十二指腸乳頭部癌のX線検査中に発見された十二指腸水平部微小Ⅱc型粘膜内癌の1例

Minute Type Ⅱc Early Duodenal Cancer of the Third Portion Discovered During the X-ray Examination of Early Cancer of Papilla of Vater, Report of a Case

要旨　患者は61歳，男性．近医での上部消化管内視鏡検査にて十二指腸乳頭部癌を発見され，当院上部消化管X線検査中，十二指腸水平部に陥凹性病変を指摘された．内視鏡検査で同部前壁に径約4mmのⅡc病変が確認され，生検結果は腺腫成分を伴う高分化型腺癌であった．乳頭部癌もあり，膵頭十二指腸切除が施行された．組織診断は術前生検と同様の粘膜内癌で，リンパ節転移は認められなかった．本例はわが国にて報告された陥凹型早期十二指腸癌15例目にあたり，腫瘍径が最小であった．本例の組織発生は腺腫の癌化と考えられ，過去14例の癌に腺腫成分を有するという記載がないことから，本例はごく初期の十二指腸癌の病理像を示す貴重な症例と考えられた．

　A 61-year-old man, who was diagnosed by a clinician, as having a cancer of the papilla of Vater was admitted to our hospital for precise examination of it. During barium-contrast x-ray examination of the upper gastrointestine, a minute depressed lesion of the third portion of the duodenum other than an enlargement of the papilla of Vater was incidentally discovered. Endoscopically, the lesion was confirmed to be type Ⅱc early duodenal cancer, and so some biopsy specimens were taken from it. They indicated well-differentiated adenocarcinoma accompanied by adenomatous component. We carried out pancreatoduodenectomy, because the cancer of the Papilla of Vater existed simultaneously with this lesion. Histological diagnosis of the resected specimen was the same as that made from the biopsy specimen, and the cancer depth of the depressed lesion was within the mucosal layer. No accompanying lymph node metastasis was detected. Our case was the 15th case of depressed-type early duodenal cancers reported in Japan and one of the smallest among them, being only 4 mm in diameter. We think that this case is highly interesting for indicating a very early state of depressed-type duodenal cancer.