多発扁平隆起を合併した潰瘍性大腸炎の1例

Multiple Flat Elevations of the Colon Observed in Quiescent Ulcerative Colitis, Report of a Case

要旨　患者は67歳の男性．過去に明らかな粘血便の既往はない．1991年11月ごろから1日2～3行の下痢が出現し，近医を受診したところ大腸に異常を指摘され，当科に紹介され入院した．注腸X線検査，大腸内視鏡検査で全大腸に9個の扁平隆起性病変を認め，右側結腸を中心としたhaustraの消失と粘膜粗糙の所見，更に上行結腸の変形，回盲弁の破壊を思わせる所見が認められ，潰瘍性大腸炎または腸結核に合併した多発扁平隆起性病変と診断した．9個の扁平隆起のうち横行結腸と肝彎曲部の病変は，生検で癌が疑われたため右半結腸切除術を施行した．全割切除標本の検索で，背景粘膜は全大腸炎型の潰瘍性大腸炎であり，9個の扁平隆起のうち肝彎曲部の15mm大のⅡa＋Ⅰ型病変は腺腫内癌，横行結腸の25mm大のⅡaとEMRで切除したS状結腸の大きさ10mm大のⅡaは高度異型腺腫（borderline lesion），他の6病変は軽度異型腺腫と診断した．

　A 67-year-old man with multiple flat elevations of the colon is presented. He had never suffered from mucobloody stool in his life. Complaining of diarrhea 2～3 times a day, he took a colonoscopic examination in November, 1991. He was referred to our hospital for a close examination of the colon. Barium enema and colonoscopic findings revealed nine flat elevated lesions in the colon. The colon as background of these tumors showed disappearance of haustra coli and roughness of colonic mucosa chiefly in the right-sided colon, deformity of the ascending colon, and destruction of Bauhin's valve. Although these findings were compatible with chronic inflammatory changes, we were troubled to diagnose whether the disease was tuberculosis or ulcerative colitis. Of nine flat elevations two lesions on the transverse colon and on the hepatic flexure were suspected to be carcinomas. For this reason, the patient underwent right hemi-colectomy. Histopathological examination disclosed that the features of the colon in which these tumors were found were consistent with ulcerative colitis in the remission stage, and that type Ⅱa+Ⅰ lesion (15 mm in size) on the hepatic flexure was a cancer in an adenoma, type Ⅱa lesions on the transverse colon (25 mm in size) and on the sigmoid colon (10 mm in size; treated with endoscopic mucosal resection) were borderline, and the other six lesions were tubular adenomas with mild atypia.