Shin Sun Ah, Ahn Bokyung, Kim Seung-Ki, Kang Hyoung Jin, Nobusawa Sumihito, Komori Takashi, Park Sung-Hye
Department of Pathology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
Department of Pathology, Korea University Anam Hospital, Seoul, Korea.
Neuropathology. 2018 Dec;38(6):631-637. doi: 10.1111/neup.12514. Epub 2018 Sep 20.
Astroblastoma is a rare glial neoplasm that occurs mostly in the cerebral hemisphere of children, adolescents and young adults. Although astroblastic perivascular pseudorosettes are unique histopathology of this neoplasm, diagnosis is usually challenging. Recently, it was discovered that the meningioma 1 gene (MN1)-altered pediatric central nervous system high-grade neuroepithelial tumors are actually astroblastomas. This case report presents a rare brainstem astroblastoma, with an unusual immunoprofile: negative for glial fibrillary acidic protein and oligodendrocyte transcription factor 2, but with a robust expression of pancytokeratin and epithelial membrane antigen. The diagnosis was confirmed based on the detection of MN1 rearrangement in a fluorescence in situ hybridization study, in addition to typical histopathology. Here we discuss the diagnostic pitfalls and unclear grading system along with a literature review.
成星形细胞瘤是一种罕见的神经胶质肿瘤，主要发生于儿童、青少年及年轻成人的大脑半球。虽然成星形细胞血管周假菊形团是该肿瘤独特的组织病理学特征，但诊断通常具有挑战性。最近发现，脑膜瘤1基因（MN1）改变的小儿中枢神经系统高级别神经上皮肿瘤实际上就是成星形细胞瘤。本病例报告呈现了一例罕见的脑干成星形细胞瘤，具有不寻常的免疫表型：胶质纤维酸性蛋白和少突胶质细胞转录因子2呈阴性，但全细胞角蛋白和上皮膜抗原呈强表达。除典型的组织病理学检查外，荧光原位杂交研究检测到MN1重排，从而确诊。在此，我们结合文献复习讨论诊断陷阱及不明确的分级系统。
