Intraabdominal schwannomas: a single institution experience.
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.
Goh
Brian K P
BK
Department of General Surgery, Singapore General Hospital, Outram Road, Singapore, Singapore 169608. bsgkp@hotmail.com
Chow
Pierce K H
PK
Kesavan
Sittampalam
S
Yap
Wai-Ming
WM
Ong
Hock-Soo
HS
Song
In-Chin
IC
Eu
Kong-Weng
KW
Wong
Wai-Keong
WK
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