The Magnified Endoscopic Finding Of An Irregular Microvascular Pattern Is A Very Useful Marker For Differentiating Between Gastritis And Gastric Cancer: A Prospective Study

Aim: It is often difficult using standard endoscopy to make an endoscopic diagnosis of the flat type of early gastric cancer that mimics gastritis. We previously reported the magnified endoscopic findings of the microvascular architecture of differentiated type of flat reddened gastric carcinoma (Gastrointest Endosc 2002; 56: 279-84). The aim of this study was to investigate the diagnostic accuracy of these magnified endoscopic findings for differentiating between reddened mucosa due to gastritis and flat reddened gastric cancer, prospectively. Methods: 390 cases were included in this study. The patients received upper gastrointestinal endoscopic examination for the screening of gastric cancer by zoom endoscope GIF-Q240Z (Olympus, Tokyo, Japan). If a flat reddened lesion was detected by non-magnified observation, the lesion was subsequently magnified by a zooming attachment. Immediately after the examination, the following findings which have been reported to be characteristic of carcinoma were recorded. (1) Presence of a demarcation line between the reddened lesion and the surrounding mucosa, (2) Disappearance of a regular subepithelial capillary network pattern of the same shape as that within the surrounding mucosa, and (3) Proliferation of microvessels irregular in both shape and distribution (irregular microvascular pattern). According to the pathological diagnosis, the flat reddened lesions were divided into two groups, i.e. gastritis and carcinoma groups. The incidence and 95% confidence intervals (CI) of these findings were calculated for each of the respective groups. Results: 161 flat reddened lesions from 161 cases were detected. Pathologically, 123 lesions showed only gastritis, while 38 lesions were diagnosed as differentiated carcinoma. The incidence (95% CI) of the magnified endoscopic findings in gastritis vs. carcinoma was (1) 22.8% (15.4-30.2%) vs. 97.4% (92.3-100%), (2) 19.5% (12.5-26.5%) vs. 100% and (3) 0.8% (0-2.4%) vs. 97.4% (92.3-100%), respectively. As for the differential diagnosis of carcinoma from gastritis, the sensitivity and the specificity of the irregular microvascular pattern were 97.4 and 99.2, respectively. Conclusion: An irregular microvascular pattern visible by magnified endoscopy can be a very useful marker for differentiating between gastritis and carcinoma.