内腔閉塞を来した結節集簇様早期十二指腸癌の1例

Early Duodenal Cancer, Similar to Nodule-aggregating Lesions of the Colon and Occupying the Whole Lumen of the Duodenum, Report of a Case

要旨　患者は78歳，女性，主訴は悪心，嘔吐，体重減少．上部消化管X線検査で十二指腸第2部に全周性の陰影欠損を認め，血管造影では同部に微細な新生血管と腫瘍濃染を認めた．原発性十二指腸癌の診断の下に膵頭十二指腸切除術を施行した．腫瘍は9×6cm，十二指腸内腔に乳頭状に発育し，肉眼的には大腸の結節集簇様病変に類似していた．病理組織学的には大部分は低異型度から高異型度を示す不規則な腺管の増生を認める高分化腺癌で，また一部には腺腫との鑑別が困難な部位もあった．深達度は粘膜下層までで，いわゆる早期癌と考えられた．本邦での原発性早期十二指腸癌の報告は自験例を含め163例であり，なかでも自験例は最大径で，また内腔閉塞を来したまれな症例と考え，発癌に関しての若干の文献的考察を加え報告した．

　A 78-year-old woman was admitted to our hospital because of nausea and vomiting. Upper gastrointestinal series revealed incomplete stenosis of the second portion of the duodenum and dilatation of the bulbar lesion. The final diagnosis obtained by biopsy revealed well differentiated adenocarcinoma. Pancreatico-duodenectomy was performed for the tumor. Macro-scopically, the tumor measured 9.0×6.0 cm in the size, occupying the whole lumen of the duodenum. Micro-scopically, adenocarcinoma limited to the submucosa and adenoma were observed partially along with the carcinoma. Immunohistochemically, they were negative for mutant p53 protein.

　Early duodenal cancer is relatively rare and, in size, this case is the largest early duodenal cancer to be reported in Japanese medical literature. Moreover, the symptom due to obstruction of the duodenum in this case is also rare for early cancer.