Fractionated stereotactic conformal radiotherapy for large benign skull base meningiomas
© Minniti et al; licensee BioMed Central Ltd. 2011
Received: 27 December 2010
Accepted: 12 April 2011
Published: 12 April 2011
to assess the safety and efficacy of fractionated stereotactic radiotherapy (FSRT) for large skull base meningiomas.
Methods and Materials
Fifty-two patients with large skull base meningiomas aged 34-74 years (median age 56 years) were treated with FSRT between June 2004 and August 2009. All patients received FSRT for residual or progressive meningiomas more than 4 centimeters in greatest dimension. The median GTV was 35.4 cm3 (range 24.1-94.9 cm3), and the median PTV was 47.6 cm3 (range 33.5-142.7 cm3). Treatment volumes were achieved with 5-8 noncoplanar beams shaped using a micromultileaf collimator (MLC). Treatment was delivered in 30 daily fractions over 6 weeks to a total dose of 50 Gy using 6 MV photons. Outcome was assessed prospectively.
At a median follow-up of 42 months (range 9-72 months) the 3-year and 5-year progression-free survival (PFS) rates were 96% and 93%, respectively, and survival was 100%. Three patients required further debulking surgery for progressive disease. Hypopituitarism was the most commonly reported late complication, with a new hormone pituitary deficit occurring in 10 (19%) of patients. Clinically significant late neurological toxicity was observed in 3 (5.5%) patients consisting of worsening of pre-existing cranial deficits.
FSRT as a high-precision technique of localized RT is suitable for the treatment of large skull base meningiomas. The local control is comparable to that reported following conventional external beam RT. Longer follow-up is required to assess long term efficacy and toxicity, particularly in terms of potential reduction of treatment-related late toxicity.
The optimal management of large benign meningiomas of the skull base is challenging. Surgery remains the standard treatment and following apparently complete removal the reported control rates are in the region of 95% at 5 years and 90% at 10 years [1–14]. However, a significant subset of meningiomas, especially large tumors involving the cavernous sinus, the petroclival region, and the brainstem cannot be completely resected for the risk of significant morbidity [1, 3–6, 9]. In such patients incomplete removal of tumor with preservation of the involved cranial nerves may result in improved neurological function and temporary local control, although progression on long-term follow-up is reported in up to 80% of patients [2, 8, 13].
Local control following partial resection of benign meningiomas and at the time of recurrence can be improved with conventional fractionated external beam radiotherapy (RT), with a reported 10-year progression-free survival in the region of 75-90% [15–17]. More recently, stereotactic radiation techniques in form of stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) have been developed as accurate techniques that can deliver more localized irradiation with a steeper dose gradient between the tumor and the surrounding normal tissue, and consequently reducing the volume of normal brain irradiated to high radiation doses. Both techniques have been reported as an effective treatment in several benign skull base tumors including pituitary adenomas [18, 19], acoustic neuromas [20, 21], craniopharyngiomas [22, 23] and meningiomas .
Although in many centers SRS is the preferred treatment option for patients with small to moderate recurrent or enlarging skull base meningiomas, fractionated RT is often performed for larger tumors close to critical structures because of the radiobiological advantage of dose fractionation in reducing the risk of post-radiation long-term complications. In this study, we report the experience with FSRT at our center for patients with large residual or progressive skull base meningiomas.
Patients and Methods
Clinical characteristics of 52 patients with large skull base meningiomas treated with fractionated stereotactic radiotherapy
17 M\35 F
Median age (range)
56 yrs (34-74)
Number of surgeries
Gross tumour volume (GTV)
24.1 - 94.9 cm3
Planning target volume (PTV)
33.5 -142.7 cm3
Cranial deficits at presentation in 52 patients with large skull base benign meningiomas
(median follow-up 34 months)
SCRT technique and dose prescription
The FSRT technical details and procedure using the BrainLab stereotactic mask fixation system have been previously reported . The gross tumor volume (GTV) was delineated on the basis of the contrast-enhancing tumor demonstrated on T1-weighted MRI fused with the simulation CT images. CTV was considered the same as GTV. The planning target volume (PTV) was generated by the geometric expansion of GTV plus 2-3 mm. For the last 18 patients the 3-D margin was reduced to 2 mm. The median GTV was 35.4 cm3 (range 24.1-94.9 cm3). The PTV was 47.6 cm3 (range 33.5-142.7 cm3). Treatment volumes were achieved with 5-8 noncoplanar beams shaped using a micromultileaf collimator (MLC). Plans were prescribed at the isocentre according to ICRU 50 criteria with PTV covered by the 95% isodose in 3-D. To assess the accuracy of relocation, the isocentre position was verified with a second CT scan performed just prior to the start of treatment. The tolerance of relocation had to be < 1.5 mm in any direction. Daily portal images acquired at 0 and 90° through the isocenter were obtained for each patient during the treatment. All patients were treated on a 6-MV LINAC with a 120 leaf MLC (Varian Clinac 600 DBX) and received a dose of 50 Gy in 30 fractions over 6 weeks.
Follow-up and data analysis
A clinical assessment of neurological status and tolerance to treatment was performed every six months. An MRI scan was performed every 6 months for the first 2 years and thereafter every 12 months. Tumor control was defined by the absence of radiological tumor progression. Pituitary function was assessed by complete basal hormonal assessment and dynamic testing, as appropriate, in an endocrine clinic. Vision was assessed by serial ophthalmologic examinations. Tumor control and overall survival were measured from the start of FSRT. Univariate analysis and multivariate Cox proportional hazards regression model were used to test the effect of prognostic factors on tumor control.
Tumor control and survival
Neurological deficits were present in 43 (82%) patients. After FSRT 11 (20%) patients had a clinical improvement of neurological deficits (Table 2). Vision improved in 7 patients and cranial nerve function in 5 patients. The optic chiasm was included in the PTV of the majority of patients (n = 36) and received the prescribed dose of 50 Gy. Three patients deteriorated without evidence of tumor progression on imaging. One patient had a slight worsening of vision and two progressive hearing loss. Seven patients had a transient mild visual deterioration (n = 4) and a worsening of pre-existing 7th (n = 1) and 5th (n = 2) nerve palsy during or shortly after treatment, with full recovery after a short course of corticosteroids.
Acute and late toxicity
All patients noted transient localized alopecia at the beam entrance with full subsequent recovery of hair growth. Tiredness occurred in 14 (27%) patients, lasting for 4-8 weeks after FSRT. Transient headache occurred in 6 patients. One patient had an increase in seizure frequency. A development of new or worsening of pre-existing hypopituitarism occurred in 10 (19%) patients after a median follow-up of 36 months, requiring hormone replacement therapy with gonadal steroids and growth hormone in 7 patients, GH replacement in 2 patients, and thyroxine and hydrocortisone in 4 patients. The pituitary fossa contained residual tumor in 27 patients, and was included in the PTV. New clinically apparent neurocognitive dysfunction (Grade II RTOG memory impairment) was reported in one patient. No radiation necrosis, cerebrovascular accidents and second tumors were reported.
Summary of main results on published studies on the conformal radiotherapy and FSRT of skull base meningiomas
Goldsmith et al., 1994
89 at 5 and 77 at 10 years
Maire et al., 1995
Peele et al., 1996
Condra et al.,1997
87 at 15 years
Connell et al., 1999
76 at 5 years
Maguire et al., 1999
8 at 8 years
Nutting et al., 1999
92 at 5 and 83 at 10 years
Vendrely et al., 1999
79 at 5 years
Dufour et al., 2001
93 at 5 and 10 years
Pourel et al., 2001
95 at 5 years
Mendenhall et al., 2003
95 at 5, 92 at 10 and 15 years
Debus et al., 2001
Jalali et al., 2002
Lo et al., 2002
Torres et al., 2003
Selch et al., 2004
100 at 3 years
Milker-Zabel et al., 2005
90.5 at 5 and 89 at 10 years
Henzel et al., 2006
Brell et al., 2006
93 at 4 years
Hamm et al., 2008
97 at 5 years
Litré et al., 2009
94 at 3 years
Metellus et al., 2010
98 at 5 and 96 at 10 years
Tanzler E et al., 2010
97 at 5 and 96 at 10 years
The external beam radiation dose for meningioma that represents the best balance of tumor control and a low complication rate has not been defined. Most of published series show no significant difference on tumor control with the use of doses ranging between 50 and 60 Gy, however a dose < 50 Gy has been associated with higher recurrence rates [15, 27, 33]. The present results, with a tumor control of 90% at 5 years, suggest that a dose of 50 Gy in 30 fractions may achieve a good local tumor control with acceptable toxicity in large skull base meningiomas.
SRS represents an effective and safe alternative treatment option for patients with skull base meningiomas. At doses of 12-16 Gy the reported actuarial 5-year and 10-year tumor local control rates are in the range of 90-95% and 80-85%, as shown in some recent large series [46–58]; however, larger tumors are associated with worse long-term local control and increased toxicity [49, 54, 55]. DiBiase et al  reported a significant higher 5-year tumor control in patients with meningiomas < 10 ml than those with larger tumors (92% vs 68%, p = 0.038). In a large series of 972 patients with meningioma treated with Gamma Knife SRS using a median dose to the tumor margin of 13 Gy local control was negatively correlated with increasing volume (p = 0.01), and a similar trend was observed with disease-specific survival (p = 0.11) . In a retrospective review of 116 patients treated with SRS for meningiomas > 10 cm3 in volume at a dose of 15 Gy, Bledsoe et al  reported a local control of 92% at 7 years, although complications occurred in 18% of patients with skull base tumors. Interestingly, Iwai et al  using a median marginal dose ranging from 8 to 12 Gy showed a progression-free survival of 93% and 83% at 5 and 10 years in 108 patients with skull base meningiomas treated with Gamma Knife SRS; permanent neurological deficits occurred in 6% of patients. Although the use of radiosurgical doses less than 12 Gy may represent a promising approach in patients with large meningiomas, the reported favourable outcome needs to be confirmed in future studies. Currently, results from published series suggest that FSRT is a better treatment option in such patients based on its proven efficacy and safety.
Hypopituitarism was the most commonly reported late complication. A new pituitary hormone deficit requiring hormone replacement occurred in 19% of patients. Late neurological toxicity was observed in 7% of patients and consisted of worsening of pre-existing cranial deficits in 3 patients and mild neurocognitive dysfunction in one patient. A neurological improvement was observed in 19% of patients; vision remained stable in 46 patients and improved in 7 patients with visual impairment. Since the late effects of radiotherapy in terms of normal tissue damage expressed as radiation optic neuropathy occur usually within 1-5 years of treatment, the low incidence of radiation-induced optic neuropathy and others cranial nerve deficits at a median follow-up of 42 months provide some reassurance about the safety of the present dose and technique for large skull base meningiomas. The present and some other recent series on FSRT [34–45] and conformal RT [15, 17] definitely contradict the historical perception of unresponsiveness of meningiomas as well as the considerably concern of high late morbidity following the radiation treatment for benign brain tumors, which was primarily based on old reports where radiation was delivered with orthovoltage machines.
We conclude that FSRT is a high precise and safe treatment for the majority of large skull base meningiomas, with a control of tumor growth at 5 years comparable to that seen following conventional fractionated radiotherapy. For patients with large skull base meningiomas a combination of conservative surgery and postoperative irradiation should always be considered when an attempt to complete resection carries unacceptable risks of neurological deficits. The use of 2-3 mm margin from GTV to generate PTV with FSRT permits a more localized irradiation compared with conventional radiotherapy. Minimizing the radiation dose to normal brain FSRT may reduce the risk of developing late radiation-induced toxicity; however, the potential benefit in reducing long term treatment complications while maintaining a high efficacy will require longer follow-up of a large cohort of patients.
We are grateful to Mr. Davide Mollo for his excellent technical assistance during the study.
- Sekhar LN, Jannetta PJ: Cerebellopontine angle meningiomas. Microsurgical excision and follow-up results. J Neurosurg 1984, 60: 500-5. 10.3171/jns.1984.60.3.0500View ArticlePubMedGoogle Scholar
- Mirimanoff RO, Dosoretz DE, Linggood RM, Ojemann RG, Martuza RL: Meningioma: analysis of recurrence and progression following neurosurgical resection. J Neurosurg 1985, 62: 18-24. 10.3171/jns.1985.62.1.0018View ArticlePubMedGoogle Scholar
- Kallio M, Sankila R, Hakulinen T, Jääskeläinen J: Factors affecting operative and excess long-term mortality in 935 patients with intracranial meningioma. Neurosurgery 1992, 31: 2-12. 10.1227/00006123-199207000-00002View ArticlePubMedGoogle Scholar
- DeMonte F, Smith HK, al-Mefty O: Outcome of aggressive removal of cavernous sinus meningiomas. J Neurosurg 1994, 81: 245-51. 10.3171/jns.1994.81.2.0245View ArticlePubMedGoogle Scholar
- Cusimano MD, Sekhar LN, Sen CN, et al.: The results of surgery for benign tumors of the cavernous sinus. Neurosurgery 1995, 37: 1-9. 10.1227/00006123-199507000-00001View ArticlePubMedGoogle Scholar
- Couldwell WT, Fukushima T, Giannotta SL, Weiss MH: Petroclival meningiomas: surgical experience in 109 cases. J Neurosurg 1996, 84: 20-8. 10.3171/jns.1996.84.1.0020View ArticlePubMedGoogle Scholar
- De Jesús O, Sekhar LN, Parikh HK, Wright DC, Wagner DP: Long-term follow-up of patients with meningiomas involving the cavernous sinus: recurrence, progression, and quality of life. Neurosurgery 1996, 39: 915-9.View ArticlePubMedGoogle Scholar
- Mathiesen T, Lindquist C, Kihlström L, Karlsson B: Recurrence of cranial base meningiomas. Neurosurgery 1996, 39: 2-7. 10.1097/00006123-199607000-00002View ArticlePubMedGoogle Scholar
- O'Sullivan MG, van Loveren HR, Tew JM: The surgical resectability of meningiomas of the cavernous sinus. Neurosurgery 1997, 40: 238-44.View ArticlePubMedGoogle Scholar
- Stafford SL, Perry A, Suman VJ, et al.: Primarily resected meningiomas: outcome and prognostic factors in 581 Mayo Clinic patients, 1978 through 1988. Mayo Clin Proc 1998, 73: 936-42. 10.4065/73.10.936View ArticlePubMedGoogle Scholar
- Abdel-Aziz KM, Froelich SC, Dagnew E, et al.: Large sphenoid wing meningiomas involving the cavernous sinus: conservative surgical strategies for better functional outcomes. Neurosurgery 2004, 54: 1375-83. 10.1227/01.NEU.0000125542.00834.6DView ArticlePubMedGoogle Scholar
- Shrivastava RK, Sen C, Costantino PD, Della Rocca R: Sphenoorbital meningiomas: surgical limitations and lessons learned in their long-term management. J Neurosurg 2005, 103: 491-7. 10.3171/jns.2005.103.3.0491View ArticlePubMedGoogle Scholar
- Sindou M, Wydh E, Jouanneau E, Nebbal M, Lieutaud T: Long-term follow-up of meningiomas of the cavernous sinus after surgical treatment alone. J Neurosurg 2007, 107: 937-44. 10.3171/JNS-07/11/0937View ArticlePubMedGoogle Scholar
- Natarajan SK, Sekhar LN, Schessel D, Morita A: Petroclival meningiomas: multimodality treatment and outcomes at long-term follow-up. Neurosurgery 2007, 60: 965-79. 10.1227/01.NEU.0000255472.52882.D6View ArticlePubMedGoogle Scholar
- Goldsmith BJ, Wara WM, Wilson CB, Larson DA: Postoperative irradiation for subtotally resected meningiomas. A retrospective analysis of 140 patients treated from 1967 to 1990. J Neurosurg 1994, 80: 195-201. 10.3171/jns.1994.80.2.0195View ArticlePubMedGoogle Scholar
- Nutting C, Brada M, Brazil L, et al.: Radiotherapy in the treatment of benign meningioma of the skull base. J Neurosurg 1999, 90: 823-7. 10.3171/jns.1999.90.5.0823View ArticlePubMedGoogle Scholar
- Mendenhall WM, Morris CG, Amdur RJ, Foote KD, Friedman WA: Radiotherapy alone or after subtotal resection for benign skull base meningiomas. Cancer 2003, 98: 1473-82. 10.1002/cncr.11645View ArticlePubMedGoogle Scholar
- Brada M, Ajithkumar TV, Minniti G: Radiosurgery for pituitary adenomas. Clin Endocrinol (Oxf) 2004, 61: 531-43. 10.1111/j.1365-2265.2004.02138.xView ArticleGoogle Scholar
- Minniti G, Traish D, Ashley S, Gonsalves A, Brada M: Fractionated stereotactic conformal radiotherapy for secreting and nonsecreting pituitary adenomas. Clin Endocrinol (Oxf) 2006, 64: 542-8. 10.1111/j.1365-2265.2006.02506.xView ArticleGoogle Scholar
- Andrews DW, Suarez O, Goldman HW, et al.: Stereotactic radiosurgery and fractionated stereotactic radiotherapy for the treatment of acoustic schwannomas: comparative observations of 125 patients treated at one institution. Int J Radiat Oncol Biol Phys 2001, 50: 1265-78. 10.1016/S0360-3016(01)01559-0View ArticlePubMedGoogle Scholar
- Combs SE, Welzel T, Schulz-Ertner D, Huber PE, Debus J: Differences in clinical results after LINAC-based single-dose radiosurgery versus fractionated stereotactic radiotherapy for patients with vestibular schwannomas. Int J Radiat Oncol Biol Phys 2010, 76: 193-200. 10.1016/j.ijrobp.2009.01.064View ArticlePubMedGoogle Scholar
- Minniti G, Saran F, Traish D, et al.: Fractionated stereotactic conformal radiotherapy following conservative surgery in the control of craniopharyngiomas. Radiother Oncol 2007, 82: 90-5. 10.1016/j.radonc.2006.11.005View ArticlePubMedGoogle Scholar
- Minniti G, Esposito V, Amichetti M, Enrici RM: The role of fractionated radiotherapy and radiosurgery in the management of patients with craniopharyngioma. Neurosurg Rev 2009, 32: 125-32. 10.1007/s10143-009-0186-4View ArticlePubMedGoogle Scholar
- Minniti G, Amichetti M, Enrici RM: Radiotherapy and radiosurgery for benign skull base meningiomas. Radiat Oncol 2009, 4: 42. 10.1186/1748-717X-4-42PubMed CentralView ArticlePubMedGoogle Scholar
- Minniti G, Valeriani M, Clarke E, et al.: Fractionated stereotactic radiotherapy for skull base tumors: analysis of treatment accuracy using a stereotactic mask fixation system. Radiat Oncol 2010, 5: 1. 10.1186/1748-717X-5-1PubMed CentralView ArticlePubMedGoogle Scholar
- Maire JP, Caudry M, Guérin J, et al.: Fractionated radiation therapy in the treatment of intracranial meningiomas: local control, functional efficacy, and tolerance in 91 patients. Int J Radiat Oncol Biol Phys 1995, 33: 315-21. 10.1016/0360-3016(94)00661-4View ArticlePubMedGoogle Scholar
- Peele KA, Kennerdell JS, Maroon JC, et al.: The role of postoperative irradiation in the management of sphenoid wing meningiomas. A preliminary report. Ophthalmology 1996, 103: 1761-6.View ArticlePubMedGoogle Scholar
- Condra KS, Buatti JM, Mendenhall WM, Friedman WA, Marcus RB, Rhoton AL: Benign meningiomas: primary treatment selection affects survival. Int J Radiat Oncol Biol Phys 1997, 39: 427-36. 10.1016/S0360-3016(97)00317-9View ArticlePubMedGoogle Scholar
- Connell PP, Macdonald RL, Mansur DB, Nicholas MK, Mundt AJ: Tumor size predicts control of benign meningiomas treated with radiotherapy. Neurosurgery 1999, 44: 1194-9. 10.1097/00006123-199906000-00018PubMedGoogle Scholar
- Maguire PD, Clough R, Friedman AH, Halperin EC: Fractionated external-beam radiation therapy for meningiomas of the cavernous sinus. Int J Radiat Oncol Biol Phys 1999, 44: 75-9. 10.1016/S0360-3016(98)00558-6View ArticlePubMedGoogle Scholar
- Vendrely V, Maire JP, Darrouzet V, et al.: Fractionated radiotherapy of intracranial meningiomas: 15 years' experience at the Bordeaux University Hospital Center. Cancer Radiother 1999, 3: 311-7.View ArticlePubMedGoogle Scholar
- Dufour H, Muracciole X, Métellus P, Régis J, Chinot O, Grisoli F: Long-term tumor control and functional outcome in patients with cavernous sinus meningiomas treated by radiotherapy with or without previous surgery: is there an alternative to aggressive tumor removal? Neurosurgery 2001, 48: 285-94. 10.1097/00006123-200102000-00006PubMedGoogle Scholar
- Pourel N, Auque J, Bracard S, et al.: Efficacy of external fractionated radiation therapy in the treatment of meningiomas: a 20-year experience. Radiother Oncol 2001, 61: 65-70. 10.1016/S0167-8140(01)00391-7View ArticlePubMedGoogle Scholar
- Debus J, Wuendrich M, Pirzkall A, et al.: High efficacy of fractionated stereotactic radiotherapy of large base-of-skull meningiomas: long-term results. J Clin Oncol 2001, 19: 3547-53.PubMedGoogle Scholar
- Jalali R, Loughrey C, Baumert B, et al.: High precision focused irradiation in the form of fractionated stereotactic conformal radiotherapy (SCRT) for benign meningiomas predominantly in the skull base location. Clin Oncol (R Coll Radiol) 2002, 14: 103-9.View ArticleGoogle Scholar
- Lo SS, Cho KH, Hall WA, et al.: Single dose versus fractionated stereotactic radiotherapy for meningiomas. Can J Neurol Sci 2002, 29: 240-8.View ArticlePubMedGoogle Scholar
- Torres RC, Frighetto L, De Salles AA, et al.: Radiosurgery and stereotactic radiotherapy for intracranial meningiomas. Neurosurg Focus 2003, 14: e5. 10.3171/foc.2003.14.5.6View ArticlePubMedGoogle Scholar
- Selch MT, Ahn E, Laskari A, et al.: Stereotactic radiotherapy for treatment of cavernous sinus meningiomas. Int J Radiat Oncol Biol Phys 2004, 59: 101-11. 10.1016/j.ijrobp.2003.09.003View ArticlePubMedGoogle Scholar
- Milker-Zabel S, Zabel A, Schulz-Ertner D, Schlegel W, Wannenmacher M, Debus J: Fractionated stereotactic radiotherapy in patients with benign or atypical intracranial meningioma: long-term experience and prognostic factors. Int J Radiat Oncol Biol Phys 2005, 61: 809-16. 10.1016/j.ijrobp.2004.07.669View ArticlePubMedGoogle Scholar
- Brell M, Villà S, Teixidor P, et al.: Fractionated stereotactic radiotherapy in the treatment of exclusive cavernous sinus meningioma: functional outcome, local control, and tolerance. Surg Neurol 2006, 65: 28-33. 10.1016/j.surneu.2005.06.027View ArticlePubMedGoogle Scholar
- Henzel M, Gross MW, Hamm K, et al.: Significant tumor volume reduction of meningiomas after stereotactic radiotherapy: results of a prospective multicenter study. Neurosurgery 2006, 59: 1188-94. 10.1227/01.NEU.0000245626.93215.F6View ArticlePubMedGoogle Scholar
- Hamm K, Henzel M, Gross MW, Surber G, Kleinert G, Engenhart-Cabillic R: Radiosurgery/stereotactic radiotherapy in the therapeutical concept for skull base meningiomas. Zentralbl Neurochir 2008, 69: 14-21. 10.1055/s-2007-992138View ArticlePubMedGoogle Scholar
- Litré CF, Colin P, Noudel R, et al.: Fractionated stereotactic radiotherapy treatment of cavernous sinus meningiomas: a study of 100 cases. Int J Radiat Oncol Biol Phys 2009, 74: 1012-7.View ArticlePubMedGoogle Scholar
- Metellus P, Batra S, Karkar S, et al.: Fractionated Conformal Radiotherapy in the Management of Cavernous Sinus Meningiomas: Long-Term Functional Outcome and Tumor Control at a Single Institution. Int J Radiat Oncol Biol Phys 2010,78(3):836-43. 10.1016/j.ijrobp.2009.08.006View ArticlePubMedGoogle Scholar
- Tanzler E, Morris CG, Kirwan JM, Amdur RJ, Mendenhall WM: Outcomes of WHO Grade I Meningiomas Receiving Definitive or Postoperative Radiotherapy. Int J Radiat Oncol Biol Phys 2010, in press.Google Scholar
- Stafford SL, Pollock BE, Foote RL, et al.: Meningioma radiosurgery: tumor control, outcomes, and complications among 190 consecutive patients. Neurosurgery 2001, 49: 1029-37. 10.1097/00006123-200111000-00001PubMedGoogle Scholar
- Nicolato A, Foroni R, Alessandrini F, Maluta S, Bricolo A, Gerosa M: The role of Gamma Knife radiosurgery in the management of cavernous sinus meningiomas. Int J Radiat Oncol Biol Phys 2002, 53: 992-1000. 10.1016/S0360-3016(02)02802-XView ArticlePubMedGoogle Scholar
- Lee JY, Niranjan A, McInerney J, Kondziolka D, Flickinger JC, Lunsford LD: Stereotactic radiosurgery providing long-term tumor control of cavernous sinus meningiomas. J Neurosurg 2002, 97: 65-72. 10.3171/jns.2002.97.1.0065View ArticlePubMedGoogle Scholar
- DiBiase SJ, Kwok Y, Yovino S, et al.: Factors predicting local tumor control after gamma knife stereotactic radiosurgery for benign intracranial meningiomas. Int J Radiat Oncol Biol Phys 2004, 60: 1515-19. 10.1016/j.ijrobp.2004.05.073View ArticlePubMedGoogle Scholar
- Pollock BE, Stafford SL: Results of stereotactic radiosurgery for patients with imaging defined cavernous sinus meningiomas. Int J Radiat Oncol Biol Phys 2005, 62: 1427-31. 10.1016/j.ijrobp.2004.12.067View ArticlePubMedGoogle Scholar
- Kollová A, Liscák R, Novotný J, Vladyka V, Simonová G, Janousková L: Gamma Knife surgery for benign meningioma. J Neurosurg 2007, 107: 325-36.View ArticlePubMedGoogle Scholar
- Hasegawa T, Kida Y, Yoshimoto M, Koike J, Iizuka H, Ishii D: Long-term outcomes of Gamma Knife surgery for cavernous sinus meningioma. J Neurosurg 2007, 107: 745-51. 10.3171/JNS-07/10/0745View ArticlePubMedGoogle Scholar
- Iwai Y, Yamanaka K, Ikeda H: Gamma Knife radiosurgery for skull base meningioma: long-term results of low-dose treatment. J Neurosurg 2008, 109: 804-10. 10.3171/JNS/2008/109/11/0804View ArticlePubMedGoogle Scholar
- Kondziolka D, Mathieu D, Lunsford LD, et al.: Radiosurgery as definitive management of intracranial meningiomas. Neurosurgery 2008, 62: 53-8. 10.1227/01.NEU.0000311061.72626.0DView ArticlePubMedGoogle Scholar
- Bledsoe JM, Link MJ, Stafford SL, Park PJ, Pollock BE: Radiosurgery for large-volume (> 10 cm3) benign meningiomas. J Neurosurg 2010, 112: 951-6. 10.3171/2009.8.JNS09703View ArticlePubMedGoogle Scholar
- Flannery TJ, Kano H, Lunsford LD et al: Long-term control of petroclival meningiomas through radiosurgery. J Neurosurg 2010, 112: 957-64. 10.3171/2009.8.JNS09695View ArticlePubMedGoogle Scholar
- Nakaya K, Niranjan A, Kondziolka D, et al.: Gamma knife radiosurgery for benign tumors with symptoms from brainstem compression. Int J Radiat Oncol Biol Phys 2010, 77: 988-95. 10.1016/j.ijrobp.2009.06.089View ArticlePubMedGoogle Scholar
- Zada G, Pagnini PG, Yu C, et al.: Long-term Outcomes and Patterns of Tumor Progression After Gamma Knife Radiosurgery for Benign Meningiomas. Neurosurgery 2010, 67: 322-9. 10.1227/01.NEU.0000371974.88873.15View ArticlePubMedGoogle Scholar
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