PDF(Pubmed)
Abstract：
Ependymomas have rarely been described to contain pigment other than melanin, neuromelanin, lipofuscin or a combination. In this case report, we present a pigmented ependymoma in the fourth ventricle of an adult patient and review 16 additional cases of pigmented ependymoma from the literature. A 46-year-old female showed up with hearing loss, headaches, and nausea. Magnetic resonance imaging revealed a 2.5 cm contrast-enhancing cystic mass in the fourth ventricle, which was resected. Intraoperatively, the tumor appeared grey-brown, cystic, and was adherent to the brainstem. Routine histology revealed a tumor with true rosettes, perivascular pseudorosettes and ependymal canals consistent with ependymoma, but also showed chronic inflammation and abundant distended pigmented tumor cells that mimicked macrophages in frozen and permanent sections. The pigmented cells were positive for GFAP and negative for CD163 consonant with glial tumor cells. The pigment was negative for Fontana-Masson, positive for Periodic-acid Schiff and autofluorescent, which coincide with characteristics of lipofuscin. Proliferation indices were low and H3K27me3 showed partial loss. H3K27me 3 is an epigenetic modification to the DNA packaging protein Histone H3 that indicates the tri-methylation of lysine 27 on histone H3 protein. This methylation classification was compatible with a posterior fossa group B ependymoma (EPN_PFB). The patient was clinically well without recurrence at three-month post-operative follow-up appointment. Our analysis of all 17 cases, including the one presented, shows that pigmented ependymomas are most common in the middle-aged with a median age of 42 years and most have a favorable outcome. However, one patient that also developed secondary leptomeningeal melanin accumulations died. Most (58.8%) arise in the 4th ventricle, while spinal cord (17.6%) and supratentorial locations (17.6%) were less common. The age of presentation and generally good prognosis raise the question of whether most other posterior fossa pigmented ependymomas may also fall into the EPN_PFB group, but additional study is required to address that question.
摘要：
很少有人描述室管膜瘤含有黑色素以外的色素，神经黑色素,脂褐素或组合。在这个案例报告中,我们介绍了一名成人患者第四脑室的色素性室管膜瘤，并从文献中回顾了另外16例色素性室管膜瘤。一名46岁的女性出现听力损失，头痛,和恶心。磁共振成像显示第四脑室有一个2.5厘米的对比增强囊性肿块，被切除了。术中,肿瘤呈灰棕色,囊性的,坚持脑干。常规组织学显示肿瘤有真正的玫瑰花结，与室管膜瘤一致的血管周假结膜和室管膜，但也显示出慢性炎症和丰富的扩张色素肿瘤细胞，模仿巨噬细胞在冷冻和永久切片。色素细胞GFAP阳性，CD163阴性，与神经胶质肿瘤细胞一致。色素对Fontana-Masson呈阴性,对周期性酸性希夫和自发荧光呈阳性，这与脂褐素的特征一致。增殖指数低，H3K27me3显示部分损失。H3K27me3是DNA包装蛋白组蛋白H3的表观遗传修饰，表明组蛋白H3蛋白上赖氨酸27的三甲基化。此甲基化分类与后颅窝B组室管膜瘤（EPN_PFB）兼容。患者在术后3个月随访时临床良好，无复发。我们对所有17例病例的分析，包括提交的那个，表明，色素性室管膜瘤在中年人中最常见，中位年龄为42岁，并且大多数具有良好的结局。然而,1例同时出现继发性软脑膜黑色素积累的患者死亡.大多数（58.8％）出现在第四脑室，而脊髓（17.6％）和幕上位置（17.6％）较少见。出现的年龄和总体上良好的预后提出了一个问题，即大多数其他后颅窝色素性室管膜瘤是否也可能属于EPN_PFB组，但是需要额外的研究来解决这个问题。
