Malignant intraventricular meningiomas (IVMs) are very rare with only a few reported cases. A midline search up to December 2020 selected 40 articles for a total of 65 patients. The inclusion criteria were series and case reports in English language, as well as papers written in other languages, but with abstracts written in English. Malignant IVMs at the first diagnosis (group A, 50 patients) and those with anaplastic transformation from previous WHO grades I and II tumors (group B, 15 patients) were separately analyzed. The unique personal case among 1285 meningiomas (0.078%) is also added. Malignant IVMs mainly occur in women (61%) with a median age of 45 years and are mainly located in the lateral ventricle (93%) and trigonal region (74%), with no cases in the fourth ventricle. Irregular borders (80%), heterogeneous enhancement (83%), and perilesional edema (76%) are the most frequent radiological findings. The histology was mainly pure anaplastic (85%), whereas papillary (7%), rhabdoid (5%), and mixed forms (3%) are very rare. The CSF spread was found in 60% of the cases. The prognosis is very dismal, with an overall median survival of 17.5 months after surgery for the anaplastic forms. Malignant IVMs at initial diagnosis (group A) show better overall survival (25 months) than those occurring from anaplastic transformation of lower grade tumors (group B) (10.1 months).

恶性脑室内脑膜瘤 (IVM) 非常罕见，仅有少数报道病例。截至 2020 年 12 月的中线搜索选择了 40 篇文章，共 65 名患者。纳入标准是用英语撰写的系列和病例报告，以及用其他语言撰写但摘要用英语撰写的论文。分别分析了首次诊断时的恶性 IVM（A 组，50 名患者）和先前 WHO I 级和 II 级肿瘤的间变性转化（B 组，15 名患者）。还添加了 1285 例脑膜瘤（0.078%）中唯一的个人病例。恶性IVM主要发生于女性（61%），中位年龄为45岁，主要位于侧脑室（93%）和三角区（74%），第四脑室无病例。不规则边界（80%），异质增强（83%），和病灶周围水肿（76%）是最常见的放射学表现。组织学主要是纯间变性（85%），而乳头状（7%）、横纹肌（5%）和混合型（3%）非常罕见。在 60% 的病例中发现 CSF 扩散。预后非常糟糕，间变性手术后的总体中位生存期为 17.5 个月。初始诊断时的恶性 IVM（A 组）显示出比低级别肿瘤间变性转化（B 组）（10.1 个月）更好的总生存期（25 个月）。间变性手术后 5 个月。初始诊断时的恶性 IVM（A 组）显示出比低级别肿瘤间变性转化（B 组）（10.1 个月）更好的总生存期（25 个月）。间变性手术后 5 个月。初始诊断时的恶性 IVM（A 组）显示出比低级别肿瘤间变性转化（B 组）（10.1 个月）更好的总生存期（25 个月）。