Diagnosis by endoscopic ultrasonography and intraductal ultrasonography for biliary cancer

• Published in: Tando Vol. 35; no. 2; pp. 143 - 150
• Main Authors: Ito, Kei, Koshita, Shinsuke, Kanno, Yoshihide, Ogawa, Takahisa, Kusunose, Hiroaki, Sakai, Toshitaka
• Format: Journal Article
• Language: Japanese
• Published: Japan Biliary Association 31.05.2021
• Subjects: endoscopic papillectomy; ERCP; EUS; EUS-FNA; IDUS
• ISSN: 0914-0077; 1883-6879
• DOI: 10.11210/tando.35.143

The main purpose of EUS/IDUS for biliary cancer is the evaluation of tumor spreading, which can be estimated by the relationship between the tumor echo and adjacent organs such as the pancreas, the duodenum, and vessels. As for bile duct or gallbladder cancer, irregularity or interruption of the outer hyperechoic layer of the wall by EUS/IDUS suggests T2 (depth SS) or greater. In case of bile duct cancer, evaluation of lateral tumor spreading using several modalities such as CT, MRI, EUS, IDUS and ERC is indispensable for determination of the resected margin during surgical treatment. Target biopsies with the assistant of per-oral cholangioscopy are sometimes useful for preoperative examination in selected patients. Although distinguishment between T1a and T1b is difficult even by EUS/IDUS in case of ampullary cancer, invasion of the pancreatic parenchyma or the duodenal wall by the tumor and tumor extension into the bile/pancreatic duct can be estimated with both procedures, which can give an important information for determination of the indication for endoscopic papillectomy.