Abstract：
A man in his 70s was admitted to our hospital due to jaundice and upper abdominal pain. Laboratory findings indicated elevated serum hepatobiliary enzyme and amylase levels. Contrast-enhanced computed tomography revealed smooth wall thickening of the terminal bile duct (tBD) with a faintly enhanced inner line. ERCP revealed stenosis from the tBD to the ampulla of Vater (AV) with upstream dilatation. Intraductal ultrasound (IDUS) circumferentially revealed a thickened wall preserving a three-layered structure throughout the same region. Furthermore, a thick innermost hyperechoic layer was identified in the bile duct portion of the AV (Ab). Findings suggestive of adenocarcinoma were obtained from the tissue samples from the biliary stricture using biopsy forceps. Thus, pancreatoduodenectomy was performed. A pathological examination revealed a thickened AV wall spreading over the tBD with hyperplasia of the glands and smooth muscle fibers. In addition, low-grade biliary intraepithelial neoplasia (BilIN) was scattered throughout the lesion, and high-grade BilIN was partly observed in the peribiliary glands of the Ab. Based on these results, a diagnosis of carcinoma in situ arising in adenomyomatous hyperplasia (ADMH) of the AV was made. To date, there are no reports on ADMH-associated carcinoma of the BD or AV. We here report this original case with the IDUS findings, which are presumed to reflect the histologic features of ADMH showing ductal proliferation surrounded by smooth muscle fibers. Also, we discuss the process through which carcinoma arises from ADMH in AV.
摘要：
一名70多岁的男子因黄疸和上腹痛入院。实验室发现表明血清肝胆酶和淀粉酶水平升高。对比增强计算机断层扫描显示终末胆管（tBD）的壁光滑增厚，内线微弱增强。ERCP显示从tBD到Vater壶腹（AV）的狭窄，上游扩张。导管内超声（IDUS）周向显示出增厚的壁，在整个区域保留了三层结构。此外，在AV（Ab）的胆管部分中鉴定出最里厚的高回声层。使用活检钳从胆道狭窄的组织样本中获得提示腺癌的结果。因此，进行胰十二指肠切除术。病理检查显示，房室壁增厚，遍布tBD，腺体和平滑肌纤维增生。此外,低级别胆管上皮内瘤变（BilIN）散布在整个病变中，在Ab的胆管周围腺体中部分观察到高级BilIN。基于这些结果,诊断为由AV的腺肌瘤样增生（ADMH）引起的原位癌。迄今为止,没有关于BD或AV的ADMH相关癌的报道。我们在这里用IDUS的发现报告这个原始病例，推测反映了ADMH的组织学特征，显示被平滑肌纤维包围的导管增生。此外，我们讨论了AV中ADMH引起癌症的过程。
