title: Subarachnoid hemorrhage caused by an undifferentiated sarcoma of the sellar region.
abstract: BACKGROUND
  It is rare for patients with pituitary apoplexy to exhibit concomitant subarachnoid hemorrhage (SAH). Only a handful of patients with pituitary apoplexy have developed such hemorrhagic complications, and histopathological examination revealed pituitary adenoma as the cause of SAH.
  
  
  METHODS
  A previously healthy 35-year-old woman was brought to our institution after complaining of severe headache and left monocular blindness. Brain computed tomography showed a diffuse SAH with a central low density. Subsequently, the brain magnetic resonance imaging revealed an intrasellar mass with heterogeneous contrast enhancement. The patient was presumptively diagnosed with SAH secondary to hemorrhagic pituitary adenoma and underwent transcranial surgery to remove both the tumor and subarachnoid clot. A histological evaluation of the surgical specimen revealed malignant cells with strong predilection for vascular invasion. Following immunohistochemical evaluation, the tumor was negative for the majority of tumor markers and was positive only for vimentin and p53; thus, a diagnosis of undifferentiated sarcoma was established.
  
  
  CONCLUSIONS
  This case was informative in the respect that tumors other than pituitary adenoma should be included in the differential diagnosis of patients with pituitary apoplexy.
authors: Department of Neurosurgery, Fujita Health University Hospital, Toyoake, Japan.
authors: Tsukasa
authors: T
authors: Ganaha
authors: Department of Neurosurgery, Fujita Health University Hospital, Toyoake, Japan.
authors: Joji
authors: J
authors: Inamasu
authors: Department of Neurosurgery, Fujita Health University Hospital, Toyoake, Japan.
authors: Motoki
authors: M
authors: Oheda
authors: Department of Neurosurgery, Fujita Health University Hospital, Toyoake, Japan.
authors: Mitsuhiro
authors: M
authors: Hasegawa
authors: Department of Neurosurgery, Fujita Health University Hospital, Toyoake, Japan.
authors: Yuichi
authors: Y
authors: Hirose
authors: Department of Diagnostic Pathology, Fujita Health University Hospital, Toyoake, Japan.
authors: Masato
authors: M
authors: Abe
keywords: Pituitary apoplexy; sella turcica; subarachnoid hemorrhage; undifferentiated sarcoma