxM0 or TxN2M0) disease. The median maximum diameter of the tumor was 43 mm (24-120 mm). The median follow-up for surviving patients was 57.5 months (9-111 months). The 5-year local control rate, progression-free survival rate, cause-specific survival rate, and overall survival rates were 100%, 100%, 100%, and 74%, respectively. Interestingly, treated tumors showed very slow shrinkage, and the tumor in 1 case has been shrinking for 9 years. One patient with muscular invasion (T4 tumor) developed Grade 4 skin toxicity, but no other toxicity greater than Grade 2 was observed. CONCLUSIONS This is one of the few reports on curative radiotherapy for primary RCC. The response of the tumor to treatment was uncommon. However despite inclusion of T4 and massive tumors, favorable local controllability has been shown. The results indicate the possibility of radical CIRT, as well as surgery, for RCC.
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Affiliation(s)
- Takuma Nomiya
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), Chiba, Japan
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Likhterov I, Allbright RM, Selesnick SH. LINAC Radiosurgery and Radiotherapy Treatment of Acoustic Neuromas. Neurosurg Clin N Am 2008; 19:345-65, vii. [DOI: 10.1016/j.nec.2008.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Meijer OWM, Weijmans EJ, Knol DL, Slotman BJ, Barkhof F, Vandertop WP, Castelijns JA. Tumor-volume changes after radiosurgery for vestibular schwannoma: implications for follow-up MR imaging protocol. AJNR Am J Neuroradiol 2008; 29:906-10. [PMID: 18296549 DOI: 10.3174/ajnr.a0969] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The outcome of radiosurgery for vestibular schwannoma (VS) is assessed by posttreatment measurement of tumor size and could be influenced by the timing and quality of the assessment. This study evaluates the volumetric changes of VS after radiosurgery and proposes a radiologic follow-up program. MATERIALS AND METHODS Of 142 patients with VS treated with radiosurgery, we selected patients who were followed at least 3 times during a minimum of 32 months with a T1-weighted gadolinium-enhanced high-resolution 3D MR imaging examination identical to the pretreatment MR imaging. Forty-five patients were identified with a mean follow-up of 50 months (range, 32-78 months). Pre- and posttreatment tumor volumes were calculated by using BrainSCAN software by manually contouring tumors on each MR imaging study. Volume changes of >13% were defined as events. RESULTS At last follow-up MR imaging, volumes were smaller in 37 (82.2%) of the 45 patients. Eleven (29.7%) of these 37 tumors showed transient swelling preceding regression, with a median time to regression of 34 months (range, 20-55 months). Seven (15.6%) of the 45 tumors had volume progression compared with the tumor on pretreatment MR imaging studies. Of these 7 tumors, 3, however, had volume regression compared with the preceding MR imaging study, and in 4, volume progression was ongoing. One tumor remained the same. CONCLUSIONS Tumor-volume measurements by standardized T1-weighted gadolinium-enhanced high-resolution 3D MR imaging follow-up protocols revealed good local control of VS after radiosurgery. The first-follow-up MR imaging at 2 years and the second at 5 years postradiosurgery differentiated transient progression from ongoing progression and may prevent unnecessary therapeutic interventions.
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Affiliation(s)
- O W M Meijer
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, the Netherlands.
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Kim KM, Park CK, Chung HT, Paek SH, Jung HW, Kim DG. Long-term Outcomes of Gamma Knife Stereotactic Radiosurgery of Vestibular Schwannomas. J Korean Neurosurg Soc 2007; 42:286-92. [PMID: 19096558 DOI: 10.3340/jkns.2007.42.4.286] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2007] [Accepted: 08/22/2007] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Gamma Knife Stereotactic Radiosurgery (GK SRS) has become an important treatment modality for vestibular schwannomas. We evaluated the tumor control rate, patterns of tumor volume change and preservation of hearing following low-dose radiation for vestibular schwannomas in a homogeneous cohort group in which the mean marginal dose was 12 Gy. METHODS A total of 59 patients were enrolled in this study. All enrolled patients were followed-up for at least 5 years and the radiation dose was 11-13 Gy. Regular MRI, audiometry and clinical evaluations were done and tumor volumes were obtained from MRI using the OSIRIS program. RESULTS The tumor control rate was 97%. We were able to classify the patterns of change in tumor volume into three categories. Transient increases in tumor volume were detected in 29% of the patients and the maximum transient increase in tumor volume was identified at 6 to 30 months after GK SRS. The transient increases in tumor volume ranged from 121% to 188%. Hearing was preserved in 4 of the 12 patients who had serviceable hearing prior to treatment. There were no other complications associated with GK SRS. CONCLUSION Low-dose GK SRS was an effective and safe mode of treatment for vestibular schwannomas in comparison to the previously used high-dose GK SRS. Transient increases in tumor volume can be identified during the follow-up period after low-dose GK SRS for vestibular schwannomas. Physicians should be aware that these increases are not always indicative of treatment failure and that close observation is required following treatments. Unfortunately, a satisfactory hearing preservation rate was not achieved by reducing the radiation dose. It is thought that hearing preservation is a more sophisticated problem and further research is required.
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Affiliation(s)
- Kang-Min Kim
- Department of Neurosurgery, Seoul National University, College of Medicine, Seoul, Korea
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