If you or your child has just been told the words “choledochal cyst”, you probably have a long list of questions and very little time to ask them. Most people have never heard of this condition before the day they are diagnosed, and a first internet search can turn up information that is frightening, technical or out of date.
This page answers the questions we hear most often, in plain English, drawing on paediatric hospitals, liver charities and the published medical literature. We are a patient-led community: parents who sat in a hospital corridor holding a scan result they did not understand, and adults diagnosed later in life. The answers are grouped so you can jump to what matters right now.
A choledochal cyst is a rare, usually congenital swelling of one or more bile ducts, the small tubes carrying bile from the liver and gallbladder into the intestine. Cleveland Clinic describes it as a condition that causes one or more of your bile ducts to widen or enlarge. It is not a tumour, and not a cyst in the sense of a lump under the skin. The duct wall itself is stretched, so bile drains slowly and can back up, become infected or form stones. Because that abnormal tissue carries a long-term cancer risk, the usual treatment is removal.
Genuinely rare. In Western countries, reported incidence is roughly 1 in every 100,000 to 150,000 live births, with the United States figure often quoted as about 1 in 13,500. In parts of East Asia it is far more common, with Japanese figures approaching 1 in 1,000, and between a third and two-thirds of all reported cases come from Japan. Girls and women are affected around three to four times more often than boys and men. Rarity is one reason families feel isolated, and one reason our community exists.
Doctors use the Todani classification, which sorts them into five main types by location. Type I, a widening of the bile duct outside the liver, is by far the most common at roughly 80 to 90 per cent of cases in radiology series. Type II is a pouch off the side of the duct, type III (a choledochocele) sits where the duct enters the duodenum, type IV involves ducts inside and outside the liver, and type V is Caroli disease. We explain each on our types pages, including type I.
Yes, more often than people expect. StatPearls notes that while most are found in childhood, around 25 per cent are discovered in adults. Adults more often present with abdominal pain or pancreatitis than with the classic childhood picture of jaundice and a palpable lump, and the cyst is sometimes an incidental finding on a scan done for something else. Adults have usually had the condition longer, which is why long-term complications are reported in around 30 per cent of adults compared with about 9 per cent of children. See our full page on choledochal cysts in adults.
Nobody knows for certain, and it is worth saying that clearly. The leading explanation is a plumbing problem present before birth: the pancreatic duct and bile duct join further back than they should, outside the muscular valve that normally keeps them separate. Pancreatic juice then washes back into the bile duct, weakening the wall until it stretches, while a narrowing lower down adds back-pressure. Nothing a parent did during pregnancy causes this. It is not linked to diet, medication or stress.
In almost all cases, no. Choledochal cysts occur sporadically, meaning they appear in one person with no family history and no identified inherited gene. Liver UK notes that while they might run in families, other factors are also involved and the condition is not purely hereditary. A small number of published case reports describe siblings, or a parent and child, both affected, but these are rare enough to be individually notable in the literature. The clear exception is Caroli syndrome, which does follow an inherited pattern.
Pancreaticobiliary maljunction, often shortened to PBM, is the abnormal joining of the bile duct and pancreatic duct outside the wall of the duodenum. This creates an unusually long shared channel that the sphincter muscle cannot control. Some published series have found this anomaly in 90 to 100 per cent of patients with choledochal cysts, which is why many specialists regard it as the underlying cause rather than an incidental finding. It matters after surgery too, because the maljunction itself is linked to increased biliary cancer risk.
The cyst itself is not cancer, but the abnormal duct lining carries a real risk of becoming cancerous over time. StatPearls puts the overall malignancy risk at approximately 5 per cent, while a meta-analysis of 2,904 cases found around 11 per cent of patients developed a malignancy; other reviews quote ranges as wide as 9 to 28 per cent. Cholangiocarcinoma in people with choledochal cysts appears at a median age of 49.5 years, against 65 in people without. This risk, not the symptoms, drives the advice to operate. See our page on complications.
The textbook triad is abdominal pain, jaundice (yellowing of the skin and eyes) and a lump felt in the upper right abdomen, but all three together appear in only about 10 to 20 per cent of patients. Far more often people have one or two: episodes of upper abdominal pain, nausea and vomiting, fever, itching, pale stools, dark urine or unexplained weight loss. Babies may have jaundice that does not settle. Some cysts cause no symptoms at all. Our symptoms page covers these in detail.
Usually an abdominal ultrasound comes first, because it is quick, painless and radiation-free; reported sensitivity ranges from about 71 to 97 per cent. The picture is then confirmed with MRCP, a specialised MRI of the bile ducts, which is 90 to 100 per cent sensitive and maps the anatomy surgeons need without anything going inside the body. CT, endoscopic ultrasound, ERCP or a HIDA scan are used in selected cases, alongside blood tests. Our diagnosis page explains what each scan involves.
Sometimes, yes. Cleveland Clinic and Children’s Hospital of Philadelphia both confirm a choledochal cyst may first be spotted on a routine prenatal ultrasound, typically as a cyst near the fetal liver, though CHOP notes this happens only in rare cases. A prenatal finding is not an emergency and does not usually change how or when a baby is delivered. It does mean the baby will be scanned after birth to confirm the diagnosis and distinguish it from biliary atresia, which is treated very differently and far more urgently.
It can, but it is uncommon. Reported rates of spontaneous perforation sit between about 2 and 12 per cent of children with choledochal cysts, and it is strongly age-related: around 15 per cent in infants, falling to roughly 4 per cent in children over ten. Warning signs are sudden severe abdominal pain, fever, a swollen tender abdomen and a child who is clearly unwell. It is treatable, but needs immediate hospital assessment, so trust your instincts.
Caroli disease is the type V choledochal cyst: multiple sac-like dilatations of the bile ducts inside the liver. It is extremely rare, affecting roughly 1 in a million people. When it occurs with congenital hepatic fibrosis it is called Caroli syndrome, inherited in an autosomal recessive pattern through the PKHD1 gene and often accompanying autosomal recessive polycystic kidney disease. Because the affected ducts sit throughout the liver, treatment may mean removing part of the liver or, in diffuse disease, transplantation. Cholangiocarcinoma occurs in around 7 per cent. See type V.
For the common types, no. The standard position in the surgical literature is that all cysts should be resected and bile flow restored, because leaving abnormal duct tissue in place means ongoing risk of cholangitis, pancreatitis, stones and cancer. This applies to adults with no symptoms too. There is one partial exception: type III choledochoceles are sometimes managed endoscopically with a sphincterotomy. Antibiotics, drainage or stenting may settle an infection first, but they are holding measures, not a cure. Read more on treatments.
It is the reconstruction that follows removal of the cyst. Once the abnormal duct is out, the surgeon needs a new route for bile to reach the intestine. A section of small bowel called the jejunum is divided, and one limb is joined directly to the healthy bile duct near the liver, with the other end reconnected further down to form a Y shape. Bile then flows straight into the bowel, bypassing where pancreatic juice used to reflux. It carries lower rates of later malignant change than joining the duct to the duodenum.
Yes, in type I and type IV cysts the gallbladder comes out during the same operation. It sits on the cystic duct, which drains into the affected section of bile duct, so it has to be removed with it. It is also abnormal tissue in its own right, and in people with pancreaticobiliary maljunction it carries a raised cancer risk. Living without a gallbladder is very manageable: bile drips continuously into the bowel instead of being stored, which some people notice as looser stools after fatty meals.
Longer than most families expect, and that is normal. In a published series of children having laparoscopic cyst excision with Roux-en-Y reconstruction, operating time ranged from around 235 to 460 minutes, averaging roughly five hours. Open surgery is often somewhat quicker, and times vary with the child’s age, cyst type, previous infection and scarring, and the surgeon’s experience. Add time either side for anaesthetic and recovery, so expect a whole day at the hospital. Our pre-surgery page covers what to pack.
Untreated, the cyst tends to cause repeated problems while the cancer risk accumulates. Common consequences include ascending cholangitis (infection of the bile ducts), pancreatitis, stones inside and outside the liver, biliary obstruction, liver scarring and, in a minority, rupture. The malignancy risk is decisive: patients who had drainage only, without removal of the cyst, had roughly four times the risk of developing cancer compared with those whose cyst was excised.
Hospital stay after laparoscopic surgery is quoted as three to five days by CHOP, and Seattle Children’s gives an average of about seven days overall. Open surgery usually adds several days. Most children are eating, walking and playing gently within one to two weeks and back at school in three to four. Full internal healing takes about six weeks, so heavy lifting and sport wait for clearance. See post-operative care.
Generally no. Liver UK is explicit that no specialised diet is required after choledochal cyst surgery, and most people return to completely normal eating. In the first few weeks, small frequent meals and going gently on very fatty or fried food often feels more comfortable, particularly with the gallbladder gone, and that can persist for a few months. If someone has significant liver involvement, or struggles to digest fats or gain weight, ask for a dietitian referral rather than restricting food alone.
For the great majority, yes. Once the cyst is removed and bile drains normally, most children grow, eat, play sport and go on to work and have families with no day-to-day restrictions. Liver UK notes that most children who have surgery recover fully without long-term complications. The main lasting differences are regular check-ups and knowing which symptoms mean get checked rather than wait and see. Many people describe the scar as the only visible reminder. Read first-hand accounts on our success stories page.
The main ones are narrowing (stricture) where the duct was joined to the bowel, episodes of ascending cholangitis, and stone formation. Long-term follow-up studies report bile duct and intrahepatic stones in a meaningful minority of patients over the years, with type IVa cysts carrying the highest complication rate. Short-term problems such as a bile leak or pancreatitis occur in a small percentage and usually settle without further surgery. Fever with jaundice or pain should always be assessed promptly.
Good, and this is the number most families want. StatPearls reports that surgical excision achieves an 89 per cent event-free rate and a five-year survival rate of 95.5 per cent, and Medscape describes the prognosis after excision as usually excellent. Figures that look alarming online, such as five-year survival around 5 per cent, refer specifically to patients who have already developed cholangiocarcinoma, not to people whose cyst was removed before cancer developed. Check which situation a statistic describes before it frightens you.
A fully excised cyst does not regrow. What can happen is that residual abnormal duct tissue was left behind, that ducts inside the liver were already involved (as in types IVa and V) and remain, or that a stricture forms at the join and causes similar symptoms. That is why complete excision is the goal and why follow-up continues. The risk of biliary malignancy stays raised even many years after treatment, so the cyst is gone does not mean monitoring stops. See our current research page.
Yes. Both CHOP and StatPearls recommend long-term follow-up with blood tests and imaging, typically yearly with a gastroenterologist or the operating surgeon, continuing into adult life. The purpose is to catch strictures, stones or cholangitis early and to monitor the small but persistent cancer risk in the remaining ducts. For Caroli disease, European guidance suggests MRCP every 12 months. Making sure your child knows their own history before they leave paediatric care matters enormously.
Honestly, the evidence here is thin. The published literature on choledochal cysts in pregnancy consists of case reports and small case series rather than large studies, so no reliable rates exist and we would be inventing numbers if we quoted any. What is reported is that pregnancy can make an untreated cyst more symptomatic, and that a cyst is occasionally mistaken for another abdominal mass on scanning. Tell your obstetric team your surgical history early and ask for hepatobiliary input.
It depends on the approach. Laparoscopic (keyhole) and robotic surgery use several small incisions, often around the belly button and across the upper abdomen, which fade to fine lines over a year or two. Open surgery uses a single longer incision under the right ribs, more visible at first but softening with time, especially in young children whose skin heals well. Your surgeon chooses the approach based on cyst type, your child’s size and any previous infection. Ask which they plan, and why.
There is no routine screening programme for siblings, and no professional body currently recommends one. Choledochal cysts occur sporadically in the overwhelming majority of cases, and the handful of published reports of affected siblings are rare enough to be individually notable in the literature. That said, if another child has unexplained jaundice, recurring upper abdominal pain or repeated episodes labelled as pancreatitis, mention the family history to your doctor and ask about an ultrasound.
If your question is not answered here, please get in touch, browse our find a doctor page, or come and ask in our community. We are parents and patients, not a call centre, and we would much rather hear from you at three in the morning before surgery than have you searching alone.
Please note: this page is general information, not medical advice. Always discuss your own or your child’s care with your medical team.
Untreated choledochal cysts can lead to several complications, including cholangitis (inflammation of the bile ducts), pancreatitis (inflammation of the pancreas), liver abscesses, and cholangiocarcinoma (bile duct cancer). Early diagnosis and treatment are crucial for preventing these complications and improving patient outcomes.
Treatment options for choledochal cysts depend on the type and severity of the cyst, as well as the presence of symptoms. In some cases, asymptomatic patients may not require treatment. However, in symptomatic patients, treatment may involve surgical resection of the cyst, reconstruction of the biliary tract, or liver transplantation in severe cases.
Choledochal cysts are typically diagnosed using imaging studies, such as ultrasound, CT scan, or magnetic resonance cholangiopancreatography (MRCP). In some cases, endoscopic retrograde cholangiopancreatography (ERCP) may also be used to diagnose and treat the condition.
There are five types of choledochal cysts, classified according to the Todani classification system. These include Type I, Type II, Type III, Type IV (subdivided into IVa and IVb), and Type V (also known as Caroli’s disease). Each type has unique characteristics and may require different approaches to diagnosis and treatment.
Choledochal cysts are rare, congenital malformations of the bile ducts, which can occur both inside and outside the liver. These cysts are fluid-filled sacs that can cause a variety of symptoms and complications if not properly treated.