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Subselective preoperative embolization for meningiomas

A radiological and pathological assessment

Evelyn Teasdale, James Patterson, Douglas McLellan, and Peter Macpherson

T he use of preoperative embolization of certain meningiomas has been advocated because it can produce tumor necrosis and relatively avascular operative conditions. 1–3 These combine to facilitate surgical removal and so reduce the risks to the patient. The reports recommend the use of superselective catheterization and injection of Gelfoam or liquid embolic material, either with or without balloon occlusion of the proximal vessels. The complexity of this technique makes it time-consuming, and success cannot always be achieved even by the most skilled

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Preoperative identification of meningiomas that are highly likely to recur

Satoshi Nakasu, Yoko Nakasu, Masayuki Nakajima, Masayuki Matsuda, and Jyoji Handa

M eningiomas often recur after seemingly complete removal, 1, 5, 8, 14, 28, 29, 33, 36 although they grow slowly in general and appear to be well circumscribed. Recurrence has been estimated to occur in 9 to 15% of benign meningiomas within 10 years after total removal. 14, 20 Atypical and anaplastic meningiomas reportedly have higher recurrence rates, 38% and 78% respectively, within 5 years after complete removal. 16 Recurrences have often been attributed to incomplete tumor removal and the histological aggressiveness of the tumor; atypical or anaplastic

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Intracranial injection of human meningioma cells in athymic mice: an orthotopic model for meningioma growth

Ian E. McCutcheon, Keith E. Friend, Tammy M. Gerdes, Bing-Mei Zhang, David M. Wildrick, and Gregory N. Fuller

M eningiomas are common tumors, accounting for approximately 22% of all intracranial neoplasms. Although most benign convexity meningiomas can be successfully resected, a large number of benign meningiomas occur in the anatomically complex skull base, where complete resection is difficult to achieve. Because of the frequency with which meningiomas are only partially resectable or recur, it is important to have an animal model to serve as a vehicle for studying the biology of these tumors. For the small percentage (3–5%) of meningiomas that are malignant and the

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Stereotactic radiosurgery for meningiomas

Lawrence S. Chin, Nicholas J. Szerlip, and William F. Regine

Meningiomas are benign tumors attached to the dura that typically have a slow growth rate. After gliomas, they are the most common primary tumor of the brain. They are ideal radiobiological targets because single-fraction radiation has a high biologically effective dose. Furthermore, a highly conformal radiation plan can provide effective treatment to the tumor while sparing the surrounding brain. Meningioma control rates range from 90 to 95%, and the risk of morbidity is low. Radiosurgery is an excellent treatment for asymptomatic, small- to moderate-sized meningiomas. It is also ideal for patients with incompletely resected meningiomas, recurrent meningiomas, and risk factors precluding conventional surgery.

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Medical management of meningioma in the era of precision medicine

Saksham Gupta, Wenya Linda Bi, and Ian F. Dunn

M eningiomas are the most common primary central nervous tumors in adults, comprising more than a third of all brain tumors. Most are WHO grade I, while 15%–20% are considered high grade (WHO grade II or III). While grade I meningiomas largely express an indolent course, high-grade meningiomas are associated with poor prognoses: 10-year overall survival (OS) ranges from 53%–79% for patients with WHO grade II lesions to 14%–34% for those with grade III tumors. Patients with meningioma refractory to conventional surgery or radiation have limited

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Infiltration of the carotid artery by cavernous sinus meningioma

Mark J. Kotapka, Kamal K. Kalia, A. Julio Martinez, and Laligam N. Sekhar

M eningioma is the tumor most frequently involving the cavernous sinus. 12 Encasement of the carotid artery represents one of the greatest obstacles to complete removal of these meningiomas, 2 especially when the artery has been invaded by tumor. Little information exists in the literature on the frequency or extent of carotid artery invasion by meningioma, knowledge that would define the necessity for the use of reconstructive techniques, such as saphenous vein bypass grafting, 11 in such cases. This study was conducted to investigate the frequency and

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Radiation-induced meningiomas: clinical, pathological, cytokinetic, and cytogenetic characteristics

Ossama Al-Mefty, Cahide Topsakal, Svetlana Pravdenkova, Jeffrey R. Sawyer, and Michael J. Harrison

some of the long-term detrimental effects (visual deterioration, panhypopituitarism, organic mental syndrome, vasculoocclusive disease, induction of new tumors, and so forth) are less easily disregarded. Lacassagne 54 first demonstrated tumor formation caused by radiotherapy in an animal model in 1933. Numerous other examples have followed, including reports on gliomas, sarcomas, and meningiomas. Currently, radiation-induced meningiomas are the most common form of radiation-induced neoplasm reported in the literature. With the advent of stereotactic radiation

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Treatment of unresectable meningiomas with the antiprogesterone agent mifepristone

Steven M. Grunberg, Martin H. Weiss, Irving M. Spitz, Jamshid Ahmadi, Alfredo Sadun, Christy A. Russell, Lois Lucci, and Lani L. Stevenson

T he possibility that growth of meningiomas could be influenced by female sex hormones was originally suggested by epidemiological observations. Intracranial meningiomas are found twice as often in women as in men. 14 Several reports 3, 9, 19, 22, 36 have described an increase in meningioma size or symptoms during pregnancy, with resolution after completion or termination of pregnancy, and reappearance during successive pregnancies. An association between meningioma and breast cancer has also been noted. 11, 33 Schoenberg, et al. , 33 studied data from

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Treatment of unresectable skull base meningiomas with somatostatin analogs

Chris Schulz, René Mathieu, Ulrich Kunz, and Uwe Max Mauer

M eningiomas represent around 20% of all intracranial tumors and have a 10-year recurrence rate of 20%–50% despite aggressive surgery and irradiation. 14 The standard surgical treatment for meningiomas is total resection. However, many tumors are not amenable to surgery given their deep location or proximity to delicate structures. 25 The complete removal of skull base meningiomas can be especially difficult when basal vessels and cranial nerves are involved. For inaccessible tumors and those with aggressive histological or clinical features, radiation

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Radiosurgery for large-volume (> 10 cm3) benign meningiomas

Clinical article

Jonathan M. Bledsoe, Michael J. Link, Scott L. Stafford, Paul J. Park, and Bruce E. Pollock

M eningiomas are typically benign and slow-growing tumors that account for 15% of intracranial neoplasms in adults. Although many meningiomas are discovered when they are small, larger tumors remain common because the mass effect they exert generally occurs over many years, and the brain is able to compensate and continue to function normally. Management of larger meningiomas is typically more difficult, especially for tumors located adjacent to the major dural sinuses and skull base regions. 3 , 4 , 13 , 14 Complete resection of meningiomas is the