Department of Pathology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
Neuropathology. 2011 Dec;31(6):648-53. doi: 10.1111/j.1440-1789.2011.01214.x. Epub 2011 Apr 11.
Meningiomas usually present as benign tumors corresponding to WHO grade I. The development of the intraparenchymal chordoid variant of meningiomas with cyst formation in the CNS is extremely rare. We report a case of cystic chordoid meningioma in a middle-aged man occurring in the brain parenchyma of the left temporal region. The tumor exhibited a marked peritumoral cyst, with contrast enhancement on MRI in accordance with type 2 of Zee's classification of cystic meningioma. Histologically, the tumor displays a typical chordoid structure with trabeculae or cords of eosinophilic vaculoated cells in the abundant mucoid matrix. Tumor cells are diffusely positive for epithelial membrane antigen (EMA), vimentin and focally positive for D2-40, but lack immunoreactivity for cytokeratin (CK) and GFAP. MIB-1 labeling is low, focally accounting for 2% of the tumor. A diagnosis of primary intraparenchymal cystic chordoid meningioma (WHO grade II) was made. There was no evidence of tumor recurrence during the postoperative 6-month follow-up period. To our knowledge, there is no report describing the radiological and histological characteristics of cystic chordoid meningioma entirely presenting in the brain parenchyma. In addition, the biological behavior and histological differential diagnoses of this tumor are discussed.
脑膜瘤通常表现为良性肿瘤，对应世卫组织分级 I 级。中枢神经系统内出现伴有囊形成的脑实质内脊索样脑膜瘤变体的发展极为罕见。我们报告了一例中年男性左颞叶脑实质内囊性脊索样脑膜瘤病例。肿瘤表现出明显的瘤周囊肿，MRI 增强符合 Zee 分类中囊性脑膜瘤 2 型。组织学上，肿瘤显示出典型的脊索样结构，在丰富的黏液基质中有小梁或嗜酸性空泡化细胞索。肿瘤细胞弥漫性表达上皮膜抗原 (EMA)、波形蛋白，局灶性表达 D2-40，但缺乏细胞角蛋白 (CK) 和 GFAP 的免疫反应性。MIB-1 标记物低，肿瘤的 2%局灶性表达。诊断为原发性脑实质内囊性脊索样脑膜瘤（WHO 分级 II 级）。术后 6 个月随访期间无肿瘤复发证据。据我们所知，没有描述完全在脑实质内表现出的囊性脊索样脑膜瘤的影像学和组织学特征的报告。此外，还讨论了该肿瘤的生物学行为和组织学鉴别诊断。
