title: Diagnosis of the invasion depth of gastric cancer using MDCT with virtual gastroscopy: comparison with staging with endoscopic ultrasound.
abstract: OBJECTIVE
  The objectives of this study were to retrospectively evaluate the lesion detection rate of gastric cancer using only virtual gastroscopy generated from MDCT images and the accuracy of invasion depth diagnosis (T staging) using virtual gastroscopy together with contrast-enhanced MDCT with multiplanar reconstruction (MPR) images (virtual gastroscopy with MPR), and to compare the diagnostic performance between virtual gastroscopy with MPR images and endoscopic ultrasound.
  
  
  METHODS
  The subjects consisted of 175 patients with a total of 186 endoscopically proven gastric cancer lesions. All patients underwent dynamic MDCT (arterial and venous phase) for preoperative staging and underwent surgery or endoscopic treatment. In 129 patients (135 lesions) who were also examined using endoscopic ultrasound, the T staging accuracy was also compared between the two modalities. Two endoscopists independently evaluated the lesion detection rate on virtual gastroscopy images alone and determined the T stage on virtual gastroscopy with MPR images. The T staging included the ability to differentiate T1a from T1b lesions.
  
  
  RESULTS
  The overall lesion detection rate was 67.7% (126/186). The detection rates of T1a, T1b, and T2 or deeper were 37.8% (28/74), 75.0% (39/52), and 98.3% (59/60), respectively, showing statistically significant differences (p < 0.001). The T staging accuracies were 82.2% (111/135) using virtual gastroscopy with MPR images and 83.7% (113/135) using endoscopic ultrasound, showing no statistically significant difference (p = 0.850). The main causes of over- and understaging were an ulcer or ulcer scar and poorly differentiated adenocarcinomas, non-solid type, respectively.
  
  
  CONCLUSIONS
  Virtual gastroscopy with MPR imaging is a useful modality in the T staging of gastric cancer.
authors.affiliation: Department of Gastroenterology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Furukawa
authors.forename: Ryoji
authors.initials: R
authors.lastname: Miyahara
authors.forename: Akihiro
authors.initials: A
authors.lastname: Itoh
authors.forename: Naoki
authors.initials: N
authors.lastname: Ohmiya
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Hirooka
authors.forename: Kensaku
authors.initials: K
authors.lastname: Mori
authors.forename: Hidemi
authors.initials: H
authors.lastname: Goto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003287:Contrast Media; D019160:Endosonography / Q000379:methods*; D005260:Female; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D007472:Iohexol; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; D007479:Iopamidol