Chiao Yun Chen MD, Presenter: Nothing to Disclose

Gin-Chung Liu MD, Abstract Co-Author: Nothing to Disclose

Twei-Shiun Jaw MD, Abstract Co-Author: Nothing to Disclose

Yu-Ting Kuo MD, Abstract Co-Author: Nothing to Disclose

Jui-Sheng Hsu MD, PhD, Abstract Co-Author: Nothing to Disclose

Chien-Hung Lee Lee, Abstract Co-Author: Nothing to Disclose

To compare the performance of CT virtual gastroscopy(VG) and gastroendoscopy(ENDO) in the differentiation of malignant and benign gastric ulcers.

A total of 78 consecutive patients with gastric ulcers diagnosed by ENDO were prospectively performed 16-row MDCT with VG within 4 days. There were proved 31 benign and 47 malignant ulcers(adenocarcinoma, 9 T1, 18 T2 and 20 T3). The ENDO was performed by an endoscopist. All patients were given 6g gas-producing crystals before unenhanced CT scan for VG .VG images were evaluated by two experienced gastrointestinal radiologists who were blind to ENDO findings independently. We evaluated each ulcer by the shape, base, margin of the ulcers and peri-ulcer fold changes. The criteria of malignant gastric ulcers are: geographic shape, uneven base, irregular margin and fold changes with bulbous enlargement, fusion or abrupt termination. In contrast, benign gastric ulcers have round or oval shape, even base, regular margin and smooth tapering of the radiating gastric folds. For comparing VG and Endo results, the McNemar test was used, and a P value of less than .05 was defined statistical significance.

The sensitivity and specificity of VG in detecting malignant ulcers were 84%,83% in ulcer shape; 79%,57% in base; 86%,86% in margin criteria; and 90%,77% in fold changes. The corresponding sensitivity and specificity of ENDO were 84%, 86% in shape; 82%,79% in base; 80%,91% in margin criteria; and 96%,68% in fold changes. No significant difference exists between these two modalities in differentiating malignant from benign ulcers by ulcer shape(P=.76), margin(P=.18) or peri-ulcer fold changes(P=1.00). However, ENDO was significantly better than VG(P=.002) in differentiation between malignant and benign ulcer using ulcer base criteria.

Except in determining ulcer base, as compared to ENDO, VG using other criteria mentioned above provides comparative results in differential diagnosis between malignant and benign gastric ulcers.

As compared with conventional ENDO, MDCT with VG provides comparative diagnostic accuracy; and hence can be as a good non-invasive alternative imaging modality to differentiate malignant and benign gastric ulcers.

Chen, C, Liu, G, Jaw, T, Kuo, Y, Hsu, J, Lee, C, Differentiation of Malignant and Benign Gastric Ulcers: Comparison between CT Virtual Gastrocsopy and Gastroendoscopy.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4436579.html