2022 Volume 36 Issue 2 Pages 113-120
Assessment of longitudinal extent of distal bile duct cancer, especially at hepatic site, is essential to determine the resectability, extent of resection, and surgical methods. The extension patterns of the tumors are divided into mucosal and intramural extension. The macroscopic appearances of the tumors are categorized into papillary type, nodular type, and flat type, and each type is divided into filling type and invasive type. The papillary type and nodular filling type (so called localized type) mainly present mucosal extension, and the nodular type and flat type (so called invasive type) mainly present intramural extension. On the image findings, intramucosal extension is expressed by the thickening and rigidity of the bile duct wall and luminal stenosis. These finding are evaluated by MDCT, MRI/MRCP, EUS, ERCP, and IDUS. On the other hand, it has been difficult to assess the mucosal extension because it shows flat extension. However, recently, several reports suggested the usefulness of POCS with mapping biopsy, and it is becoming popular.
