Department of Pathology, Osaka Red Cross Hospital, Tennoji, Osaka, Japan.
Neuropathology. 2012 Dec;32(6):654-61. doi: 10.1111/j.1440-1789.2012.01298.x. Epub 2012 Feb 28.
We report two cases of ependymoma which showed prominent "granular cell" changes of the cytoplasm. The patients were a 7-year-old boy with a tumor in the cerebellum (case 1) and a 70-year-old man with a tumor in the frontal lobe (case 2). The tumor of case 1 showed a histopathological appearance of ependymoma containing many focal aggregates of large polygonal cells in which the cytoplasm was stuffed with numerous eosinophilic granules. The tumor of case 2 predominantly showed the features of papillary ependymoma, and some tumor cells were swollen and contained similar eosinophilic granules. Intracytoplasmic granules in both tumors were immunoreactive for GFAP and ubiquitin, but not for epithelial membrane antigen, CD68 or mitochondria. Ultrastructurally, they were found as aggregates of membrane-bound, electron-dense, globular structures. Karyotypic analysis of the tumor in case 1 demonstrated 2, 11 and 12 trisomies. Intracytoplasmic eosinophilic granules occasionally occur in astrocytic and oligodendroglial neoplasms, but an appearance of similar granules is very rare in ependymoma. The two cases presented here may represent a new histopathological variant of ependymoma, and the term "granular cell ependymoma" is appropriate for them.
我们报告两例具有明显细胞质“颗粒细胞”改变的室管膜瘤。患者分别为 7 岁男性（病例 1），小脑肿瘤；70 岁男性（病例 2），额叶肿瘤。病例 1 的肿瘤组织学表现为室管膜瘤，包含许多大多边形细胞的局灶性聚集，细胞质充满大量嗜酸性颗粒。病例 2 的肿瘤主要表现为乳头状室管膜瘤的特征，部分肿瘤细胞肿胀，含有类似的嗜酸性颗粒。两例肿瘤细胞内的颗粒均对 GFAP 和泛素呈免疫反应性，但对上皮膜抗原、CD68 或线粒体呈阴性。超微结构显示，它们是膜结合的、电子致密的、球形结构的聚集物。病例 1 肿瘤的核型分析显示存在 2、11 和 12 三体。细胞质内嗜酸性颗粒偶尔出现在星形细胞瘤和少突胶质细胞瘤中，但在室管膜瘤中类似颗粒的出现非常罕见。本文报道的两例可能代表室管膜瘤的一种新的组织病理学亚型，术语“颗粒细胞室管膜瘤”适用于它们。
