title: Angiomatous pleomorphic xanthoastrocytoma: a case report and literature review.
abstract: BACKGROUND
  Pleomorphic xanthoastrocytoma is rare, accounting for <1 % of all central nervous system (CNS) neoplasms. Angiomatous pleomorphic xanthoastrocytoma is an extremely rare variant of pleomorphic xanthoastrocytoma, with only six cases reported thus far.
  
  
  METHODS
  A 24-year-old Chinese female patient who presented with seizure and loss of consciousness for 15 min underwent computed tomography and magnetic resonance imaging, which revealed a mass in the left parietal lobe. Histologically, the tumor was characterized by pleomorphic tumor cells and prominent vascularity. The angiomatous region varied, ranging from a sinusoidal pattern to a venous malformation. Focal fibrinoid necrosis, hyalinization, and a moderate infiltration by lymphocytes and plasma cells were visible in the vessel wall. The tumor cells were in close proximity with adjacent small vessels. Capillaries adjacent to or extending between tumor cells were focally observed. Most tumor cells were positive for glial fibrillary acidic protein and oligodendrocyte lineage transcription factor 2. The Ki-67 index was low. Based on the patient's history, clinical data, and pathological findings, she was diagnosed with angiomatous pleomorphic xanthoastrocytoma (WHO grade II).
  
  
  CONCLUSIONS
  This case serves as a reminder to pathologists of the need to be aware of this rare variant of pleomorphic xanthoastrocytoma to avoid a misdiagnosis of this indolent CNS tumor and therefore inappropriate treatment.
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Yue-Feng
authors: YF
authors: Jiang
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China. lyonliuyang@mail.cmu.edu.cn.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China. lyonliuyang@mail.cmu.edu.cn.
authors: Yang
authors: http://orcid.org/0000-0002-6033-0648
authors: Y
authors: Liu
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Ye-Lin
authors: YL
authors: Wang
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Hong-Yi
authors: HY
authors: Cao
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Liang
authors: L
authors: Wang
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Hong-Tao
authors: HT
authors: Xu
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Qing-Chang
authors: QC
authors: Li
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: Xue-Shan
authors: XS
authors: Qiu
authors: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang, 110001, China.|Institute of Pathology and Pathophysiology, China Medical University, Shenyang, 110001, China.
authors: En-Hua
authors: EH
authors: Wang
mesh_terms: D001254:Astrocytoma / Q000000981:diagnostic imaging* / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D016543:Central Nervous System Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen
keywords: Angiomatous variant; BRAF mutation; Pleomorphic xanthoastrocytoma