title: MDCT and clinicopathological features of small bowel gastrointestinal stromal tumours in 102 patients: a single institute experience.
abstract: OBJECTIVE
  Small bowel (SB) is the second most common site of gastrointestinal stromal tumours (GISTs). We evaluated clinical presentation, pathology, imaging features and metastatic pattern of SB GIST.
  
  
  METHODS
  Imaging and clinicopathological data of 102 patients with jejunal/ileal GIST treated at Dana-Farber Cancer Institute and Brigham and Women's Hospital (Boston, MA) between 2002 and 2013 were evaluated. Imaging of treatment-naive primary tumour (41 patients) and follow-up imaging in all patients was reviewed.
  
  
  RESULTS
  90/102 patients were symptomatic at presentation, abdominal pain and lower gastrointestinal blood loss being the most common symptoms. On pathology, 21 GISTs were low risk, 17 were intermediate and 64 were high risk. The mean tumour size was 8.5 cm. On baseline CT (n = 41), tumours were predominantly well circumscribed, exophytic and smooth/mildly lobulated in contour. Of 41 tumours, 16 (39%) were homogeneous, whereas 25 (61%) were heterogeneous. Of the 41 tumours, cystic/necrotic areas (Hounsfield units < 20) were seen in 16 (39%) and calcifications in 9 (22%). CT demonstrated complications in 13/41 (32%) patients in the form of tumour-bowel fistula (TBF) (7/41), bowel obstruction (4/41) and intraperitoneal rupture (2/41). Amongst 102 total patients, metastases developed in 51 (50%) patients (27 at presentation), predominantly involving peritoneum (40/102) and liver (32/102). 7/8 (87%) patients having intraperitoneal rupture at presentation developed metastases. Metastases elsewhere were always associated with hepatic/peritoneal metastases. At last follow-up, 28 patients were deceased (median survival, 65 months).
  
  
  CONCLUSIONS
  SB GISTs were predominantly large, well-circumscribed, exophytic tumours with or without cystic/necrotic areas. Complications such as TBF, bowel obstruction and intraperitoneal perforation were visualized at presentation, with patients with perforation demonstrating a high risk of metastatic disease. Exophytic eccentric bowel wall involvement and lack of associated adenopathy are useful indicators to help differentiate GISTs from other SB neoplasms.
  
  
  CONCLUSIONS
  SB GISTs are predominantly large, well-circumscribed, exophytic tumours, and may present with complications. They often are symptomatic at presentation, are high risk on pathology and metastasize to the peritoneum more commonly than the liver.
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: A D
authors.initials: AD
authors.lastname: Baheti
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: A B
authors.initials: AB
authors.lastname: Shinagare
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: A C
authors.initials: AC
authors.lastname: O'Neill
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Krajewski
authors.affiliation: 3 Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Hornick
authors.affiliation: 4 Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: S
authors.initials: S
authors.lastname: George
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: N H
authors.initials: NH
authors.lastname: Ramaiya
authors.affiliation: 1 Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.|2 Department of Imaging, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Tirumani
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000556:secondary; D006801:Humans; D007421:Intestine, Small / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor