KTPH Hepato–Pancreato–Biliary Surgery Service (HPB)
With improving diagnostic studies, hepatic cysts are being diagnosed more frequently. Some types of cysts are completely benign with no risk of cancer, while other types require surveillance to monitor the size and internal characteristics of the cyst to determine the risk of developing into a cancer.
Sometimes the type of cyst is not easily differentiated on the initial presentation, so repeat imaging after a time interval, or with a different modality of imaging is necessary in follow up. If an infectious or parasitic cause is suspected, blood tests will be used to identify and treat the cause.
Simple cysts (thin-walled, smooth, up to 2 septa) that are not causing symptoms of compression to the bile ducts, blood vessels or surrounding organs can be safely observed with no imaging follow up – they have no risk of developing cancer.
Symptomatic dominant cysts may require a fenestration procedure to open the cyst to drain into and be absorbed by the lining of the abdominal cavity. Diffuse multilocular cysts in polycystic liver disease (PCLD is a form of simple cysts with >20 cysts in the liver) causing compression symptoms may require resection. Most PCLD cases require no treatment at all; very rarely cases may eventually require consideration for transplantation.
Hepatic cystadenoma is a rare benign mucinous tumor (5% of liver cysts) arising from the bile ducts that can cause jaundice and cholangitis from blockage of the bile ducts and can sometimes transform into a hepatic cystadenocarcinoma cancer (0.4% of liver cysts). It is often difficult to distinguish from a hepatic cystadenocarcinoma, so these types of cyst are recommended to be removed along with a clear margin of liver in surgically fit patients.
Other uncommon forms of cysts can include Caroli's disease (bead-like areas of bile duct swelling with a 7% risk of cholangiocarcinoma), ciliated foregut cysts (subcapsular, segment IV), post-traumatic pseudocysts, biloma, peribiliary cysts (cirrhosis, portal hypertension) and cystic degeneration of a liver tumor (HCC, cholangiocarcinoma, metastasis).
