Health condition
Choledochal cysts adults
Choledochal cysts are congenital dilatations of the bile ducts increasingly diagnosed in adults on modern imaging; because they carry a significant lifetime risk of bile duct cancer, complete surgical excision is usually recommended.
Why trust this guide
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Editorial team
Written by our editorial team from the UK sources listed on each page.
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Sourced from guidance
Checked against current NHS and UK specialist society guidance at the time of review.
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Current for 2026
Reviewed on 2026-09-27 with the next review scheduled for 2027-09-27.
Key points
What matters most, at a glance.
The essentials in plain English - symptoms, when to seek help, who to see and what treatment looks like.
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Adults present with pain, recurrent cholangitis, pancreatitis or an incidental imaging finding rather than the classic childhood picture
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MRCP defines the type (Todani classification), which determines both cancer risk and surgery
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An abnormal pancreatico-biliary junction, allowing pancreatic juice to reflux into the bile duct, underlies many cysts and drives the cancer risk
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Complete cyst excision with hepaticojejunostomy - not drainage alone - is the standard operation for the common types
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Lifelong follow-up continues after excision because a small residual cancer risk remains in the biliary tree
Understanding it
About Choledochal cysts adults, and what to do next.
The refluxing junction bathes the bile duct wall in activated pancreatic enzymes for decades, and chronic injury explains a bile duct cancer risk many times the population’s, concentrated in - but not confined to - the cyst itself. This is why historical operations that merely drained the cyst have been abandoned in favour of removing it.
In adults the surgery is more demanding than in children - inflammation, prior interventions and portal hypertension complicate the field - so outcomes are best in hepatobiliary units performing these operations regularly. Asymptomatic cysts found incidentally still generally merit resection in surgically fit patients after specialist review. Most people start with their GP, who can refer to a consultant hepatobiliary surgeon. In many parts of the UK, routine NHS referrals for this kind of problem currently take 20-45+ weeks, whereas an initial private consultation is typically available within around two weeks.
A quiet reminder
This guide is for information, not medical advice.
Your GP knows your history and can tell you which parts apply to you. If in doubt, see them - and seek urgent care for any emergency symptoms described above.
Frequently asked
Common questions about Choledochal cysts adults.
Quick, plain-English answers to what people ask us most.
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What are choledochal cysts?
Choledochal cysts are abnormal dilations (widenings) of the bile duct system, present from birth, though they are sometimes not diagnosed until adulthood, particularly milder cases. They can occur at various points along the bile duct system and vary in size and shape. Adults with previously undiagnosed cysts may present with symptoms related to bile flow problems or complications developing over time.
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What causes choledochal cysts?
The exact cause is not fully understood, but they are thought to result from abnormal development of the bile ducts before birth, sometimes related to an abnormal connection between the bile duct and pancreatic duct that allows pancreatic enzymes to reflux into and weaken the bile duct wall. They are present from birth even if not diagnosed until much later in life. There is no known way to prevent their development.
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What symptoms do choledochal cysts cause in adults?
Symptoms in adults can include abdominal pain, jaundice, recurrent episodes of bile duct infection (cholangitis), and sometimes symptoms related to pancreatitis if the abnormal duct connection affects pancreatic drainage. Some cysts are found incidentally during imaging for another reason. Symptoms can be intermittent, sometimes leading to a delay before diagnosis.
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Are choledochal cysts dangerous?
Yes, they carry an increased long-term risk of bile duct cancer (cholangiocarcinoma), particularly if left untreated, in addition to the risk of recurrent infections and stone formation within the abnormal duct. This significant cancer risk is why surgical removal of the cyst is generally recommended once diagnosed, even in adults without severe symptoms. Long-term outcomes are considerably better with appropriate surgical treatment.
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How are choledochal cysts treated?
The standard treatment is surgical removal of the cyst along with reconstruction of bile flow, usually through a procedure connecting the bile duct directly to the small intestine. This is generally recommended even in adults with mild or no symptoms, given the associated cancer risk if left untreated. Surgery is typically performed by a specialist hepatobiliary surgical team.
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What is the outlook after treatment?
Outcomes are generally good following complete surgical removal, particularly when performed before cancer develops, with most people returning to normal bile duct function and diet. Ongoing monitoring is still recommended, since a small residual cancer risk can persist even after cyst removal, particularly if any abnormal tissue remains. Regular specialist follow-up helps identify and address any issues early.
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When should I see a specialist?
If a choledochal cyst is found incidentally on imaging, or you have unexplained recurrent abdominal pain, jaundice, or bile duct infections, prompt specialist hepatobiliary assessment is important. NHS hepatobiliary referral can take several weeks; a private consultation is typically available within about 2 weeks for earlier specialist input.