直腸上部Ⅱc型早期癌の1例

Type Ⅱc Early Cancer in the Upper Rectum, Report of a Case

要旨　患者は55歳，男性．主訴は右上腹部痛．検査法は当院独自の内視鏡-X線同日併用法によった．内視鏡は挿入時より撮影を行い，上部直腸に一部発赤を有する孤立性類円形の小陥凹病変を確認した．2個の生検にて高分化腺癌であった．注腸造影でも上部直腸に10mm以下の不整円形病変が認められた．切除標本の肉眼像では，11×5mm大のⅡc型であった．病理組織所見ではⅡc内はすべて構造異型の乏しい高分化腺癌であった．本症例が陥凹型であって，深達度がsm，直径11×5mm大という点から，また検索した範囲内ではadenomaの要素はなく，de novo癌も十分考慮される．また内視鏡的観察で明瞭な陥凹像，大きさ，深達度がほぼ推測しえた症例としては，本邦初と考えられる．手術は国立がんセンターで行われ，下行結腸に2個の腺腫性ポリープと横行結腸にBorrmann 2型の癌の合併病変を認めた．

　The patient, a 55-year-old man, complained of a right epigastric pain. He underwent the combination study of endoscopy and radiography, a unique mode of study developed in our Hospital. Upon insertion of a fiberscope, an isolated, small depressed lesion was found in the upper rectum. This was aimost round and partially reddened. Two biopsy specimens suggested a diagnosis of well differentiated adenocarcinoma. Barium enema detected this lesion in the upper rectum, the one less than 10 mm in diameter and of irregularly round configuration.

　Macroscopy of the resected specimen showed type IIc cancer measuring 11×5 mm in diameter. Histologically, it was a well differentiated adenocarcinoma with almost no structural atypia within the lesion. Thus it is likely that this lesion with a depth of invasion grade sm was a de novo cancer. This was the first case in Japan to our knowledge that endoscopy gave a clear image of depressed lesion and allowed us to estimate the size and depth of invasion. The patient was operated at the National Cancer Center Hospital and found to have two adenomatous polyps in the descending colon accompanied by a Borrmann type 2 cancer in the transverse colon.