title: Small gastrointestinal stromal tumours with focal areas of low attenuation on CT: pathological correlation.
abstract: OBJECTIVE
  To describe the pathology of focal areas of low attenuation in small gastrointestinal stromal tumours on contrast-enhanced computed tomography (CT), and to investigate the association of these areas as predictors of malignant potential.
  
  
  METHODS
  Contrast-enhanced helical CT images were obtained of 39 small (up to 5 cm) gastrointestinal stromal tumours. Focal areas of low attenuation were retrospectively evaluated and correlated with histopathological findings. The relation between the mitotic rate of and the presence of focal areas of low attenuation in the tumours was analyzed using Fisher's exact test.
  
  
  RESULTS
  Of the 39 small gastrointestinal stromal tumours, 15 contained focal areas of low attenuation on CT. These were found to be due to solid tumour (n=5), haemorrhage (n=3), haemorrhage with necrosis (n=2), cystic degeneration (n=2), fluid in ulcer (n=2), and fibrous septum (n=1); they were not found to be associated with a high mitotic rate (p=0.45).
  
  
  CONCLUSIONS
  Focal areas of low attenuation on CT in small gastrointestinal stromal tumours represent varying pathological conditions and do not predict malignant potential.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: H C
authors.initials: HC
authors.lastname: Kim
authors.forename: J M
authors.initials: JM
authors.lastname: Lee
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: S H
authors.initials: SH
authors.lastname: Park
authors.forename: J W
authors.initials: JW
authors.lastname: Lee
authors.forename: M
authors.initials: M
authors.lastname: Lee
authors.forename: J K
authors.initials: JK
authors.lastname: Han
authors.forename: B I
authors.initials: BI
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed