術前Ⅱa＋depression型腺腫と診断されたⅡa＋Ⅱc型大腸sm癌の1例

Type Ⅱa＋Ⅱc Submucosal Cancer of the Colon which was Falsely Regarded as Ⅱa＋Depression, Report of a Case

要旨　患者は54歳，男性．約7年前他院にて横行結腸部分切除を受け，経過観察目的で当科にて大腸内視鏡検査を施行された．上行結腸に中央に陥凹を伴う扁平隆起性病変が発見された．Ⅱa＋depression型の大腸腺腫と診断され内視鏡的粘膜切除が施行された．病理組織学的には4mmのⅡa＋Ⅱc型の分化型腺癌で粘膜下層に浸潤していた（sm₁）．

　A 54-year-old man had undergone endoscopic resection for a type Isp early cancer in the transverse colon seven years before. Colonoscopic examination during follow-up surveillance revealed a reddish flat elevation with an irregular depression in the ascending colon. The lesion was diagnosed as type Ⅱa＋depression adenoma, and endoscopic resection in the ascending colon was performed. Histologically, the lesion proved to be a well differentiated adenocarcinoma, type Ⅱa＋Ⅱc in shape, 4 mm in size, partially invading the submucosa (sm₁)．