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Hwang I, Choi SH, Kim JW, Yeon EK, Lee JY, Yoo RE, Kang KM, Yun TJ, Kim JH, Sohn CH. Response prediction of vestibular schwannoma after gamma-knife radiosurgery using pretreatment dynamic contrast-enhanced MRI: a prospective study. Eur Radiol 2022; 32:3734-3743. [PMID: 35084518 DOI: 10.1007/s00330-021-08517-1] [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: 06/07/2021] [Revised: 11/09/2021] [Accepted: 12/10/2021] [Indexed: 11/04/2022]
Abstract
OBJECTIVES There are few known predictive factors for response to gamma-knife radiosurgery (GKRS) in vestibular schwannoma (VS). We investigated the predictive role of pretreatment dynamic contrast-enhanced (DCE)-MRI parameters regarding the tumor response after GKRS in sporadic VS. METHODS This single-center prospective study enrolled participants between April 2017 and February 2019. We performed a volumetric measurement of DCE-MRI-derived parameters before GKRS. The tumor volume was measured in a follow-up MRI. The pharmacokinetic parameters were compared between responders and nonresponders according to 20% or more tumor volume reduction. Stepwise multivariable logistic regression analyses were performed, and the diagnostic performance of DCE-MRI parameters for the prediction of tumor response was evaluated by receiver operating characteristic curve analysis. RESULTS Ultimately, 35 participants (21 women, 52 ± 12 years) were included. There were 22 (62.9%) responders with a mean follow-up interval of 30.2 ± 5.7 months. Ktrans (0.036 min-1 vs. 0.057 min-1, p = .008) and initial area under the time-concentration curve within 90 s (IAUC90) (84.4 vs. 143.6, p = .003) showed significant differences between responders and nonresponders. Ktrans (OR = 0.96, p = .021) and IAUC90 (OR = 0.97, p = .004) were significant differentiating variables in each multivariable model with clinical variables for tumor response prediction. Ktrans showed a sensitivity of 81.8% and a specificity of 69.2%, and IAUC90 showed a sensitivity of 100% and a specificity of 53.8% for tumor response prediction. CONCLUSION DCE-MRI (particularly Ktrans and IAUC90) has the potential to be a predictive factor for tumor response in VS after GKRS. KEY POINTS •Pretreatment prediction of gamma-knife radiosurgery response in vestibular schwannoma is still challenging. •Dynamic contrast-enhanced MRI could have predictive value for the response of vestibular schwannoma after gamma-knife radiosurgery.
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Affiliation(s)
- Inpyeong Hwang
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Seung Hong Choi
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea. .,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea. .,Institute of Radiation Medicine, Seoul National University Medical Research Center, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea. .,Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, 08826, Republic of Korea.
| | - Jin Wook Kim
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Eung Koo Yeon
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Ji Ye Lee
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Roh-Eul Yoo
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Institute of Radiation Medicine, Seoul National University Medical Research Center, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - Koung Mi Kang
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Tae Jin Yun
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ji-Hoon Kim
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chul-Ho Sohn
- Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Institute of Radiation Medicine, Seoul National University Medical Research Center, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
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2
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Berger A, Galbraith K, Snuderl M, Golfinos JG, Kondziolka D. Absence of residual tumor tissue after Gamma Knife radiosurgery followed by resection of a vestibular schwannoma: illustrative case. JOURNAL OF NEUROSURGERY. CASE LESSONS 2022; 3:CASE21614. [PMID: 36130577 PMCID: PMC9379734 DOI: 10.3171/case21614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 11/01/2021] [Indexed: 04/30/2023]
Abstract
BACKGROUND Late pathology after vestibular schwannoma radiosurgery is uncommon. The authors presented a case of a resected hemorrhagic mass 13 years after radiosurgery, when no residual tumor was found. OBSERVATIONS A 56-year-old man with multiple comorbidities, including myelodysplastic syndrome cirrhosis, received Gamma Knife surgery for a left vestibular schwannoma. After 11 years of stable imaging assessments, the lesion showed gradual growth until a syncopal event occurred 2 years later, accompanied by progressive facial weakness and evidence of intralesional hemorrhage, which led to resection. However, histopathological analysis of the resected specimen showed hemorrhage and reactive tissue but no definitive residual tumor. LESSONS This case demonstrated histopathological evidence for the role of radiosurgery in complete elimination of tumor tissue. Radiosurgery for vestibular schwannoma carries a rare risk for intralesional hemorrhage in select patients.
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Affiliation(s)
| | - Kristyn Galbraith
- Pathology, NYU Langone Medical Center, New York University, New York, New York
| | - Matija Snuderl
- Pathology, NYU Langone Medical Center, New York University, New York, New York
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Saglam Y, Samanci Y, Bolukbasi Y, Peker S. Dosimetric comparison of volumetric modulated arc therapy with TrueBeam LINAC and hypofractionated radiosurgery with gamma knife ICON for large (>10 cm3) skull base meningiomas. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2022; 30:1201-1211. [PMID: 36189527 DOI: 10.3233/xst-221264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
BACKGROUND Multi Fractionated stereotactic radiosurgery (MF-SRS) of Linac has an essential role in the treatment of skull base meningiomas (sbMNG). However, Gamma Knife Icon (GK) allows MF-SRS using mask immobilization with onboard image guidance. OBJECTIVE This dosimetric study aims to investigate whether equivalent plan quality can be achieved with Volumetric Modulated Arc Therapy (VMAT) in patients with large sbMNG (>10 cm3) previously treated with GK. METHODS Twenty patients with the median target volume of 19.7cm3 are re-planned by using VMAT with 20 Gy in 5 fractions. Plan qualities are compared to tumor coverage, paddick conformity index (PCI), gradient index (GI), V4 Gy, V10 Gy, V12 Gy, optic chiasm V20 Gy, brainstem V23 Gy, optic nerve V25 Gy volumes, and maximum doses for all. Additionally, beam-on time and approximate planning time are also analyzed and compared. RESULTS All plans provide adequate clinical requirements. First, the CI is comparable for the GK and VMAT (0.99±0.01 vs. 1.13±0.20; p = 0.18). Second, VMAT has a significantly higher GI than GK (3.81±0.35 vs. 2.63±0.09; p < 0.001). Third, the PCI is significantly higher in GK than VMAT (0.76±0.05 vs. 0.70±0.07; p < 0.001). The lower GI of the GK also results in significantly lower V4 Gy (156.1±43.8 vs. 207.5±40.1 cm3, p < 0.001) and V10 Gy (26.1±9.0 vs. 28.9±7.7 cm3, p < 0.001) compared to VMAT. Last, the VMAT reduces beam-on time (4.8±0.5 vs. 19±1.1 min.; p < 0.001). CONCLUSION Although both systems have succeeded in creating effective plans in clinical practice, the GK reveals more effective lower normal brain tissue doses. However, the shorter treatment time with LINAC, excluding the total procedure time, can be considered advantageous over GK.
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Affiliation(s)
- Yucel Saglam
- Department of Radiation Oncology, Koc University, School of Medicine, Davutpasa Caddesi, Topkapi, Istanbul, Turkey
| | - Yavuz Samanci
- Department of Neurosurgery, Koc University, School of Medicine, Davutpasa Caddesi, Topkapi, Istanbul, Turkey
| | - Yasemin Bolukbasi
- Department of Radiation Oncology, Koc University, School of Medicine, Davutpasa Caddesi, Topkapi, Istanbul, Turkey
| | - Selcuk Peker
- Department of Neurosurgery, Koc University, School of Medicine, Davutpasa Caddesi, Topkapi, Istanbul, Turkey
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Dougherty MC, Shibata SB, Hansen MR. The biological underpinnings of radiation therapy for vestibular schwannomas: Review of the literature. Laryngoscope Investig Otolaryngol 2021; 6:458-468. [PMID: 34195368 PMCID: PMC8223465 DOI: 10.1002/lio2.553] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/05/2021] [Accepted: 03/12/2021] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE Radiation therapy is a mainstay in the treatment of numerous neoplasms. Numerous publications have reported good clinical outcomes for primary radiation therapy for Vestibular Schwannomas (VS). However, there are relatively few pathologic specimens of VSs available to evaluate post-radiation, which has led to a relative dearth in research on the cellular mechanisms underlying the effects of radiation therapy on VSs. METHODS Here we review the latest literature on the complex biological effects of radiation therapy on these benign tumors-including resistance to oxidative stress, mechanisms of DNA damage repair, alterations in normal growth factor pathways, changes in surrounding vasculature, and alterations in immune responses following radiation. RESULTS Although VSs are highly radioresistant, radiotherapy is often successful in arresting their growth. CONCLUSION By better understanding the mechanisms underlying these effects, we could potentially harness such mechanisms in the future to potentiate the clinical effects of radiotherapy on VSs. LEVEL OF EVIDENCE N/A.
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Affiliation(s)
- Mark C. Dougherty
- Department of NeurosurgeryUniversity of Iowa Hospitals & ClinicsIowa CityIowaUSA
| | - Seiji B. Shibata
- Department of Otolaryngology, Keck School of Medicine of USCUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Marlan R. Hansen
- Department of Otolaryngology—Head & Neck SurgeryUniversity of Iowa Hospitals & ClinicsIowa CityIowaUSA
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Park HR, Lee JM, Park KW, Kim JH, Jeong SS, Kim JW, Chung HT, Kim DG, Paek SH. Fractionated Gamma Knife Radiosurgery as Initial Treatment for Large Skull Base Meningioma. Exp Neurobiol 2018; 27:245-255. [PMID: 30022876 PMCID: PMC6050410 DOI: 10.5607/en.2018.27.3.245] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/02/2018] [Accepted: 05/24/2018] [Indexed: 11/19/2022] Open
Abstract
We present our experience on the hypofractionated Gamma Knife radiosurgery (FGKS) for large skull base meningioma as an initial treatment. We retrospectively reviewed 23 patients with large skull base meningioma ≥10 cm3 who underwent FGKS as the initial treatment option. The mean volume of tumors prior to radiosurgery was 21.2±15.63 cm3 (range, 10.09~71.42). The median total margin dose and marginal dose per fraction were 18 Gy (range, 15~20) and 6 Gy (range, 5~6), respectively. Patients underwent three or four fractionations in consecutive days with the same Leksell® frame. The mean follow-up duration was 38 months (range, 17~78). There was no mortality. At the last follow-up, the tumor volume was stationary in 15 patients (65.2%) and had decreased in 8 patients (34.8%). Six patients who had cranial neuropathy at the time of FGKS showed improvement at the last clinical follow-up. Following FGKS, 4 patients (17%) had new cranial neuropathy. The trigeminal neuropathy was the most common and all were transient. The mean Karnofsky Performance Status score at pre-FGKS and the last clinical follow-up was 97.0±10.4 points (median, 100) and 98.6±6.9 (median, 100) points, respectively. FGKS has showed satisfactory tumor control with functional preservation for large skull base meningiomas. Further prospective studies of large cohorts with long term follow-up are required to clarify the efficacy in the tumor control and functional outcome as well as radiation toxicity.
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Affiliation(s)
- Hye Ran Park
- Department of Neurosurgery, Soonchunhyang University Seoul Hospital, Seoul 04401, Korea
| | - Jae Meen Lee
- Department of Neurosurgery, Pusan National University Hospital, Busan 49241, Korea
| | - Kwang-Woo Park
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Jung Hoon Kim
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Sang Soon Jeong
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Jin Wook Kim
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Hyun-Tai Chung
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Dong Gyu Kim
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea
| | - Sun Ha Paek
- Department of Neurosurgery, Seoul National University Hospital, Seoul 03080, Korea.,Cancer Research Institute, Seoul National University, Seoul 03080, Korea.,Ischemia Hypoxia Disease Institute, Seoul National University, Seoul 03080, Korea
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6
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Marston AP, Jacob JT, Carlson ML, Pollock BE, Driscoll CLW, Link MJ. Pretreatment growth rate as a predictor of tumor control following Gamma Knife radiosurgery for sporadic vestibular schwannoma. J Neurosurg 2017; 127:380-387. [DOI: 10.3171/2016.5.jns153013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVEOver the last 30 years, stereotactic radiosurgery (SRS) has become an established noninvasive treatment alternative for small- to medium-sized vestibular schwannoma (VS). This study aims to further define long-term SRS tumor control in patients with documented pretreatment tumor growth for whom conservative observation failed.METHODSA prospective clinical database was queried, and patients with sporadic VS who elected initial observation and subsequently underwent SRS after documented tumor growth between 2004 and 2014 were identified. Posttreatment tumor growth or shrinkage was determined by a ≥ 2-mm increase or decrease in maximum linear dimension, respectively.RESULTSSixty-eight patients met study inclusion criteria. The median pre- and posttreatment observation periods were 16 and 43.5 months, respectively. The median dose to the tumor margin was 13 Gy (range 12–14 Gy), and the median maximum dose was 26 Gy (range 24–28 Gy). At the time of treatment, 59 tumors exhibited extracanalicular (EC) extension, and 9 were intracanalicular (IC). Of the 59 EC VSs, 50 (85%) remained stable or decreased in size following treatment, and 9 (15%) enlarged by > 2 mm. Among EC tumors, the median pretreatment tumor growth rate was 2.08 mm/year for tumors that decreased or were stable, compared with 3.26 mm/year for tumors that grew following SRS (p = 0.009). Patients who demonstrated a pretreatment growth rate of < 2.5 mm/year exhibited a 97% tumor control rate, compared with 69% for those demonstrating ≥ 2.5 mm/year of growth prior to SRS (p = 0.007). No other analyzed variables were found to predict tumor growth following SRS.CONCLUSIONSOverall, SRS administered using a marginal dose between 12–14 Gy is highly effective in treating VSs in which initial observation fails. Tumor control is achieved in 97% of VSs that exhibit slow (< 2.5 mm/year) pretreatment growth; however, SRS is less successful in treating tumors exhibiting rapid growth (≥ 2.5 mm/year).
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Affiliation(s)
| | | | | | - Bruce E. Pollock
- 2Neurologic Surgery, and
- 3Radiation Oncology, Mayo Clinic School of Medicine, Rochester, Minnesota
| | | | - Michael J. Link
- Departments of 1Otolaryngology-Head and Neck Surgery,
- 2Neurologic Surgery, and
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Bonne NX, Vitte J, Chareyre F, Karapetyan G, Khankaldyyan V, Tanaka K, Moats RA, Giovannini M. An allograft mouse model for the study of hearing loss secondary to vestibular schwannoma growth. J Neurooncol 2016; 129:47-56. [PMID: 27177628 DOI: 10.1007/s11060-016-2150-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 05/06/2016] [Indexed: 02/07/2023]
Abstract
Vestibular schwannoma is a benign neoplasm arising from the Schwann cell sheath of the auditory-vestibular nerve. It most commonly affects both sides in the genetic condition Neurofibromatosis type 2, causing progressive high frequency sensorineural hearing loss. Here, we describe a microsurgical technique and stereotactic coordinates for schwannoma cell grafting in the vestibular nerve region that recapitulates local tumor growth in the cerebellopontine angle and inner auditory canal with resulting hearing loss. Tumor growth was monitored by bioluminescence and MRI in vivo imaging, and hearing assessed by auditory brainstem responses. These techniques, by potentially enabling orthotopic grafting of a variety of cell lines will allow studies on the pathogenesis of tumor-related hearing loss and preclinical drug evaluation, including hearing endpoints, for NF2-related and sporadic schwannomas.
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Affiliation(s)
- Nicolas-Xavier Bonne
- House Research Institute, Center for Neural Tumor Research, Los Angeles, CA, USA.,Department of Otology and Neurotology, University Hospital of Lille, and INSERM U1008 "Controlled Drug Delivery System and Biomaterials", University of Lille, Lille, France
| | - Jérémie Vitte
- Department of Head and Neck Surgery, University of California Los Angeles, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Jonsson Comprehensive Cancer Center, University of California Los Angeles, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Fabrice Chareyre
- House Research Institute, Center for Neural Tumor Research, Los Angeles, CA, USA
| | - Gevorg Karapetyan
- Department of Radiology, USC Keck School of Medicine, The Saban Research Institute of Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Vazgen Khankaldyyan
- Department of Radiology, USC Keck School of Medicine, The Saban Research Institute of Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Karo Tanaka
- House Research Institute, Center for Neural Tumor Research, Los Angeles, CA, USA
| | - Rex A Moats
- Department of Radiology, USC Keck School of Medicine, The Saban Research Institute of Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Marco Giovannini
- Department of Head and Neck Surgery, University of California Los Angeles, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA. .,Jonsson Comprehensive Cancer Center, University of California Los Angeles, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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8
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Jacob A, Igarashi S, Platto T, Khan R, Jain R. The Solid Component of Radiographically Non-Growing, Post-Radiated Vestibular Schwannoma Retains Proliferative Capacity: Implications for Patient Counseling. Ann Otol Rhinol Laryngol 2015; 124:834-40. [PMID: 26019282 DOI: 10.1177/0003489415588128] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Nearly all radiated vestibular schwannomas (VS) have solid tissue remaining at the radiation bed. The viability and proliferation capacity of this tissue has never been objectively assessed. The goals of our study were to (1) determine whether this tissue retains the morphological and immunohistochemical features of VS and (2) evaluate whether the tissue is capable of proliferation in cell culture. METHODS Case history, magnetic resonance imaging (MRI), cell culture, histology, and immunohistochemistry. RESULTS We report the first case of a post-radiated, sporadic VS patient whose non-growing, residual MR-enhancing solid tissue was examined histologically and in cell culture. These cells were architecturally identical to non-radiated VS, had a Ki67 proliferative index similar to non-radiated sporadic and NF2-associated VS, were S100 positive, and grew in culture with kinetics comparable to non-radiated VS. CONCLUSION The long-term risk for delayed tumor growth and/or secondary malignancy in radiated VS patients is unknown. Because the average life span in the United States is nearly 80 years, patients should be informed that (1) residual VS cells are viable even when tumors appear to be non-growing on MRI, (2) post-radiation surveillance imaging is required indefinitely, and (3) radiation may incur more risk in those patients with life expectancy>20-25 years.
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Affiliation(s)
- Abraham Jacob
- University of Arizona Ear Institute, University of Arizona Department of Otolaryngology, University of Arizona Cancer Center, The University of Arizona Bio5 Institute, Tucson, Arizona, USA
| | - Suzu Igarashi
- University of Arizona Ear Institute, University of Arizona Department of Otolaryngology, University of Arizona Cancer Center, Tucson, Arizona, USA
| | - Terry Platto
- University of Arizona Ear Institute and University of Arizona College of Medicine, Tucson, Arizona, USA
| | - Rihan Khan
- University of Arizona Department of Medical Imaging, Tucson, Arizona, USA
| | - Richa Jain
- University of Arizona Department of Pathology, Tucson, Arizona, USA
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9
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Kondziolka D, Shin SM, Brunswick A, Kim I, Silverman JS. The biology of radiosurgery and its clinical applications for brain tumors. Neuro Oncol 2014; 17:29-44. [PMID: 25267803 DOI: 10.1093/neuonc/nou284] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Stereotactic radiosurgery (SRS) was developed decades ago but only began to impact brain tumor care when it was coupled with high-resolution brain imaging techniques such as computed tomography and magnetic resonance imaging. The technique has played a key role in the management of virtually all forms of brain tumor. We reviewed the radiobiological principles of SRS on tissue and how they pertain to different brain tumor disorders. We reviewed the clinical outcomes on the most common indications. This review found that outcomes are well documented for safety and efficacy and show increasing long-term outcomes for benign tumors. Brain metastases SRS is common, and its clinical utility remains in evolution. The role of SRS in brain tumor care is established. Together with surgical resection, conventional radiotherapy, and medical therapies, patients have an expanding list of options for their care. Clinicians should be familiar with radiosurgical principles and expected outcomes that may pertain to different brain tumor scenarios.
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Affiliation(s)
- Douglas Kondziolka
- Department of Neurosurgery, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.); Department of Radiation Oncology, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.)
| | - Samuel M Shin
- Department of Neurosurgery, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.); Department of Radiation Oncology, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.)
| | - Andrew Brunswick
- Department of Neurosurgery, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.); Department of Radiation Oncology, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.)
| | - Irene Kim
- Department of Neurosurgery, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.); Department of Radiation Oncology, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.)
| | - Joshua S Silverman
- Department of Neurosurgery, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.); Department of Radiation Oncology, NYU Langone Medical Center, New York University, New York, New York (D.K., S.M.S., A.B., I.K., J.S.S.)
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10
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Abstract
Radiosurgery is commonly considered to be effective through a destructive physical mechanism acting on neural tissue. However, the results of modern neurophysiological, radiological, and histological studies are providing a basis on which to question this assumption. There are now multiple pieces of evidence pointing to a nonlesional mechanism of the radiosurgical action. It appears that tissue destruction is absent or minimal and in almost all cases insufficient to explain the clinical effects produced. There is a real possibility that radiosurgery induces changes in the functioning of neural tissue by differential effects on various neuronal populations and remodeling the glial environment, leading to modulation of function while preserving basic processing. Hence, the majority of radiosurgical procedures induce the desired biological effect without histological destruction of tissue. These findings may result in a major paradigm shift in the treatment of functional brain disorders.
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Affiliation(s)
- Jean Régis
- Department of Stereotactic and Functional Neurosurgery, Aix Marseille University, Timone University Hospital, and INSERM U751, 264 rue Saint Pierre, Marseille, 13385, Cedex 05, France.
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12
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Lee CC, Pan DHC, Wu JC, Chung WY, Wu HM, Yang HC, Liu KD, Guo WY, Shih YH. Gamma Knife Radiosurgery for Glomus Jugulare and Tympanicum. Stereotact Funct Neurosurg 2011; 89:291-8. [DOI: 10.1159/000328890] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Accepted: 04/26/2011] [Indexed: 12/25/2022]
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13
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Is radiosurgery a neuromodulation therapy? J Neurooncol 2010; 98:155-62. [DOI: 10.1007/s11060-010-0226-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Accepted: 05/06/2010] [Indexed: 11/25/2022]
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14
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15
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Lobato-Polo J, Kondziolka D, Zorro O, Kano H, Flickinger JC, Lunsford LD. GAMMA KNIFE RADIOSURGERY IN YOUNGER PATIENTS WITH VESTIBULAR SCHWANNOMAS. Neurosurgery 2009; 65:294-300; discussion 300-1. [DOI: 10.1227/01.neu.0000345944.14065.35] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Abstract
OBJECTIVE
Management options for patients with vestibular schwannoma include observation, surgical resection, stereotactic radiosurgery (SRS), and stereotactic radiation therapy. In younger patients, resection is often advocated because of concern regarding the long-term effects of radiation. We studied tumor response and clinical outcomes after SRS in such patients.
METHODS
We reviewed long-term outcomes in 55 patients with vestibular schwannomas. Patients were 40 years of age or younger, underwent gamma knife (GK) SRS between 1987 and 2003, and were followed up for a minimum of 4 years. The median patient age was 35 years (range, 13–40 years). Forty-one patients had Gardner-Robertson class 1 to 4 hearing. Thirteen patients (24%) had undergone surgical removal. The median tumor volume was 1.7 mm3. The median tumor margin dose was 13.0 Gy (range, 11–20 Gy).
RESULTS
At a median of 5.3 years, (range, 4–20 years), 2 of 55 patients underwent GK SRS for a second time; 1 of these patients had had a recurrence after initial resection. The 5-year rate of freedom from additional management was 96%. Hearing preservation rates (i.e., remaining within the same Gardner-Robertson hearing class) were 93%, 87%, and 87% at 3, 5, and 10 years, respectively. In patients with serviceable hearing before SRS, it was maintained in 100%, 93%, and 93% of patients at 3, 5, and 10 years, respectively. Hearing preservation was related to a margin dose lower than 13 Gy (P = 0.017). At the last assessment, facial and trigeminal nerve function was preserved in 98.2% and 96.4% of patients, respectively; the only facial deficit (House-Brackmann grade III) occurred in a patient who received a tumor dose of 20 Gy early in our experience (1988). None of the patients treated with doses lower than 13 Gy experienced facial or trigeminal neuropathy. All patients continued their previous level of activity or employment after GK SRS. No patient developed a secondary radiation-related tumor.
CONCLUSION
Our experience indicates that GK SRS is an effective management strategy for younger patients with vestibular schwannoma, most of whom have no additional cranial nerve dysfunction.
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Affiliation(s)
- Javier Lobato-Polo
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Douglas Kondziolka
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Oscar Zorro
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Hideyuki Kano
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - John C. Flickinger
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - L. Dade Lunsford
- Department of Neurological Surgery and the Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
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Charabi S. Acoustic Neuroma/Vestibular SchwannomaIn VivoandIn VitroGrowth Models: A Clinical and Experimental Study. Acta Otolaryngol 2009. [DOI: 10.3109/00016489709126129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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17
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Effects of ErbB2 Signaling on the Response of Vestibular Schwannoma Cells to ??-Irradiation. Laryngoscope 2008; 118:1023-30. [DOI: 10.1097/mlg.0b013e318163f920] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Vachhani JA, Friedman WA. Radiosurgery in patients with bilateral vestibular schwannomas. Stereotact Funct Neurosurg 2007; 85:273-8. [PMID: 17709979 DOI: 10.1159/000107359] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Patients with bilateral vestibular schwannomas offer a unique opportunity to determine the effectiveness of radiosurgery. By using the untreated tumor as an internal control, one can determine whether radiosurgery was able to interrupt the natural history of the treated tumor. METHODS From September 1998 to November 2004, 13 patients with neurofibromatosis type 2 had 14 tumors treated with radiosurgery at the University of Florida. A retrospective analysis was performed on these patients. Actuarial statistics were used to analyze local control in both the treated and untreated tumor. RESULTS The average follow-up length was 38 months. One patient failed to send a follow-up MRI. Actuarial local control in the treated tumors was 100% at 1 year and 92% at 2 and 5 years. Only 1 of the treated tumors continued to grow. In the untreated tumors, actuarial local control was 100% at 1 year, 78% at 2 years and 21% at 5 years. None of the untreated tumors decreased in size. CONCLUSION In all but 1 patient with follow-up data, radiosurgery successfully prevented or reversed tumor growth. Additionally, half of the untreated tumors continued to grow. This study shows that radiosurgery alters the natural history of vestibular schwannomas.
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Affiliation(s)
- Jay A Vachhani
- Department of Neurosurgery, University of Florida, Gainesville, FL 32610, USA
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Wackym PA, Runge-Samuelson CL, Poetker DM, Michel MA, Alkaf FM, Burg LS, Firszt JB. Gamma Knife Radiosurgery for Acoustic Neuromas Performed by a Neurotologist: Early Experiences and Outcomes. Otol Neurotol 2004; 25:752-61. [PMID: 15354007 DOI: 10.1097/00129492-200409000-00018] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess early outcomes after Gamma knife radiosurgery of acoustic neuromas and other skull base tumors. BACKGROUND Gamma knife radiosurgery is one of the available methods to treat acoustic neuromas, in addition to micro-surgical resection. Neuro-otologists have long been associated with microsurgical resection of these tumors; however, the application of Gamma knife radiosurgery to the treatment of these tumors by neuro-otologists has not been previously described. SETTING Acoustic Neuroma and Skull Base Surgery Program / Tertiary Referral Center. STUDY DESIGN/PATIENTS/INTERVENTION: Prospective clinical study of all patients treated by the senior author and our gamma knife team beginning in June 2000. MAIN OUTCOME MEASURES Preoperative MRI, audiometry, vestibular testing and facial nerve electromyography were completed. At six-month intervals postoperatively, audiometry, caloric testing and MRI were performed to determine thresholds and speech discrimination ability, vestibular function, and the size of the tumor. RESULTS From June 2000 until March 2004, 38 patients were treated, and these included 33 acoustic neuromas, two meningiomas, one glomus jugulare tumor, and two facial neuromas. Greater than 36 month follow-up was available in 7 patients, > 24 months in 24, > 12 months in 31, and > 6 months in 34 patients. Statistically significant reduction in tumor size was seen over time, and tumor control was achieved in all but two patients. Various patterns of changes in auditory function, both in threshold and speech discrimination were observed in either positive or negative directions. CONCLUSIONS Preliminary experience with Gamma knife radiosurgery indicates that this treatment method represents another option for neuro-otologists to use in managing patients with skull base tumors.
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Affiliation(s)
- P Ashley Wackym
- Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
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20
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Kocher M, Wilms M, Makoski HB, Hassler W, Maarouf M, Treuer H, Voges J, Sturm V, Müller RP. α/β Ratio for arteriovenous malformations estimated from obliteration rates after fractionated and single-dose irradiation. Radiother Oncol 2004; 71:109-14. [PMID: 15066303 DOI: 10.1016/j.radonc.2003.08.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2003] [Revised: 06/05/2003] [Accepted: 08/28/2003] [Indexed: 11/18/2022]
Abstract
BACKGROUND AND PURPOSE Results from single-dose radiosurgery have failed to yield reasonable alpha/beta ratios for obliteration rates of arteriovenous malformations (AVMs) in the framework of the linear-quadratic approach. We used outcome data from single-dose and fractionated radiotherapy for AVM to approach this problem. PATIENTS AND METHODS AVM obliteration rates observed in an updated historical series of fractionated radiotherapy and from six recent series of single-dose stereotactic radiosurgery were analyzed. Reciprocal total doses (1/D) and fraction sizes (d) of isoeffective fractionation schemes were entered into the rearranged form of the linear-quadratic equation: 1/D = (alpha/E) + (beta/E)d, and alpha/beta-ratios were calculated from the parameters of the regression line. RESULTS Fractionated radiotherapy with 20 Gy/4 Gy fractions, 50 Gy/2 Gy fractions and single-dose radiosurgery of approximately 13 Gy were isoeffective with crude obliteration rates of 13%. The analysis yielded an alpha/beta-ratio of 3.5 Gy. For small-sized AVMs (<3 cm), alpha/beta-ratios of 4.6-6.4 Gy were obtained. CONCLUSION These results support the view that radiosurgery for AVM can be understood as a typical late tissue effect with a high fractionation sensitivity. Fractionated radiotherapy is ineffective for AVMs and should be evaluated carefully in other benign targets.
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Affiliation(s)
- Martin Kocher
- Department of Radiation Oncology, University of Cologne, Cologne, Germany
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21
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Kondziolka D, Lunsford LD, Flickinger JC. Comparison of management options for patients with acoustic neuromas. Neurosurg Focus 2003; 14:e1. [PMID: 15669805 DOI: 10.3171/foc.2003.14.5.2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Management options for patients with vestibular schwannomas (acoustic neuromas) include observation, tumor resection, stereotactic radiosurgery, and fractionated radiotherapy. In this report the authors review their 15-year experience with radiosurgery and discuss indications and expectations in relation to the different approaches. They conducted a survey of neurosurgeons to determine management preferences in two different cases of intra- and extra-canalicular tumor presentations. Patient decisions must be based on quality information derived from peer-reviewed literature.
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Affiliation(s)
- Douglas Kondziolka
- Department of Neurological Surgery, Center for Image-Guided Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
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22
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Fukuoka S, Takanashi M, Hojo A, Konishi M, Nakamura H. Gamma Knife Radiosurgery for Acoustic Schwannomas : An Analysis of the Method of Low Dose and Conformal Multiple Shots with Smaller Collimator. ACTA ACUST UNITED AC 2003. [DOI: 10.7887/jcns.12.527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Seiji Fukuoka
- Departments of Neurosurgery, Nakamura Memorial Hospital
| | | | - Atsufumi Hojo
- Departments of Neurosurgery, Nakamura Memorial Hospital
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23
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Abstract
Patients with acoustic neuromas have several treatment options that include observation, surgical resection, stereotactic radiosurgery, and fractionated radiotherapy. Resection is indicated for patients with larger tumors that have caused major neurologic deficits from brain compression. Surgeons perform stereotactic radiosurgery as the main alternative to acoustic tumor resection with the goals of preserved neurologic function and prevention of tumor growth. The long-term outcomes of radiosurgery, particularly with gamma knife technique, have proven its role in the primary or adjuvant management of this disease. Radiotherapy can be offered to selected patients with larger tumors in whom radiosurgery may not be feasible. Patients with neurofibromatosis type-2 pose specific challenges, particularly in regard to preservation of hearing and other cranial nerve function. The primary clinical issues include avoiding tumor-related or treatment-related mortality, prevention of further tumor-related neurologic disability, minimizing treatment risks such as spinal fluid leakage, infections, or cardiopulmonary complications, maintaining regional cranial nerve function (facial, trigeminal, cochlear, and glossopharyngeal/vagal), avoiding hydrocephalus, maintaining quality of life and employment, and reducing cost. All treatment choices should strive to meet all of these goals.
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Affiliation(s)
- Douglas Kondziolka
- Department of Neurological Surgery, University of Pittsburgh, 200 Lothrop Street, Suite B-400, Pittsburgh, PA 15213, USA.
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24
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Hanabusa K, Morikawa A, Murata T, Taki W. Acoustic neuroma with malignant transformation. Case report. J Neurosurg 2001; 95:518-21. [PMID: 11565878 DOI: 10.3171/jns.2001.95.3.0518] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The authors describe the case of a 57-year-old woman who had a right-sided hearing disturbance that had remained untreated for 1 year. The diagnosis was of a right cerebellopontine angle tumor, and the patient underwent its removal via retrosigmoid approach. Pathologically, the tumor was a typical benign neuroma. Growth of residual tumor was detected 4 years after the initial operation, and it was treated with gamma knife surgery (GKS). Six months later, the tumor had grown, and the patient underwent surgery via a combined retrosigmoid-translabyrinthine approach. Abnormal mitotic figures were observed on histological studies, indicating that the tumor had become malignant. Thereafter, the tumor grew rapidly, and the patient died 6.5 years after the initial treatment. It cannot be ruled out that GKS affected the outcome, but the causal sequence was unclear. Because such a patient is rare, documentation of the case was considered clinically important.
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MESH Headings
- Cell Transformation, Neoplastic/pathology
- Cerebellum/pathology
- Cerebellum/radiation effects
- Cerebellum/surgery
- Female
- Humans
- Middle Aged
- Neoplasm Recurrence, Local/diagnosis
- Neoplasm Recurrence, Local/pathology
- Neoplasm Recurrence, Local/surgery
- Neoplasms, Radiation-Induced/diagnosis
- Neoplasms, Radiation-Induced/pathology
- Neoplasms, Radiation-Induced/surgery
- Neuroma, Acoustic/diagnosis
- Neuroma, Acoustic/pathology
- Neuroma, Acoustic/surgery
- Radiosurgery
- Risk Factors
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Affiliation(s)
- K Hanabusa
- Department of Neurosurgery and Pathology, Suzuka General Hospital, Tsu, Mie, Japan.
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25
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Shamisa A, Bance M, Nag S, Tator C, Wong S, Norén G, Guha A. Glioblastoma multiforme occurring in a patient treated with gamma knife surgery. J Neurosurg 2001; 94:816-21. [PMID: 11354416 DOI: 10.3171/jns.2001.94.5.0816] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
✓ Stereotactic radiosurgery is being increasingly advocated as the primary modality for treatment of vestibular schwannomas (VS). This modality has been shown to arrest tumor growth, with few associated short-term morbidities, and with possibly better hearing and facial nerve preservation rates than microsurgery. Radiation-induced oncogenesis has long been recognized, although stereotactic radiosurgery de novo induction of a secondary tumor has never been clearly described. The authors report on a patient with a VS who did not have neurofibromatosis Type 2 and who underwent gamma knife surgery (GKS). This patient required microsurgical removal of the VS within 8 months because of development of a tumor cyst with associated brainstem compression and progressive hydrocephalus. The operation resulted in clinical stabilization and freedom from tumor recurrence.
Seven and a half years after undergoing GKS, the patient presented with symptoms of raised intracranial pressure. Magnetic resonance imaging demonstrated a new ring-enhancing lesion in the inferior temporal lobe adjacent to the area of radiosurgery, which on craniotomy was confirmed to be a glioblastoma multiforme (GBM). Despite additional conventional external-beam radiation to the temporal lobe, the GBM has progressed. Whereas this first reported case of a GBM within the scatter field of GKS does not conclusively prove a direct causal link, it does fulfill all of Cahan's criteria for radiation-induced neoplasia, and demands increased vigilance for the potential long-term complications of stereotactic radiosurgery, and reporting of any similar cases.
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Affiliation(s)
- A Shamisa
- Department of Radiation Oncology, University of Toronto, Ontario, Canada
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26
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Kondziolka D, Lunsford LD, Witt TC, Flickinger JC. The future of radiosurgery: radiobiology, technology, and applications. SURGICAL NEUROLOGY 2000; 54:406-14. [PMID: 11240166 DOI: 10.1016/s0090-3019(00)00348-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D Kondziolka
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213-2592, USA
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27
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Kondziolka D, Lunsford LD, Flickinger JC. Gamma Knife Radiosurgery for Vestibular Schwannomas. Neurosurg Clin N Am 2000. [DOI: 10.1016/s1042-3680(18)30090-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Poen JC, Golby AJ, Forster KM, Martin DP, Chinn DM, Hancock SL, Adler JR. Fractionated stereotactic radiosurgery and preservation of hearing in patients with vestibular schwannoma: a preliminary report. Neurosurgery 1999; 45:1299-305; discussion 1305-7. [PMID: 10598696 DOI: 10.1097/00006123-199912000-00004] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Microsurgery and stereotactic radiosurgery (SRS) for vestibular schwannomas are associated with a relatively high incidence of sensorineural hearing loss. A prospective trial of fractionated SRS was undertaken in an attempt to preserve hearing and minimize incidental cranial nerve injury. METHODS Thirty-three patients with vestibular schwannomas were treated with 2100 cGy in three fractions during a 24-hour period using conventional frame-based linear accelerator radiosurgery. The median tumor diameter was 20 mm (range, 7-42 mm). Baseline and follow-up evaluations included audiometry and contrast-enhanced magnetic resonance imaging. End points were tumor progression, preservation of serviceable hearing, and treatment-related complications. RESULTS Thirty-one patients (32 tumors) were assessable for tumor progression and treatment-related complications and 21 patients for preservation of serviceable hearing, with a median follow-up interval of 2 years (range, 0.5-4.0 yr). Tumor regression or stabilization was documented in 30 patients (97%) and tumor progression in 1 (3%). The patient with tumor progression remains asymptomatic and has not required surgical intervention. Five patients (16%) developed trigeminal nerve injury at a median of 6 months (range, 4-12 mo) after SRS; two of these patients had preexisting trigeminal neuropathy. One patient (3%) developed facial nerve injury (House-Brackmann Class 3) 7 months after SRS. Preservation of useful hearing (Gardner-Robertson Class 1-2) was 77% at 2 years. All patients with pretreatment Gardner-Robertson Class 1 to 2 hearing maintained serviceable (Class 1-3) hearing as of their last follow-up examination. CONCLUSION Three-fraction SRS with a conventional stereotactic frame is feasible and well tolerated in the treatment of acoustic neuroma. This study demonstrates a high rate of hearing preservation and few treatment-related complications among a relatively high-risk patient cohort (tumors >15 mm or neurofibromatosis Type 2). Longer follow-up will be required to assess the durability of tumor control.
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Affiliation(s)
- J C Poen
- Department of Radiation Oncology, Stanford University School of Medicine, California 94305, USA
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Niranjan A, Lunsford LD, Flickinger JC, Maitz A, Kondziolka D. Dose reduction improves hearing preservation rates after intracanalicular acoustic tumor radiosurgery. Neurosurgery 1999; 45:753-62; discussion 762-5. [PMID: 10515468 DOI: 10.1097/00006123-199910000-00003] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE To assess the potential for long-term serviceable hearing preservation in intracanalicular acoustic tumor patients who underwent stereotactic radiosurgery. METHODS Between August 1987 and December 1997, 29 patients with intracanalicular acoustic tumors underwent stereotactic radiosurgery at our center using the Leksell gamma knife (Elekta Instruments, Inc., Atlanta, GA). Fifteen assessable patients had serviceable preradiosurgery hearing (pure tone average, < or = 50 dB; speech discrimination score, > or = 50%). We retrospectively analyzed our hearing results and compared hearing preservation in patients who received a minimal tumor dose of 14 Gy or less versus those who received more than 14 Gy to the tumor margin. RESULTS No perioperative patient morbidity or mortality was observed. Serviceable hearing was preserved in 11 (73%) of 15 assessable patients (actuarial rate, 65%). Long-term follow-up demonstrated serviceable hearing preservation in 10 (100%) of 10 patients who received marginal tumor doses of 14 Gy or less but in only one of five patients who received more than 14 Gy. Preradiosurgery Gardner-Robertson class was preserved in 49%, and testable hearing was present in 68% of patients who had any testable hearing at presentation. Five patients demonstrated improvement in hearing (three had serviceable and two had nonserviceable hearing before radiosurgery). No patient developed a facial or trigeminal neuropathy. Seven of 13 patients with preoperative tinnitus continued to experience tinnitus in follow-up. Episodic vertigo continued in 3 of the 11 patients who presented with vertigo. CONCLUSION Gamma knife radiosurgery (using conformal dose planning, small-beam geometry, and < or = 14 Gy to the margin) prevents tumor growth and achieves excellent hearing preservation rates.
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Affiliation(s)
- A Niranjan
- Department of Neurological Surgery, University of Pittsburgh, Pennsylvania 15213, USA
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30
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Kondziolka D, Levy EI, Niranjan A, Flickinger JC, Lunsford LD. Long-term outcomes after meningioma radiosurgery: physician and patient perspectives. J Neurosurg 1999; 91:44-50. [PMID: 10389879 DOI: 10.3171/jns.1999.91.1.0044] [Citation(s) in RCA: 247] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Stereotactic radiosurgery is a primary or adjuvant management approach used to treat patients with intracranial meningiomas. The goal of radiosurgery is long-term prevention of tumor growth, maintenance of the patient's neurological function, and prevention of new neurological deficits. The object of this study is to report longer-term patient outcomes. METHODS The authors evaluated 99 consecutive patients who underwent radiosurgery for meningioma between 1987 and 1992. Evaluation was performed using serial imaging tests, clinical evaluations, and a patient survey that was administered between 5 and 10 years after radiosurgery. Four patients underwent two radiosurgery procedures for separate meningiomas. The average tumor margin dose was 16 Gy and the median tumor volume was 4.7 ml (range 0.24-24 ml). Fifty-seven patients (57%) had undergone prior resection, of which 12 procedures were considered "total." Five patients received fractionated radiation therapy before radiosurgery. Eighty-nine patients (89%) had skull base tumors. The clinical tumor control rate (no resection required) was 93%. Sixty-one (63%) of 97 tumors became smaller, 31 (32%) remained unchanged in size, and five (5%) were enlarged. Resection was performed in seven patients (7%), six of whom had undergone prior resection. New neurological deficits developed in five patients (5%) 3 to 31 months after radiosurgery. Twenty-seven (42%) of 65 responding patients were employed at the time of radiosurgery and 20 (74%) of these remained so. Radiosurgery was believed to have been "successful" by 67 of 70 patients who completed an outcomes questionnaire 5 to 10 years later. At least one complication was described by nine patients (14%) and in four patients the complications resolved. CONCLUSIONS Five to 10 years after radiosurgery, 96% of surveyed patients believed that radiosurgery provided a satisfactory outcome for their meningioma. Overall, 93% of patients required no other tumor surgery. Incidences of morbidity in this early experience were usually transitory and relatively mild. Radiosurgery provided long-term tumor control associated with high rates of neurological function preservation and patient satisfaction.
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Affiliation(s)
- D Kondziolka
- Department of Neurological Surgery, University of Pittsburgh, Pennsylvania 15213, USA.
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31
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Subach BR, Kondziolka D, Lunsford LD, Bissonette DJ, Flickinger JC, Maitz AH. Stereotactic radiosurgery in the management of acoustic neuromas associated with neurofibromatosis Type 2. J Neurosurg 1999; 90:815-22. [PMID: 10223445 DOI: 10.3171/jns.1999.90.5.0815] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Stereotactically guided radiosurgery is one of the primary treatment modalities for patients with acoustic neuromas (vestibular schwannomas). The goal of radiosurgery is to arrest tumor growth while preserving neurological function. Patients with acoustic neuromas associated with neurofibromatosis Type 2 (NF2) represent a special challenge because of the risk of complete deafness. To define better the tumor control rate and long-term functional outcome, the authors reviewed their 10-year experience in treating these lesions. METHODS Forty patients underwent stereotactic radiosurgery at the University of Pittsburgh, 35 of them for solitary tumors. The other five underwent staged procedures for bilateral lesions (10 tumors, 45 total). Thirteen patients (with 29% of tumors) had undergone a median of two prior resections. The mean tumor volume at radiosurgery was 4.8 ml, and the mean tumor margin dose was 15 Gy (range 12-20 Gy). The overall tumor control rate was 98%. During the median follow-up period of 36 months, 16 tumors (36%) regressed, 28 (62%) remained unchanged, and one (2%) grew. In the 10 patients for whom more than 5 years of clinical and neuroimaging follow-up results were available (median 92 months), five tumors were smaller and five remained unchanged. Surgical resection was performed in three patients (7%) after radiosurgery; only one showed radiographic evidence of progression. Useful hearing (Gardner-Robertson Class I or II) was preserved in six (43%) of 14 patients, and this rate improved to 67% after modifications made in 1992. Normal facial nerve function (House-Brackmann Grade 1) was preserved in 25 (81%) of 31 patients. Normal trigeminal nerve function was preserved in 34 (94%) of 36 patients. CONCLUSIONS Stereotactically guided radiosurgery is a safe and effective treatment for patients with acoustic tumors in the setting of NF2. The rate of hearing preservation may be better with radiosurgery than with other available techniques.
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Affiliation(s)
- B R Subach
- Department of Neurological Surgery, Center for Image-Guided Neurosurgery, University of Pittsburgh Medical Center, Pennsylvania, USA
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32
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Fagan P, Chang P, Turner J. Triton tumor. J Neurosurg 1999; 90:987-9. [PMID: 10223475 DOI: 10.3171/jns.1999.90.5.0987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
BACKGROUND Stereotactic radiosurgery is the principal alternative to microsurgical resection for acoustic neuromas (vestibular schwannomas). The goals of radiosurgery are the long-term prevention of tumor growth, maintenance of neurologic function, and prevention of new neurologic deficits. Although acceptable short-term outcomes have been reported, long-term outcomes have not been well documented. METHODS We evaluated 162 consecutive patients who underwent radiosurgery for acoustic neuromas between 1987 and 1992 by means of serial imaging tests, clinical evaluations, and a survey between 5 and 10 years after the procedure. The average dose of radiation to the tumor margin was 16 Gy, and the mean transverse diameter of the tumor was 22 mm (range, 8 to 39). Resection had been performed previously in 42 patients (26 percent); in 13 patients the tumor represented a recurrence of disease after a previous total resection. Facial function was normal in 76 percent of the patients before radiosurgery, and 20 percent had useful hearing. RESULTS The rate of tumor control (with no resection required) was 98 percent. One hundred tumors (62 percent) became smaller, 53 (33 percent) remained unchanged in size, and 9 (6 percent) became slightly larger. Resection was performed in four patients (2 percent) within four years after radiosurgery. Normal facial function was preserved in 79 percent of the patients after five years (House-Brackmann grade 1), and normal trigeminal function was preserved in 73 percent. Fifty-one percent of the patients had no change in hearing ability. No new neurologic deficits appeared more than 28 months after radiosurgery. An outcomes questionnaire was returned by 115 patients (77 percent of the 149 patients still living). Fifty-four of these patients (47 percent) were employed at the time of radiosurgery, and 37 (69 percent) remained so. Radiosurgery was believed to have been successful by all 30 patients who had undergone surgery previously and by 81 (95 percent) of the 85 who had not. Thirty-six of the 115 patients (31 percent) described at least one complication, which resolved in 56 percent of those cases. CONCLUSIONS Radiosurgery can provide long-term control of acoustic neuromas while preserving neurologic function.
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Affiliation(s)
- D Kondziolka
- Department of Neurological Surgery, University of Pittsburgh, PA 15213, USA
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Comey CH, McLaughlin MR, Jho HD, Martinez AJ, Lunsford LD. Death from a malignant cerebellopontine angle triton tumor despite stereotactic radiosurgery. Case report. J Neurosurg 1998; 89:653-8. [PMID: 9761063 DOI: 10.3171/jns.1998.89.4.0653] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Malignant vestibular nerve tumors are rare: to date, only three cases have been reported in the literature. The authors report a case of an eighth cranial nerve tumor that progressed 5 years after stereotactic radiosurgery. The patient was a 44-year-old man who underwent stereotactic radiosurgery for a 27-mm cerebellopontine angle tumor that was discovered on investigation of tinnitus and hearing loss. He developed facial weakness after 5 years, and repeated imaging revealed tumor enlargement. Despite complete microsurgical excision, the tumor rapidly recurred locally and subsequently disseminated within the neuraxis. The patient died 1 year after tumor progression was detected. Histopathological analysis revealed a malignant spindle cell neoplasm with frequent mitotic figures. The presence of positive rhabdoid elements on immunohistochemical studies confirmed that it was a triton tumor. The authors review the relevant literature concerning the classification and management of malignant vestibular nerve tumors and discuss the implications of tumor progression after stereotactic radiosurgery.
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Affiliation(s)
- C H Comey
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Pennsylvania, USA
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Pollock BE, Lunsford LD, Norén G. Vestibular schwannoma management in the next century: a radiosurgical perspective. Neurosurgery 1998; 43:475-81; discussion 481-3. [PMID: 9733302 DOI: 10.1097/00006123-199809000-00041] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE To discuss how the evolution of vestibular schwannoma radiosurgery, changes in health care delivery, and patient accessibility to medical information will affect the management of vestibular schwannomas in the future. CONCEPT In comparison with microsurgical resection of vestibular schwannomas, radiosurgery has a lower morbidity rate, a similar risk of requiring further surgery, and higher patient satisfaction. As this information becomes more widely available to patients and third-party payors, radiosurgery may replace surgical resection as the preferred management strategy for patients with small to medium sized vestibular schwannomas in the United States. RATIONALE It is estimated that 2500 patients are diagnosed with vestibular schwannomas each year in the United States. Assuming that 80% undergo surgery, 2000 operations are performed annually for newly diagnosed vestibular schwannomas. Data available since 1987 regarding the number of cases for which gamma knife radiosurgery was performed were used to predict the number of patients who will undergo vestibular schwannoma radiosurgery in the future. If the current trend continues, an equal number of patients will undergo surgical resection and radiosurgery to treat their vestibular schwannomas (approximately 1000/yr) sometime between 2005 and 2010. Moreover, it is predicted that by 2020, two-thirds of the patients who are newly diagnosed with vestibular schwannomas will undergo radiosurgery, with surgical resection being reserved for patients with large tumors associated with symptomatic brain stem compression. DISCUSSION Early data regarding vestibular schwannoma radiosurgery predicted an exponential growth curve. Although it is premature to assume that the current trend will continue, it is likely that an ever increasing percentage of patients will undergo radiosurgery as accessibility to this alternative increases, and more data are published regarding long-term tumor growth control rates. If the mathematical model proves to be accurate, then stereotactic radiosurgery will replace surgical resection as the preferred management strategy for the majority of patients with vestibular schwannomas.
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Affiliation(s)
- B E Pollock
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota 55905, USA
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Park YG, Kim EY, Chang JW, Chung SS. Volume changes following gamma knife radiosurgery of intracranial tumors. SURGICAL NEUROLOGY 1997; 48:488-93. [PMID: 9352814 DOI: 10.1016/s0090-3019(97)00186-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The primary goal of radiosurgery for brain tumors is the prevention of further growth. The purpose of this article is to evaluate temporal changes of tumor volume after Gamma Knife radiosurgery on intracranial tumors. METHOD Some 137 patients with 148 intracranial tumors who were treated with Gamma Knife radiosurgery and underwent radiological follow-up were reviewed. The tumors with high radiosensitivities to conventional external radiation were excluded. RESULT The median radiological follow-up period was 12 months (range 1.5-38 months). Volume decreased after radiosurgery in 15 of 45 meningiomas; 10 of 37 schwannomas; 6 of 21 pituitary adenomas; 4 of 15 benign gliomas, including both of 2 subependymal giant cell astrocytomas; and 2 of 8 malignant gliomas. Some 87% of meningiomas and 60% of schwannomas whose volume had decreased began to shrink within 12 months and after 12 months, respectively. Transitory increase in volume preceded shrinkage in 16.2% of schwannomas, 13.3% of benign gliomas, 4.8% of pituitary adenomas, and 2.2% of meningiomas. Marked shrinkage occurred in 17 of 19 metastatic tumors and in all 3 neurocytomas shortly after radiosurgery. Of eight malignant gliomas, five began to grow 2-14 months (median = 5 months) after radiosurgery. CONCLUSION Several points should be considered carefully while following up on patients after radiosurgery: the possibility of transient volume increase, tumor-specific volume change patterns, and the tumor-specific goals of radiosurgery.
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Affiliation(s)
- Y G Park
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea
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Kumazawa H, Kyoumoto R, Matsumoto A, Baba K, Tomoda K, Yamashita T, Tsubura A. A severe combined immunodeficient mouse model for the in vivo study of acoustic schwannoma. Am J Otolaryngol 1996; 17:228-32. [PMID: 8827286 DOI: 10.1016/s0196-0709(96)90086-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- H Kumazawa
- Department of Otolaryngology, Kansai Medical University, Osaka, Japan
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Kondziolka D, Somaza S, Comey C, Lunsford LD, Claassen D, Pandalai S, Maitz A, Flickinger JC. Radiosurgery and fractionated radiation therapy: comparison of different techniques in an in vivo rat glioma model. J Neurosurg 1996; 84:1033-8. [PMID: 8847568 DOI: 10.3171/jns.1996.84.6.1033] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To identify histological changes and effects on survival in rats harboring C6 gliomas, the authors compared radiosurgery to different fractionated radiation therapy regimens including doses of calculated biological equivalence. Rats were randomized to control (54 animals) or treatment groups after implantation of C6 glioma cells into the right frontal brain region. At 14 days, treated rats underwent stereotactic radiosurgery (35 Gy to tumor margin; 22 animals), whole-brain radiation therapy (WBRT) (20 Gy in five fractions; 18 animals), radiosurgery plus WBRT (13 animals), hemibrain radiation therapy (85 Gy in 10 fractions; 16 animals) or single-fraction hemibrain irradiation (35 Gy; 10 animals). When compared to the control group (median survival 22 days), prolonged survival was identified after radiosurgery (p < 0.0001), radiosurgery plus WBRT (p < 0.0001), WBRT alone (p = 0.0002), hemibrain radiation therapy to 85 Gy (p < 0.0001), and 35-Gy hemibrain single-fraction irradiation (p = 0.004). Compared to the control group (mean tumor diameter, 6.8 mm), the tumor size was reduced in all treatment groups except WBRT alone. Reduced tumor cell density was exhibited in rats that underwent radiosurgery (p = 0.006) and radiosurgery plus WBRT (p = 0.009) when compared with rats in the control group, a finding not observed after any fractionated regimen. Increased intratumoral edema was identified after radiosurgery (p = 0.03) and combined treatment (p = 0.05), but not after fractionated radiation therapy or 35-Gy single-fraction hemibrain irradiation. In this animal model, the addition of radiosurgery significantly increased tumor cytotoxicity, potentially at the expense of radiation effects to regional brain. We found no difference in survival benefit or tumor diameter in animals that underwent radiosurgery compared to the calculated biologically equivalent regimen of 10-fraction radiation therapy to 85 Gy. The histological responses after radiosurgery were generally greater than those achieved with biologically equivalent doses of fractionated radiation therapy.
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Affiliation(s)
- D Kondziolka
- Department of Neurological Surgery, University of Pittsburgh, Pennsylvania, USA
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Charabi S, Rygaard J, Klinken L, Tos M, Thomsen J. Subcutaneous growth of human acoustic schwannomas in athymic nude mice. Acta Otolaryngol 1994; 114:399-405. [PMID: 7526595 DOI: 10.3109/00016489409126077] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In order to develop an in vivo model for growth of acoustic schwannomas, we studied tumor specimens from 10 patients, transplanted into a subcutaneous pocket of 67 nude mice. The number of tumors which survived or grew was 63 (94%). Obvious macroscopic growth was observed in 22 (33%), status quo in 28 (42%), and regression of tumor size in 13 (19%). The tumor disappeared in 4 cases (6%). Serial implantation was not possible due to the small amount of neuroma tissue in the surviving tumors. In animals with obvious macroscopic growth, neovascularization was clearly demonstrated. The presence of Schwann cells in the implants was confirmed immunohistochemically. The proliferative activity in the original and implanted tumors was evaluated by the proliferating cell nuclear antigen (PCNA) and Ki-67 nuclear antigen stainings and showed good correlation between primary tumors and implants. This in vivo tumor model will open new opportunities to study the biology of acoustic tumors and to test different therapeutic modalities.
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Affiliation(s)
- S Charabi
- Department of ORL, Head and Neck Surgery, Gentofte University Hospital, Hellerup, Denmark
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Martens F, Verbeke L, Piessens M, Van Vyve M. Stereotactic radiosurgery of vestibular schwannomas with a linear accelerator. ACTA NEUROCHIRURGICA. SUPPLEMENT 1994; 62:88-92. [PMID: 7717144 DOI: 10.1007/978-3-7091-9371-6_18] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The authors describe their initial experience with stereotactic radiosurgery of 22 cases with vestibular schwannomas using a linear accelerator. 14 of them with a follow-up of at least one year were studied. 6-9 months after treatment 86% had central tumour necrosis, 71% tumour shrinkage and none of them evidence of tumour growth 3 patients developed reversible facial nerve impairment, 2 had permanent facial numbness. Hearing diminished in one case out of three with normal hearing and in two out of three with already diminished hearing. Although there is a general consensus that microsurgery is the treatment of choice for these benign tumours, stereotactic radiosurgery challenges this opinion. Stereotactic radiosurgery not only proves to be a valuable alternative for selected cases not suitable for microsurgery, but it is conceivable that it will become the treatment of choice for small vestibular tumours. Tumour control can be obtained in the majority of treated patients with fewer complications and with a higher rate of cranial nerve sparing. This series indicates that linear accelerators can achieve results similar to the Gamma Unit in the treatment of vestibular schwannomas.
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Affiliation(s)
- F Martens
- Department of Neurosurgery, OLV Ziekenhuis, Aalst, Belgium
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Abstract
More than 15,000 patients worldwide have undergone stereotactic radiosurgery since the technique was first described in 1951. Over 6000 of these patients had arteriovenous malformations, usually relatively small. Increasingly, patients with benign and malignant brain tumors have had radiosurgery as an alternative to microsurgical removal. The role of radiosurgery as a tool for functional neurosurgery is being evaluated further. Numerous studies over the past 10 years have examined the benefits and risks of radiosurgery performed with various devices (cyclotron-generated particle beams, the multisource cobalt-60 gamma knife, and modified linear accelerators). As radiosurgical centers continue to proliferate, often without appropriate regulatory review, lamentable lapses in appropriate patient selection, quality assurance, training, and results analysis may ensue. Critical clinical and radiobiological questions (dose, histology, and volume variables) remain to be answered in appropriate studies; these needs can no longer be ignored by governmental funding sources. Stereotactic radiosurgery is a multidisciplinary field, requiring the leadership of neurological surgeons in cooperation with radiation oncologists, radiologists, and medical physicists. For many indications, stereotactic radiosurgery appears poised at both the threshold and at the crossroads. As clinical application progresses, continued dialogue between neurological surgeons and their professional colleagues is necessary to guide proper patient management decisions.
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Affiliation(s)
- L D Lunsford
- Department of Neurological Surgery, University of Pittsburgh Medical Center, Pennsylvania
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