title: Calvarial ectopic meningothelial meningioma.
abstract: BACKGROUND
  Meningiomas are the most common benign neoplasm of the brain whereas ectopic presentation, although reported, is rare. Among these ectopic tumors, there are a group of purely intraosseous meningiomas, which usually are diagnosed differentially from common primary osseous tumor such as fibrous dysplasia and osteoid osteoma.
  
  
  METHODS
  We report a 62-year-old female with a history of headaches and 6 months of progressive right parietal bulging, with no neurological signs. Parietal craniotomy was performed with immediate titanium cranioplasty of the parietal convexity. Histopathology exams revealed an ectopic intradiploic meningioma without invasion of cortical layers, with positive staining for progesterone receptors and epithelial membrane antigen.
  
  
  CONCLUSIONS
  Ectopic intraosseous meningiomas remain a rare neoplasm with only a few cases reported. The main theories to justify the unusual topography appear to be embryological remains of neuroectodermal tissue or cellular dedifferentiation. Surgical treatment seems the best curative option.
authors: Resident of Neurosurgery at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: Roberto_vital@hotmail.com.
authors: Roberto Bezerra
authors: RB
authors: Vital
authors: Neurosurgeon at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: pthamamotof@hotmail.com.
authors: Pedro Tadao
authors: PT
authors: Hamamoto Filho
authors: Neurosurgeon at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: relapate@gmail.com.
authors: Renan Luiz
authors: RL
authors: Lapate
authors: Resident of Pathology at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: viniciuszanin@gmail.com.
authors: Vinícius Zanin
authors: VZ
authors: Martins
authors: Pathologist at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: Flavioolima@fmb.unesp.br.
authors: Flávio
authors: F
authors: de Oliveira Lima
authors: Neurosurgeon at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: frromero@ig.com.br.
authors: Flávio Ramalho
authors: FR
authors: Romero
authors: Neurosurgeon at Hospital das Clínicas, UNESP, Botucatu, Brazil. Electronic address: mzanini@fmb.unesp.br.
authors: Marco Antônio
authors: MA
authors: Zanini
keywords: Benign; Brain tumor; Meningioma