title: Retrobulbar primitive neuroectodermal tumor in a squirrel monkey (Saimiri sciureus).
abstract: BACKGROUND
  A 2.8-year-old female captive-bred common squirrel monkey (Saimiri sciureus) showed exophthalmos of the right eye, and the eye was surgically enucleated. A tumor mass was found in the eye.
  
  
  METHODS
  Formalin-fixed tumor samples were examined histopathologically and immunohistochemically for diagnosis.
  
  
  RESULTS
  The retrobulbar tumor mass adhered to the sclera and infiltrated the choroid. Histopathologically, tumor cells were pleomorphic, arranged in a sheet pattern, and mimicked primitive neuroectodermal cells. The tumor cells were strongly positive for precursor neuronal cell markers (beta III tubulin, neuron-specific enolase, vimentin, nestin, doublecortin, oligo2, and S-100), but negative for mature cell markers (cytokeratin, neurofilament, and glial fibrillary acidic protein) and a retinoblastoma marker (rhodopsin).
  
  
  CONCLUSIONS
  This is the first reported case for the retrobulbar location of primitive neuroectodermal tumor in non-human primates.
authors: Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand. wijit.k@chula.ac.th
authors: Wijit
authors: W
authors: Banlunara
authors: Masaya
authors: M
authors: Tsuboi
authors: Kazuyuki
authors: K
authors: Uchida
authors: Piyaporn
authors: P
authors: Kongmekee
authors: Piyanee
authors: P
authors: Ngamsuk
authors: Hiroyuki
authors: H
authors: Nakayama
mesh_terms: D000818:Animals; D005260:Female; D006651:Histocytochemistry / Q000662:veterinary; D008992:Monkey Diseases / Q000473:pathology* / Q000601:surgery; D018242:Neuroectodermal Tumors, Primitive / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D009918:Orbital Neoplasms / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D019315:Retrobulbar Hemorrhage; D012453:Saimiri