大腸lateral spreading tumor―non-granular typeの2例

Non-granulated Type of Lateral Spreading Tumor of the Colon, Report of Two Cases

要旨　大腸lateral spreading tumor－non-granular typeの2例を経験したので報告する．〔症例1〕は46歳，男性．主訴は便潜血陽性．注腸および大腸内視鏡検査で，横行結腸に扁平な側方発育型腫瘍を認め，腸切除術を施行した．病理組織学的には径35×33mm，深達度mの高分化腺癌であった．〔症例2〕は61歳，男性．虫垂炎術後の経過観察をしていた．注腸および大腸内視鏡検査で，横行結腸に変形を伴い陥凹部を有する側方発育型腫瘍を認め，腸切除術を施行した．病理組織学的には径30×21mm，陥凹部でsmに浸潤した高分化腺癌であった．2症例はともに顆粒を伴わない側方発育型腫瘍であり，いずれも腫瘍辺縁の花弁状はみ出し所見と腫瘍表面に溝を伴っている点で興味深かった．

　We present two cases of colonic lateral spreading tumors. The first case is a 46-year-old male who visited our hospital because of positive fecal occult blood. A non-granulated wide-spread flat elevated lesion of the transverse colon was detected by barium enema and colonoscopic examination. Partial colectomy was performed. On the resected specimen, the lesion, measuring 35×33 mm in size, was revealed to be well differentiated adenocarcinoma which was histologically restricted to the mucosa. The second case was a 61-year-old male who was followed up after an appendectomy. A non-granulated widespread flat elevated lesion which had a depression with a deformity of the colonic wall was detected at the transverse colon. Partial colectomy was performed. The resected specimen showed the lesion which was 30×21 mm in size, and the histological examination showed a well differentiated adenocarcinoma with submucosal invasion at the depressed area and tubular adenoma at the surrounding flat area. Both cases of non-granulated type of lateral spreading tumors endoscopically showed a butterfly-shaped figure and ditch on the surface of the lesion.