潰瘍性大腸炎に合併した結節集簇様病変の1例

Nodule-aggregating Tubulovillous Adenoma of the Rectum Complicating Ulcerative Colitis, Report of a Case

要旨　患者は31歳，男性．1982年10月から血性下痢が出現し，翌年全結腸型潰瘍性大腸炎と診断された．その後，salazosulfapyridine投与のみで明らかな再燃はなかったが，発症後約8年目の大腸X線・内視鏡検査で，中部直腸に約半周性の軽度発赤した平坦な結節集簇様病変を認めた．手術で，大きさ35×30mmの平坦な隆起性病変で，大小の結節が集簇していた．病理組織学的には中等度異型を伴う管状絨毛腺腫で，癌の部分は認めなかった．病変周囲粘膜は萎縮が著明で，病理組織学的にも寛解期の潰瘍性大腸炎に合致し，dysplasiaは認めなかった．なお，遡及的検討で，3年前のX線検査では，同部位に22×22mmの不整な顆粒と小結節が集簇する病変を認めた．

　A 34-year-old man with a history of extensive ulcerative colitis (UC) involving the entire colon had been followed up over eight years regularly by radiological examination with an interval of about three years. His clinical course had been fair without any major symptoms with a medication of salazosulfapyridine (SASP) 400 mg/day until Sep. 1990 (eight years after the onset of UC), when a nodule-aggregating flat lesion in the rectum was pointed out by radiological examination. Colonoscopic examination detected a slightly reddish flat elevated lesion with a conglomerated nodular surface and an operation (low anterior resection) was performed. Macroscopic findings showed a noduleaggregating flat lesion, 35×30 mm in size, which was surrounded by atrophic mucosa indicating chronic UC. Pathological diagnosis of the flat elevated lesion was a tubulovillous adenoma surrounded by atrophic mucosa compatible with chronic UC. Radiological retrospective study revealed a flat elevated lesion with granular and/or nodular surface, measuring 22×22 mm, in Aug. 1987. However, in Sep. 1984, no lesion could be pointed out except for the finding of chronic UC. Patients with UC must be followed up at regular intervals by barium enema and/or colonoscopy.