INTRODUCTIONIn this session, the impact of a new magnification endoscopy in the diagnosis of esophageal and gastric lesions is discussed.Development of a new magnification endoscopy So far, many studies utilizing magnification endoscopy have been reported, but some limitations have existed to the routine use of it. Older magnifying endoscopes had a larger diameter, and were relatively difficult for insertion through the pharynx, and therefore magnifying endoscopy actually became an additional study to the routine endoscopic ex-amination. A new magnifying endoscope (Q240Z, Olympus Optical Co., Tokyo, Japan) keeps the same size in scope diameter approximately to a screening endoscope (Q240,Olympus). It also mounts a high resolution CCD tip same to a routine endoscope and it also has a 80¥magnifying power. In other words, an endoscopist can use a new magni-fying endoscope as a routine screening endoscopy if a magni-fying observation of the lesion is not necessary.Magnification endoscopic findings in the esophageal lesion In the esophagus, magnification endoscopy facilitates well, both to the diagnosis of the negatively stained lesion with iodine and to the evaluation of infiltration depth of squamous cell carcinoma. In squamous epithelium magnifi-cation, endoscopy reveals changes of fine vascular network pattern on the mucosa and submucosa. Regularly arranged intrapapillary capillary loops (IPCL) are normally observed by utilizing magnification endoscopy (Fig.1). IPCL shows characteristic changes in carcinoma in situ . Those include weaving, dilatation, irregular caliber and a different shape in each IPCL. According to the grade of IPCL changes, target epithelium can be diagnosed from normal mucosa (T ype I) to carcinoma (Type V) (Fig.2). By the evaluation of IPCL changes, infiltration depth of the cancerous lesion can also be assessed. In the m 1lesion, characteristic changes in are observed (Fig.2). In the m 2lesion the elongation of affected IPCL is observed, and in the m 3lesion destruction of IPCL becomes much more obvious. In the sm cancer, almost total IPCL has been destructed and a novel tumor vessel often appears (Fig.3). In the esophagus, the usefulness of magnify-ing endoscopy is gradually but steadily recognized.Digestive Endoscopy (2001) 13(Suppl.), S40–S41SESSION 2: MODERATOR’S COMMENTMAGNIFICATION ENDOSCOPY IN THE ESOPHAGUS AND STOMACHHaruhiro InoueShowa University, Northern Yokohama Hospital, Yokohama, JapanCorrespondence: Haruhiro Inoue, Assistant Professor Chief of Upper Gastrointestinal Endoscopy and Surgery, Showa University,Northern Yokohama Hospital, Chuo 35-1, Tsuzuki-ku, Yokohama 224-2503, Japan. Email: haru.inoue@med.showa-u.ac.jpFig.1. A schematic representation of the vascular network of esophageal mucosa. (a) Submucosal drainage vein; (b) arborescentvessel; (c) intrapapillary capilary loop.Fig.2.Classification of intrapapillary capillary loop (IPCL )pattern. Type I, positively stained with iodine; IPCL no different from normal pattern. Type II, positively stained with iodine;IPCL have one or two out of four characteristic changes, and elongation and/or dilatation is commonly seen. often. Type III, negatively stained with iodine; IPCL have no changes or minimal changes. Type IV , negatively stained with iodine; IPCL have three out of four characteristic changes described in Type V . Type V; negatively stained with iodine; IPCL have all four characteristic changes indicating carcinoma-in-situ: dilatation,torturous running, caliber changes and different shapes in each IPCL.Magnification endoscopy in the stomachYao and Oishi 1first presented a basic histologic aspect of magnifying endoscopy in the stomach, and then clarifiedMAGNIFICATION ENDOSCOPY IN THE ESOPHAGUS AND STOMACH S41a well-demarcated area with loss of superficial capillary network and disappearance of normal pits structure.Undifferentiated adenocarcinomaIn the mucosal lesion with no ulceration (por, sig), magnifica-tion endoscopy showed a reduced density of subepithelial capillary network depending on the thickness of the carci-noma cells in the lamina propria mucosa. Undifferentiated type cancer cells often invade the deeper layer with no destruction of the surface epithelium.Yagi 2presented his recent data regarding to Helicobacter pylori (HP) infection and magnifiction endoscopic findings.Magnification endoscopic findings in the gastric body are classified into Z-0 to Z-3. Z-0 means a regular arrangement of collecting venules, which corresponds well to the helicobacter negative mucosa with more than 90% accuracy. These findings are valuable advancements in the diagnosis of HP infection.In the stomach, magnifying findings are generally more complicated than those in the esophagus. The stomach displays many characteristic features. There are three different types of glands, gastritis, mucosal atrophy, HP infection, intestinal metaplasia, benign ulceration, ulcer scar, differentiated or undifferentiated type adenocarcinoma, and others. All those themes will be clarified in the near future.REFERENCES1.Yao K, Oishi T. Microgastroscopic findings of mucosal microvascular architecture as visualized by magnifying endo-scopy. Dig. Endosc . 2001; 13 (Suppl.): S27–33.2.Yagi K. Endoscopic features and magnified views of the corpus in the Helicobacter pylori-negative stomach. Dig.Endosc . 2001; 13(Suppl.): S34–5.Fig.3.Changes in an intrapapillary capillary loop (IPCL ),according to the infiltration depth of T1 esophageal cancer. m 1,Characteristic IPCL changes to intraepithelial carcinoma (Type V changes) only affect the top of IPCL. m 2, Type V changes affect the middle part of the IPCL, and are observed as an elon-gation of the affected IPCL. m 3, Type V changes affect the total length of IPCL and the original shape of the IPCL has been destroyed. sm, Abnormal tumor vessels with large diameters have appeared.the following findings mainly based on the microvascular structures.Differentiated type adenocarcinomaDye enhancement is useful in the diagnosis of a differentiated adenocarcinoma. Differntiated adnocarcinoma often has。