食道胃接合部早期癌の内視鏡診断ならびにその特徴

Endoscopic Diagnosis for Early Cancer in the Esophagogastric Junctional Region

要旨　食道胃接合部癌は接合部上下2cmの間に病変の中心を置く癌である．当科での早期癌は，接合部癌90例中15例にすぎず早期診断が困難と思われる．早期癌の肉眼分類では，陥凹性病変が多く，組織型では，分化型腺癌が多く認められた．内視鏡診断では，近接観察や染色法を併用した診断が早期発見には重要であり，合わせて超音波内視鏡による深達度診断を行うことにより適切な治療法の選択が可能となる．接合部は空間的に狭いため病巣描出には先端にバルーンを装着した細径プローブが必要となるが，バルーンによる病巣の圧迫はsm層を伸展させ深達度を深く読む傾向があった．また先端に透明フードを付ける生検法は狙撃生検に有用である．

　Esophagocardiac junctional cancer is cancer where the center of the lesion is located within 2 cm above and below the esophagogastric junction. Cases of early cancers of this type are few, and we have encountered only 15 early cases in 90 cases, which means that diagnosis in the early phase is difficult. Macroscopic findings show that many of such cancers are depressed lesions and, hislotogically, are diagnosed as differentiated carcinoma. For endoscopic examination, close observation and dyeing methods are important for detecting the early cases. The diagnosis of the invasion depth by EUS is also useful to indicate the appropriate treatment. Because of the narrow space of the junctional area, it is necessary to use a balloon mounted on the tip of the thin EUS probe for getting a clear image of the lesion. However, due to the oppression of the sm layer, using a balloon can lead to over estimation of the invasion depth. Using a transparent hood is also useful for precise biopsy.