Nowak J, Seidel C, Berg F, Pietsch T, Friedrich C, von Hoff K, Rutkowski S, Warmuth-Metz M
From the Reference Center for Neuroradiology (J.N., C.S., F.B., M.W.-M.), University Hospital of Würzburg, Würzburg, Germany
From the Reference Center for Neuroradiology (J.N., C.S., F.B., M.W.-M.), University Hospital of Würzburg, Würzburg, Germany Department of Radiology, Pathology Research (C.S.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
AJNR Am J Neuroradiol. 2014 Oct;35(10):1996-2001. doi: 10.3174/ajnr.A4002. Epub 2014 Jun 19.
Ependymoblastoma is a malignant embryonal tumor that develops in early childhood and has a dismal prognosis. Categorized by the World Health Organization as a subgroup of CNS-primitive neuroectodermal tumor, ependymoblastoma is histologically defined by "ependymoblastic rosettes." Because it is so rare, little is known about specific MR imaging characteristics of ependymoblastoma. We systematically analyzed and discussed MR imaging features of ependymoblastoma in a series of 22 consecutive patients.
Ependymoblastoma cases were obtained from the database of the German multicenter HIT trials between 2002 and 2013. All cases within this study were centrally reviewed for histopathology, MR imaging findings, and multimodal therapy. For systematic analysis of initial MR imaging scans at diagnosis, we applied standardized criteria for reference image evaluation of pediatric brain tumors.
Ependymoblastomas are large tumors with well-defined tumor margins, iso- to hyperintense signal on T2WI, and diffusion restriction. Contrast enhancement is variable, with a tendency to mild or moderate enhancement. Subarachnoid spread is common in ependymoblastoma but can be absent initially. There was a male preponderance (1.75:1 ratio) for ependymoblastoma in our cohort. Mean age at diagnosis was 2.1 years.
With this study, we add the largest case collection to the limited published database of MR imaging findings in ependymoblastoma, together with epidemiologic data. However, future studies are needed to systematically compare MR imaging findings of ependymoblastoma with other CNS-primitive neuroectodermal tumors and ependymoma, to delineate imaging criteria that might help distinguish these pediatric brain tumor entities.
室管膜母细胞瘤是一种发生于儿童早期的恶性胚胎性肿瘤，预后较差。世界卫生组织将其归类为中枢神经系统原始神经外胚层肿瘤的一个亚组，室管膜母细胞瘤在组织学上由“室管膜母细胞玫瑰花结”定义。由于其极为罕见，关于室管膜母细胞瘤的具体磁共振成像特征知之甚少。我们对连续22例患者的室管膜母细胞瘤的磁共振成像特征进行了系统分析和讨论。
室管膜母细胞瘤病例取自2002年至2013年德国多中心HIT试验数据库。本研究中的所有病例均进行了组织病理学、磁共振成像结果及多模式治疗的集中回顾。为了对诊断时的初始磁共振成像扫描进行系统分析，我们应用了小儿脑肿瘤参考图像评估的标准化标准。
室管膜母细胞瘤为大肿瘤，肿瘤边界清晰，在T2加权像上呈等信号至高信号，且有弥散受限。对比增强情况不一，有轻度或中度增强的倾向。蛛网膜下腔播散在室管膜母细胞瘤中很常见，但最初可能不存在。在我们的队列中，室管膜母细胞瘤男性居多（男女比例为1.75:1）。诊断时的平均年龄为2.1岁。
通过本研究，我们在室管膜母细胞瘤磁共振成像结果的有限已发表数据库中增加了最大的病例集，并提供了流行病学数据。然而，未来需要进行研究，以系统地比较室管膜母细胞瘤与其他中枢神经系统原始神经外胚层肿瘤及室管膜瘤的磁共振成像结果，从而确定有助于区分这些小儿脑肿瘤实体的成像标准。
