anaplastic meningioma

anaplastic meningioma

An aggressive form of meningioma, which is defined histologically as having > 20 mitoses/10 high-power fields and/or marked cytologic atypia.
References in periodicals archive ?
Ki-67 proliferative index predicts clinical outcome in patients with atypical or anaplastic meningioma.
Immunohistochemicalstudy of Ki-67 (MIB-1), p53 protein, p21WAF1, and p27KIP1 expression in benign, atypical, and anaplastic meningiomas.
Twenty-seven cases of WHO grade I meningiomas would have increased in grade to atypical meningiomas (WHO grade II), and one atypical meningioma would have increased to anaplastic meningioma (WHO grade III).
Ki-67 proliferative index predicts clinical outcomes in patients with atypical or anaplastic meningioma.
Studies using hydroxyurea, an RNA inhibitor; mifepristone (RU486), a progesterone receptor antagonist; alpha-interferon, a cytokine; and tamoxifen, an estrogen receptor modulator, have shown only modest results and are currently used only in selected cases for atypical and anaplastic meningiomas (Newton, 2007; Wen & Drappatz, 2006).
Results of radiation therapy in atypical and anaplastic meningiomas.
1) The WHO 2007 definition of anaplastic meningioma includes "high mitotic index in excess of 20 per 10 high power fields or histological features of frank malignancy.
The aggressive clinical course and short survival are consistent with both anaplastic meningioma and a high-grade sarcoma.
Anaplastic meningiomas may show carcinoma, sarcoma, or even melanoma-like morphologic patterns, and other primary central nervous system tumors and metastatic malignancies should be excluded in the presence of such poorly differentiated malignant neoplasms.
Anaplastic meningiomas (WHO grade 3) account for <1% all meningiomas and have a much shorter mean survival time, with a 5-year-survival rate of approximately 64%, compared with 95% for atypical meningiomas (2).
Amatya et al (57) studied 146 cases of meningiomas immunohistochemically and reported that the mean MIB-1 LI of benign, atypical, and anaplastic meningiomas was 1.
Immunohistochemical study of Ki-67 (MIB-1), p53 protein, p21WAF1, and p27KIP1 expression in benign, atypical, and anaplastic meningiomas.