title: Primary Intracranial Extra-Axial Anaplastic Ependymomas.
abstract: BACKGROUND
  Ependymomas are usually located in the ventricular system or in the central canal of the spinal cord; intracranial extra-axial ependymomas (IEAEs) are rare. To date, only 17 cases of IEAEs have been reported.
  
  
  METHODS
  We report 2 cases with 3 IEAEs (anaplastic) that were initially misdiagnosed. In Case 1 (47-year-old male), the para-falcine lesion was initially refractory to radiosurgery and gross total resection (GTR) was required due to relentless growth. The lesion had adhered to the falx and was well demarcated from the surrounding cortex. It was then correctly diagnosed as an anaplastic ependymoma on the basis of histopathology, and the patient received radiotherapy. No recurrence was observed after the 53-month follow-up. In Case 2 (30-year-old male), 2 IEAEs underwent staged surgeries and were identified as extra-axial lesions without connection to the ventricular system. Near total resection (NTR) and GTR were achieved in the right temporal and right occipital lesions, respectively, but the patient declined radiotherapy. The residual tumor after NTR regrew rapidly, and aggressive resection was performed followed by radiotherapy. No further recurrence was observed after 28 months. The previous 17 cases were male predominant (76.5%) without correct preoperative diagnoses; no recurrence was observed after total resection in the 9 patients reported in the literature.
  
  
  CONCLUSIONS
  IEAEs are rare and have a wide spectrum of clinical and radiological phenotypes. Preoperative diagnosis is difficult. Favorable outcomes for IEAEs can be achieved by GTR plus radiotherapy. Multiple IEAEs benefit from tailored staged surgical resection plus radiotherapy.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor.
authors.forename: Kai-Bing
authors.initials: KB
authors.lastname: Tian
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor.
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Hao
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor. Electronic address: lidaatlas@aliyun.com.
authors.forename: Da
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People's Republic of China; China National Clinical Research Center for Neurological Diseases; Center of Brain Tumor, Beijing Institute for Brain Disorders; Beijing Key Laboratory of Brian Tumor. Electronic address: zhangjunting2003@aliyun.com.
authors.forename: Jun-Ting
authors.initials: JT
authors.lastname: Zhang
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000473:pathology* / Q000628:therapy*; D003131:Combined Modality Therapy / Q000379:methods; D003937:Diagnosis, Differential; D004806:Ependymoma / Q000473:pathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D018714:Radiotherapy, Adjuvant / Q000379:methods; D016896:Treatment Outcome
keywords: Anaplastic ependymoma; Central nervous system; Extra-axial; Intracranial