Ⅱb型早期胃癌および微小胃癌の内視鏡所見

Endoscopic Findings of Ⅱb Type Early Gastric Cancer and Minute Cancer

　内視鏡器械の改良により，直視下生検が容易に行われるようになってきた．その結果，早期胃癌の発見率は上昇し，徐々にではあるが胃癌による死亡率は減少しつつある．しかしながら依然として切除胃癌の約半数は進行癌であるし，更に，切除胃の病理組織学的検討にて全く偶然に癌が発見されることもしばしばある．このことより，われわれが日常行っている内視鏡検査でいったいどのくらい癌を見逃しているだろうか．

　今回は，びらん，胃炎などとの鑑別が困難な比較的平坦な癌，すなわち微小癌，単独Ⅱb，随伴Ⅱbについて内視鏡所見を検討した．

　Studies were done on the 13 1esions of Ⅱb, 26 of minute cancer less than 5 mm, and 12 of accompanied Ⅱb, which we experienced at our department up to date.

　The classification of the Ⅱb lesions by size was as follows: seven out of 13 (53.8％) were minute cancer, and only four were of sizes over 1 cm. However, in view of the fact out of the four Ⅱb lesions of over 1 cm, two were ow (＋), the diagnosis of Ⅱb over a certain size seems important for clinical purpose. For this study, therefore, we classified the minute cancer as one group and relatively large Ⅱb including accompanied Ⅱb as another group.

　Of the 26 1eslons in 25 cases of minute cancer, these correctly diagnosed before operation were nine lesions in nine cases, seven of which were minute Ⅱc of Ul (－), which were endoscopically observed as“cloudy red”spots. These had to be further differentiated from benign erosion. Their differences from benign erosion were the irregularity and unevenness and somewhat cloudy red illuminations.

　With regards to accompanied Ⅱb, it is necessary to do biopsy carefully the oral side in the lesser curvature to avoid ow (＋),

　Of the relatively wide range of Ⅱb, the undifferentiated carcinoma located in the middle layer of lamina propria mucosae, not exposing itself on the surface, is extremely difficult to diagnose by endoscopy at present.

　Generally speaking, with regards to Ⅱb type early gastric cancer and minute cancer, the color finding has a great importance, and there remain many more problems yet to be solved or conditions to be improved in matters such as film, development, and pretreatment of the patient.