Diagnostic Ultrasound - Abdomen and Pelvis

Cholangiocarcinoma
Diagnoses: Biliary System
TERMINOLOGY
• Malignancy that arises from intrahepatic bile duct (IHBD) or
extrahepatic bile duct epithelium
IMAGING
• Best diagnostic clue:Intra- or extrahepatic bile duct mass
with upstream bile duct dilatation
• Intrahepatic cholangiocarcinoma
○ Mass with ill-defined margin, heterogeneous
echotexture
○ Isolated thickening of IHBD or intraductal mass, with
upstream ductal dilatation
• Hilar cholangiocarcinoma
○ Nonunion of right and left hepatic ducts
○ Primary tumor may not be discernible, or appears as
small, infiltrative iso-/hyperechoic mass in hilar region
• Extrahepatic cholangiocarcinoma
○ Proportional bile duct dilatation
KEY FACTS
– Primary tumor often undetectable due to its deep
location
○ Ill-defined, solid, heterogeneous mass within or
surrounding duct at point of obstruction
○ Polypoidal intraluminal tumor visible as iso-/hyperechoic
mass within bile duct
TOP DIFFERENTIAL DIAGNOSES
• Pancreatic head adenocarcinoma
• Choledocholithiasis
• Recurrent pyogenic cholangitis
• Primary sclerosing cholangitis
• Porta hepatis tumor
PATHOLOGY
• Pathogenesis:Biliary intraepithelial neoplasm is considered
premalignant lesion
(Left) Graphic shows an
infiltrative mass at the
confluence of the right and
left hepatic ducts (Klatskin
tumor). The mass invades
adjacent liver parenchyma and
hepatic veins , a common
finding with
cholangiocarcinoma. Note
upstream dilatation of
intrahepatic bile ducts .
(Right) Transverse abdominal
grayscale ultrasound shows an
ill-defined isoechoic
cholangiocarcinoma at the
hepatic confluence associated
with marked left intrahepatic
ductal dilatation st.
(Left) Color Doppler
ultrasound performed in the
same patient confirms tubular
structures are indeed dilated
intrahepatic bile ducts st
caused by an isoechoic
cholangiocarcinoma involving
the hepatic confluence .
(Right) Isoechoic polypoid
intraluminal
cholangiocarcinoma in the
distal common bile duct is
seen on this transverse view of
the common bile duct at the
level of the pancreatic head.
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