肉眼像からみた食道表在癌の深達度の読み方

Macroscopic Evaluation of the Depth of Invasion in Superficial Esophageal Carcinoma

要旨　食道表在癌136例（ep癌29例，mm癌26例，sm癌81例）を用いて，肉眼像から見た深達度診断について検討した．広く受け入れられる判定基準を得るためには，まず食道新鮮標本の取り扱いが重要で，120～150％程度に伸展して写真撮影および固定を行う必要がある．このようにして得られた標本を用いての検討では以下に示す結果であった．隆起性病変では隆起の高さが最も重要な指標となり，2mm以上はsm，1mm以下はep～mmの確率が高い．隆起の立ち上がり方，色調も深達度診断に有用で，隆起の高さにそれらを加味することにより診断の精度が向上する．陥凹性病変では，陥凹の深さが最も重要である．深さ0.5mm未満はep～mm癌，0.5mmを越えればsm癌の可能性が高く，lmmを越えればsm以上に浸潤している．陥凹底の穎粒状変化も重要で，色調差も参考になる．混合型は隆起，陥凹の各要素ごとの判定基準を適用すれば，概ね妥当な深達度診断が可能である．

　To evaluate the depth of invasion of cancer based on macroscopic morphology, we reviewed 136 cases of superficial esophageal carcinoma regarding macroscopic and microscopic findings. The cases consist of 29 cases of intraepithelial carcinoma (ep), 26 cases of mucosal carcinoma (mm) and 81cases of carcinoma with submacosal invasio (sm). In order to establish general criteria, it was necessary to stretch the winkles of the mucosa of fresh resected materials and to magnify 120-150%. The review of macroscopic findings of superficial carcinomas under such conditions yielded the following results. In protruded lesions, the height was the most important factor in estimating the depth of invasion. Lesions taller than 2 mm suggested sm carcinoma. On the other hand, lesions of ep or mm carcinoma did not usually exceed 1 mm in height. Shape and color of lesions were important diagnostic clues, too. In depressed lesions, the most useful index was the depth of depression. In ep or mm carcinoma, depression was shallow with the depth less than 0.5 mm in most cases. When the invasion of carcinoma involved submucosal layer, the depth usually exceeded 0.5 mm. Findings of the bottom of depression was also useful diagnosticclue. Combination of these criteria for elevated and depressed lesions provided valid clues in differentiating ep, mm and sm carcinomas.