全大腸にわたるびまん性の過形成性結節を母地として発生した多発大腸癌と腺腫が合併した1例

Multiple Adenocarcinomas and Adenomas of the Colon Developed from the Mucosa with Numerous Hyperplastic Nodules, Report of a Case

要旨　患者は21歳，男性．1991年6月，血便を主訴として来院．直腸にBorrmann2型の進行癌を認め，低位前方切除を施行．術後の切除標本の検索で微小癌および背景粘膜の異常を認めた．残存大腸の内視鏡検査にて，多数の過形成性結節や腺腫が認められ，切除標本と同様の所見で，生検にてGroup 5と診断される病変が認められたため，1992年5月，残存結腸切除術が施行された．大腸全体にびまん性に過形成性結節が1,563個認められ，直腸に1個の進行癌と1個の微小癌，下行結腸に1個の腺癌と1個の過形成性結節内癌を認め，そのほか，異型上皮6個，腺腫26個，過形成性結節内腺腫2個，化生性（過形成性）ポリープ16個を認め，極めてまれな症例と思われた．

　A 21-year-old man was admitted to our hospital with a complaint of anal bleeding on defecation. Sigmoidoscopy revealed a Borrmann type 2 advanced carcinoma in the rectum. Low anterior resection was performed. Resected specimen showed a Borrmann type 2 advanced carcinoma and numerous nodules less than 5 mm in size. Postoperative colonofiberscopy also revealed numerous nodules throughout the remnant colon and rectum. One of biopsy specimens obtained from these nodules showed adenocarcinoma. Total colectomy and ileoanal anastomosis were performed. Histological examination of the resected specimens showed 1,563 hyperplastic nodules, 16 metaplastic (hyperplastic) polyps, 28 adenomas, two of which had developed in hyperplastic nodules, 6 dysplasias, one advanced carcinoma and three mucosal carcinomas, one of which had developed in a hyperplastic nodule. Therefore, it is suggested that mucosa with diffuse hyperplastic nodules could develop adenoma and carcinoma in this case.