title: Clinical, radiological, and pathological features of 26 intracranial and intraspinal malignant peripheral nerve sheath tumors.
abstract: OBJECTIVE
  Intracranial and intraspinal malignant peripheral nerve sheath tumors (MPNSTs) are rarely reported because of their extremely low incidence. Knowledge about these tumors is poor. In this study the authors aimed to analyze the incidence and clinical, radiological, and pathological features of intracranial and intraspinal MPNSTs.
  
  
  METHODS
  Among 4000 cases of intracranial and intraspinal PNSTs surgically treated between 2004 and 2011 at Beijing Tiantan Hospital, cases of MPNST were chosen for analysis and were retrospectively reviewed. To determine which parameters were associated with longer progression-free survival (PFS) and overall survival (OS), statistical analysis was performed.
  
  
  RESULTS
  Malignant PNSTs accounted for 0.65% of the entire series of intracranial and intraspinal PNSTs. Twenty-four (92.3%) of these 26 MPNSTs were primary. Radiologically, 26.9% (7 of 26) of the MPNSTs were misdiagnosed as nonschwannoma diseases. Twenty-one patients were followed up for 1.5 to 102 months after surgery. Twelve patients experienced tumor recurrence, and median PFS was 15.0 months. The 2- and 3-year PFS rates were 47.7% and 32.7%, respectively. Five patients died of tumor recurrence, and median OS was not available. The 2- and 3-year OS rates were 74.7% and 64.0%, respectively. Univariate analysis revealed that female sex, total tumor removal, and primary MPNSTs were significantly associated with a better prognosis. Multivariate analysis revealed that only total removal was an independent prognostic factor for both PFS and OS.
  
  
  CONCLUSIONS
  Malignant PNST within the skull or spinal canal is a rare neoplasm and is seldom caused by benign schwannomas. Radiologically, intracranial or intraspinal MPNST should be differentiated from meningioma, chordoma, fibrous dysplasia of bone, and ear cancer. Total resection whenever possible is necessary for the prolonged survival of patients, especially males.
authors.affiliation: Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, People’s Republic of China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Ren
authors.forename: Junmei
authors.initials: J
authors.lastname: Wang
authors.forename: Mengqing
authors.initials: M
authors.lastname: Hu
authors.forename: Haihui
authors.initials: H
authors.lastname: Jiang
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Zhongli
authors.initials: Z
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology*; D002648:Child; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology*; D018317:Nerve Sheath Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology*; D011859:Radiography; D012189:Retrospective Studies; D012737:Sex Factors; D013120:Spinal Cord Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology*; D015996:Survival Rate; D016896:Treatment Outcome; D055815:Young Adult