IIc類似進行癌の形態を呈した原発性十二指腸印環細胞癌の1例

IIc-like Advanced Duodenal Signet-ring Cell Carcinoma, Report of a Case

要旨　患者は74歳，女性．便潜血陽性を指摘され二次検査目的で入院．低緊張性十二指腸造影にて，十二指腸第2部の乳頭口側・内側前壁寄りに，壁の伸展不良を伴う不整形の陥凹性病変を認めた．上部消化管内視鏡検査で病変の陥凹部分は，まだらな発赤を伴い小結節状の隆起を認め，生検にて印環細胞癌と診断された．以上より，原発性十二指腸癌の診断のもとに幽門輪温存膵頭十二指腸切除術を施行した．切除標本で腫瘍は十二指腸第2部の乳頭口側にあり，大きさ15×10mm，肉眼形態的には0 IIc Ul（＋）類似病変で，病理組織学的には印環細胞癌，深達度ssであった．文献上本例は，十二指腸印環細胞癌として本邦第7例目であったが，肉眼的にIIc類似進行印環細胞癌の形態を呈した症例は，他に報告をみなかった．

　A 74-year-old woman was hospitalized for further investigations after a positive fecal occult blood test. Hypotonic duodenography revealed an irregular concave lesion, accompanying poor wall extension, located orally on the internal side from the papilla of Vater in the second portion of the duodenum. Upper gastrointestinal endoscopy demonstrated variegated mucosal redness and small protruded nodules in the depressed part of the lesion. Histological examination of biopsy specimens showed signet-ring cell carcinoma. Under a diagnosis of primary duodenal carcinoma, we conducted a pylorus-preserving pancreaticoduodenectomy. In the resected specimen, the tumor was 15×10 mm in size, resembled IIc type with ulceration macroscopically, but, histologically, it was shown to have invaded to the subserosal layer. Six reports showed duodenal signet-ring cell carcinoma cases in Japan, but our case of, IIc-like advanced duodenal signet-ring cell carcinoma, is the first one to be documented in the medical literature in Japan.