title: Intraabdominal schwannomas: a single institution experience.
abstract: BACKGROUND
  Intraabdominal schwannomas are rare, benign tumors. This study presents a single institution experience with 12 such tumors.
  
  
  METHODS
  Between 1991 to 2006, 12 patients with a pathologically proven intraabdominal schwannoma were identified from a series of 216 mesenchymal tumors and were reviewed retrospectively.
  
  
  RESULTS
  There were nine females and three male patients with a median age of 58 years (range 35-88 years). Eleven patients were symptomatic, and the tumors were located in the stomach (n = 8), jejunum, colon, rectum, and lesser sac. Multiple preoperative investigations including endoscopies with biopsies and computed tomography (CT) scans were performed, but none yielded a correct definitive preoperative diagnosis. The median tumor size was 52 mm (range 18-95 mm). Pathological examination demonstrated the 11 gastrointestinal tract (GIT) schwannomas to be solid homogenous tumors, which were highly cellular and were composed of spindle cells with positive staining for S100 protein. The pathological appearance of the lesser sac schwannoma was distinct as it demonstrated cystic degeneration with hemorrhage and Antoni A and B areas on microscopy typical of soft tissue schwannomas. All 12 patients were disease-free at a median follow-up of 22 months (range 1-120 months).
  
  
  CONCLUSIONS
  Intraabdominal schwannomas are rare tumors, which are most frequently located within the GIT. GIT schwannomas are difficult if not impossible to diagnose preoperatively as endoscopic and radiologic findings are nonspecific. The treatment of choice is complete surgical excision because of diagnostic uncertainty, and the long-term outcome is excellent as these lesions are uniformly benign.
authors: Department of General Surgery, Singapore General Hospital, Outram Road, Singapore, Singapore 169608. bsgkp@hotmail.com
authors: Brian K P
authors: BK
authors: Goh
authors: Pierce K H
authors: PK
authors: Chow
authors: Sittampalam
authors: S
authors: Kesavan
authors: Wai-Ming
authors: WM
authors: Yap
authors: Hock-Soo
authors: HS
authors: Ong
authors: In-Chin
authors: IC
authors: Song
authors: Kong-Weng
authors: KW
authors: Eu
authors: Wai-Keong
authors: WK
authors: Wong
mesh_terms: D000008:Abdominal Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies