Endoscopic ultrasonography ; Stomach Cancer ; Staging
Abstract
Endoscopic ultrasonography(EUS) has been used in assessing the depth of cancer invasion of the stomach. To find out the factors affecting the diagnostic accuracy of EUS in determin- ing the depth of cancer invasion, we analysed 116 cases of gastric cancer performed EUS. One hundred and sixteen cases who were operated for gastric cancer were evaluated by EUS prior to operation. EUS was performed with a 7.5 MHz Olympus EUS. The results were compared with the depth of cancer invasion of the resected specimen and analysed the pathologic findings in mis-staging cases. The degree of vertieal invasion of gastric cancer was classified into 4 stages'. Mucosa, submucosa, muscularis propria, and serosa. Overall accuracy of EUS in determining the depth of cancer invasion was 67.2%(78 of 116 cases). The diagnostic accura- cy in the depth of tumor invasion showed no difference in relation to location of tumor, histo- logic type, and degree of differentiation. In contrast, the diagnostic accuracy was higher in small size(less than 4cm) of tumor than large size(more than 4cm) of tumor, and in non-ul- cerative type than ulcerative type in early gastric cancer. In advanced gastric cancer, the di- agnostic accuracy was higher in large size(more than 6cm) of turnor than small size(less than 2cm) of tumor. The main pathologic findings of overstaging were fibrosis coexisting ulcer and compression of adjacent layer by the tumor, and understaging was microinvasion of cancer.