Gallbladder cancer and cholangiocarcinoma

• Biliary tract cancers are a family of uncommon but aggressive cancers: cancer of the gallbladder and cholangiocarcinoma, which is cancer of the bile ducts.
• Cholangiocarcinoma is grouped by anatomy into intrahepatic (inside the liver), perihilar (at the liver hilum) and distal (lower bile duct) disease. Perihilar disease is described further with the Bismuth classification.
• Most are found late: in cholangiocarcinoma, about three quarters of patients have non-resectable or metastatic disease at presentation, and the 5-year survival of gallbladder cancer is under 20%. ^[2][3]
• Surgery is the only chance of cure. Where surgery is not possible, the backbone of treatment is chemotherapy, now combined with immunotherapy, plus stenting to relieve jaundice.
• Risk is raised by chronic inflammation of the gallbladder and bile ducts: gallstones, porcelain gallbladder, primary sclerosing cholangitis and liver fluke infection are the classic examples.

By the end of this page you should be able to:

1. Name the anatomical types of biliary tract cancer and the Bismuth classes of perihilar cholangiocarcinoma.
2. Link each major risk factor to the cancer it predisposes to.
3. Choose and interpret the first investigations, including carbohydrate antigen 19-9 (CA 19-9) and the main imaging studies.
4. Outline the treatment algorithm: resection, biliary drainage and stenting, adjuvant therapy, and first-line systemic therapy.
5. Explain how palliative options such as metallic stenting and chemotherapy are used, and why biliary drainage matters.
6. Recognise the serious mimics and complications, including cholangitis, hepatic decompensation and recurrent stricturing.

Biliary tract cancers are aggressive. They are uncommon in global terms, and they behave aggressively because they sit deep in the liver hilum, present late, and resist many systemic treatments. This page treats gallbladder cancer and cholangiocarcinoma together, because they share anatomy, investigation and drug therapy, while highlighting where they differ. The page uses current guideline editions that are openly available: the ESMO Clinical Practice Guideline interim update of December 2024, the NCCN Biliary Tract Cancers guideline Version 2.2025, NICE guidance, the WHO advice on liver flukes, and StatPearls summaries. ^[1][2][3][4]

Anatomically, cholangiocarcinoma (CCA) is the cancer of the bile duct epithelium. ^[3] It is classified by site:

• Intrahepatic cholangiocarcinoma (iCCA): arises within the liver, proximal to the second-order bile ducts. It often presents as a liver mass.
• Perihilar (hilar) cholangiocarcinoma (pCCA): arises in the common hepatic duct or its bifurcation. This is the classic "Klatskin" tumour.
• Distal cholangiocarcinoma (dCCA): arises in the common bile duct, usually near the ampulla of Vater.

Gallbladder cancer is usually adenocarcinoma arising from the gallbladder mucosa. Most gallbladder cancers are adenocarcinomas, with squamous, adenosquamous and neuroendocrine tumours less common. ^[2] It begins on the luminal surface: the gallbladder has no submucosa, so early invasion into the muscle wall occurs quickly. ^[2]

The Bismuth-Corlette classification describes how far a perihilar tumour has spread along the hepatic ducts and is central to deciding resectability. ^[1]

A complementary histological distinction matters for intrahepatic disease: small-duct and large-duct iCCA behave differently and differ in molecular profile, and liver-fluke-associated disease usually shows large-duct morphology. Modern guidelines therefore ask for molecular profiling of advanced disease before starting systemic therapy. ^[1]

Biliary tract cancer is a small fraction of human cancer as a whole. Cholangiocarcinoma is the second most common primary liver cancer in most series, and gallbladder cancer is the most common anatomic subtype of biliary tract cancer. ^[4] Gallbladder cancer is more common in women. ^[2] Incidence varies steeply by geography: gallbladder cancer is unusually common in some South American and North Indian populations, and liver-fluke cholangiocarcinoma clusters in parts of Southeast Asia. ^[6]

Five-year survival is poor: under 20% for gallbladder cancer, and the overall figure for cholangiocarcinoma is poor because of late presentation. ^[2][3]

The unifying story is chronic inflammation plus stasis: irritated epithelium cycles through metaplasia and dysplasia to invasive cancer over years or decades.

• Gallstones. Long-standing stone disease is the dominant risk association for gallbladder cancer, through chronic mechanical and chemical irritation of the mucosa.
• Porcelain gallbladder. Calcification of the gallbladder wall is a marker of chronic cholecystitis and is treated as a precancerous condition; it is an indication for cholecystectomy.
• Gallbladder polyps and adenomyomatosis. Larger polyps and some familial polyposis syndromes need follow-up; cholecystectomy is advised for polyps that are large or growing (exact cut-offs vary by guideline).
• Chronic infection. Salmonella Typhi carrier state and Helicobacter species have been associated in endemic areas.
• Obesity, female sex and reproductive factors increase the risk of gallstones and therefore of gallbladder cancer.
• Union of pancreatic and biliary ducts (anomalous pancreaticobiliary junction) allows pancreatic juice to reflux into the gallbladder and predisposes to cancer at a young age.

• Primary sclerosing cholangitis (PSC). PSC is a chronic, progressive stricturing disease of the intrahepatic and extrahepatic bile ducts, usually associated with inflammatory bowel disease. It is the strongest single risk factor in Western populations: affected patients have roughly 400 times the risk of cholangiocarcinoma of the general population, a yearly incidence of about 1% to 1.5%, a lifetime risk up to 20%, and long-term risks of about 6% at 10 years, 14% at 20 years and 20% at 30 years. About 27% to 37% of cholangiocarcinomas in PSC are found within the first year after the diagnosis is made. ^[7]
• Liver flukes. Chronic infection with Clonorchis sinensis or Opisthorchis viverrini (from eating raw or undercooked freshwater fish) causes chronic biliary inflammation and is classified as carcinogenic to humans; these flukes account for much of the world's burden of cholangiocarcinoma. ^[6] Opisthorchis felineus has not been established as a carcinogen. ^[6]
• Bile duct stones and congenital cystic disease. Hepatolithiasis, choledocholithiasis (especially large or long-standing stones), choledochal cysts and Caroli disease all raise risk; larger stones and longer illness raise it further. ^[3]
• Viral hepatitis and cirrhosis are risk factors for intrahepatic cholangiocarcinoma, as is non-alcoholic fatty liver disease.
• Other exposures include asbestos, thorium dioxide (Thorotrast, historical), dioxins and 1,2-dichloropropane. Tobacco and alcohol contribute modestly.
• Choledocholithiasis and chronic cholangitis from any cause are additional risk factors. ^[7]

Some of these factors are modifiable or treatable, which is the basis for prevention. ^[3][5][6]

The mechanism explains everything a student later needs to remember.

Gallbladder cancer. A stone (or fluke, or refluxed pancreatic juice) irritates the mucosa for years. The mucosa undergoes intestinal metaplasia, then dysplasia, then carcinoma in situ, then invasion through the thin muscle layer into the serosal surface, liver bed and nodes. Because the gallbladder is a thin-walled reservoir with no submucosa, invasion is early and often silent until the tumour either obstructs the cystic duct or spreads to adjacent liver.

Cholangiocarcinoma. The normal biliary epithelium is exposed to chronic irritants (bile acids, fluke excretions, immune complexes in PSC). The epithelium proliferates, develops dysplasia, and is at increased risk of exposure to nitrogen compounds and inflammatory mediators (interleukin-6, tumour necrosis factor, and cyclooxygenase-2) that drive proliferation and DNA damage. ^[7] Over years, dominant strictures, dysplasia and finally invasive adenocarcinoma result. Tumours grow along the duct wall and infiltrate periductal tissues early, which is why even "small" perihilar tumours can encase the portal vein or hepatic artery.

Why symptoms follow anatomy. An intrahepatic tumour grows as a liver mass first and causes mass effect (pain, anorexia, weight loss) and may only cause jaundice late. A perihilar tumour blocks bile drainage from both hemilivers early, so jaundice and cholangitis appear early and are often the presenting complaint. A distal tumour blocks the common bile duct above the ampulla, causing jaundice and often gastric outlet-type symptoms when it is bulky. Gallbladder cancer obstructs the cystic duct first, so early cancer can masquerade as recurrent biliary colic or acute cholecystitis.

Both tumours are overwhelmingly adenocarcinomas. Cholangiocarcinomas are adenocarcinomas in the great majority of cases (more than 90%). ^[4] Most gallbladder tumours are also adenocarcinomas, with squamous, adenosquamous and neuroendocrine tumours less common. ^[2]

Molecular differences are increasingly used to choose treatment. Small-duct intrahepatic disease is enriched for potentially actionable alterations (for example IDH1 mutations, FGFR2 fusions, BRAF V600E), while extrahepatic and gallbladder disease is more often associated with HER2 amplification or over-expression (HER2 alterations occur in roughly 5–10% of biliary tract cancers). ^[1]

Early disease is often silent or mimics gallstone disease. Symptoms, when they appear, are non-specific:

• Right upper quadrant pain, often mistaken for biliary colic or chronic cholecystitis.
• Anorexia, weight loss, nausea and fatigue.
• Palpable gallbladder mass ("Courvoisier's gallbladder") or a hard liver edge.
• Jaundice only when the tumour involves the hilum or common duct.

Because the gallbladder has no submucosa, metastasis to regional nodes and direct invasion of the liver bed occur early. ^[2]

Presentation depends on the level of obstruction:

• Intrahepatic: dull right hypochondrial pain, hepatic mass on imaging, anorexia, weight loss, sometimes fever. Jaundice is late.
• Perihilar: progressive painless jaundice, pale stools, dark urine, pruritus, possibly fever and rigors from ascending cholangitis. This is the commonest presentation.
• Distal: obstructive jaundice with a distended, palpable gallbladder in some patients; steatorrhoea from malabsorption of fat; duodenal compression later.

Red flags that should prompt urgent referral include painless jaundice in an older patient, a gallbladder mass, recurrent cholangitis without stones, and rapidly rising bilirubin.

First-line tests include liver biochemistry (bilirubin, alkaline phosphatase, gamma-glutamyl transferase, transaminases, albumin and prothrombin time), renal function, full blood count, CA 19-9 and, where raised, CEA. ^[3] CA 19-9 is a tumour marker excreted by biliary epithelium that helps to assess disease burden and monitor response, but it is not diagnostic: it can be high in cholangitis, obstruction and PSC. ^[3]

Imaging ladder

• Transabdominal ultrasound is the first test for jaundice and for any gallbladder abnormality. It detects stones, mural thickening, polyps and liver masses, and can show dilated ducts.
• Multiphasic CT of the chest, abdomen and pelvis stages disease and looks for arterial encasement, nodal disease and distant metastasis.
• MRI with MRCP is the best non-invasive test for duct anatomy: it shows stricture level, ductal dilatation and intrahepatic extent, and it helps to define perihilar resectability.
• Endoscopic ultrasound (EUS) evaluates distal lesions, nodal disease and local vascular invasion, and allows fine-needle aspiration.
• ERCP allows brushings and biopsies, balloon or bougie dilatation and stent placement. Percutaneous transhepatic cholangiography (PTC) is used when ERCP fails or for proximal drainage.
• PET-CT is used selectively to detect nodal or distant disease in surgical candidates.

Tissue diagnosis

• Brush cytology and biopsy at ERCP or PTC have modest sensitivity; a negative result does not exclude cancer.
• Where the diagnosis is strongly suspected on imaging and the patient is a surgical candidate, surgery may proceed without a pre-operative biopsy, because biopsy risks seeding and treatment is driven by resectability. ^[3]
• All patients should be screened for distant metastatic disease with CT of chest, abdomen and pelvis. ^[3]
• Diagnostic laparoscopy is often performed before laparotomy because imaging misses some metastases.

Molecular testing

For advanced disease, molecular profiling is essential before starting systemic therapy; panels should include IDH1, FGFR2, BRAF, HER2, NTRK, RET, BRCA1/2 and PALB2 targets. ^[1]

There is no blood or imaging criterion that by itself proves the diagnosis. Diagnosis is a synthesis of clinical picture, cholestatic biochemistry, imaging showing a stricture or mass, and, where possible, cytology or histology. ^[3]

Staging uses the TNM system, applied separately to gallbladder cancer, intrahepatic and extrahepatic cholangiocarcinoma. Resectability is decided by a multi-disciplinary team on the basis of:

• Local extent into the liver hilum, portal vein and hepatic artery.
• Anticipated residual liver volume after resection.
• Nodal and distant metastasis.

The Bismuth type predicts the hepatic resection (minor or major hepatectomy, usually with caudate lobe resection, for types III and IV). ^[1]

The management pathway follows the algorithm below. It separates potentially curative surgery, which is the priority, from palliation of obstruction and systemic therapy.

Surgery is the only curative treatment modality; radiation and chemotherapy are adjuncts. ^[3]

• Gallbladder cancer. A very early cancer found incidentally after cholecystectomy may need no further surgery. More invasive disease generally needs re-resection with wedge removal of the liver bed and regional lymphadenectomy. Jaundice, nodal disease beyond the hepatoduodenal ligament, or distant metastasis usually precludes curative surgery.
• Intrahepatic cholangiocarcinoma. Anatomical hepatic resection with lymphadenectomy, preserving an adequate future liver remnant. The caudate lobe may need resection.
• Perihilar cholangiocarcinoma. Major hepatectomy (extended left or right), caudate lobe resection, extrahepatic bile duct resection and lymphadenectomy, often after portal vein embolisation to grow the future remnant. Liver transplantation within strict protocols is used in some centres for unresectable perihilar disease.
• Distal cholangiocarcinoma. Standard pancreaticoduodenectomy (Whipple procedure) with lymphadenectomy.
• Palliative surgery. Bypass procedures (hepaticojejunostomy) are used when stenting is not possible.

Obstructive jaundice must be relieved before and during treatment: it is a prerequisite for safe chemotherapy and markedly improves symptoms and cholestasis. NICE guidance on gallstone disease summarises the principle: if the bile duct cannot be cleared by ERCP, biliary stenting is used to achieve drainage as a temporary measure until definitive clearance. ^[5] The same principle applies in malignant obstruction, though malignant strictures are not clearable.

• Endoscopic placement (ERCP) with a self-expanding metal stent is preferred for durable palliation. Metal stents stay open longer than plastic stents; plastic stents are used for temporary drainage, for bridging to surgery, or when life expectancy is very short.
• Percutaneous transhepatic drainage is used when endoscopic access fails (high obstruction or failed ERCP) and can be internalised as a metal stent later.
• Multifocal hilar obstruction often needs bilateral (Y- or T-shaped) stenting.
• Cholangitis on a stent needs urgent decompression plus antibiotics; stents block and need replacement.

For advanced or metastatic disease, first-line treatment is now cisplatin-gemcitabine with an immune checkpoint inhibitor, on the evidence of ESMO's December 2024 interim update: both cisplatin-gemcitabine-durvalumab and cisplatin-gemcitabine-pembrolizumab are recommended as first-line therapy (grade I, A). ^[1] In the KEYNOTE-966 trial, adding pembrolizumab to cisplatin-gemcitabine gave a median overall survival of 12.7 months versus 10.9 months with placebo (hazard ratio 0.83). ^[1] There is no biomarker that clearly favours one checkpoint inhibitor over the other. ^[1] Where performance status is poor, or the patient is vulnerable to platinum toxicity, gemcitabine alone can be considered. ^[1]

Where disease is gemcitabine-cisplatin resistant:

• FOLFOX (oxaliplatin, 5-fluorouracil and folinic acid) versus active symptom control improved survival in a randomised trial in previously treated patients (the ABC-06 study, an abstract-level source used by ESMO). ^[1]
• Targeted therapy is now central to second and later lines, chosen by molecular profile: ^[1]
  • FGFR2 fusions or rearrangements (mainly intrahepatic): futibatinib or pemigatinib.
  • HER2 over-expression or amplification: zanidatamab (and trastuzumab deruxtecan where available).
  • IDH1 R132 mutations: ivosidenib.
  • NTRK fusions: entrectinib, larotrectinib or repotrectinib.
  • RET fusions: selpercatinib.
  • MSI-high or dMMR disease: anti-PD-1 therapy (pembrolizumab) in previously untreated by immunotherapy; dMMR lesions can also respond to targeted approaches directed at the altered pathway.
• Radiotherapy. SBRT or chemoradiation can improve local control, relieve pain and, after carefully selected response, allow downstaging toward surgery. ^[4]

Adjuvant therapy after resection is generally offered (capecitabine-based regimens are common), and the NCCN panel places emphasis on adjuvant chemotherapy and chemoradiation for biliary tract cancer because recurrence is the principal limitation on cure. ^[4]

• Biliary obstruction and cholangitis, the commonest problems, from tumour, stone or stent blockage. Emergency decompression is required.
• Liver failure from advanced intrahepatic replacement or prolonged obstruction of a small liver remnant.
• Post-operative morbidity: bleeding, bile leak, liver abscess, pneumonia. Major hepatectomy for perihilar disease carries significant risk and needs specialist centres.
• Sepsis from an infected biliary system or blocked stent.
• Metastatic complications: bone pain, brain metastases, duodenal obstruction from distal disease.
• Treatment complications: chemotherapy toxicity (myelosuppression, neuropathy, fatigue); cholangitis on a blocked stent.

Prognosis is stage-dependent and generally poor. Gallbladder cancer has a 5-year survival under 20%. ^[2] Cholangiocarcinoma has an overall poor prognosis because about three quarters of patients (and a higher proportion of those with perihilar disease) present with non-resectable or metastatic disease. ^[3] After complete (R0) resection, 5-year survival is markedly higher, which is why aggressive surgery is justified in fit patients in specialist centres.

• Gallbladder cancer: prevent gallstones where possible, treat symptomatic stones with cholecystectomy, and avoid the metaplasia-dysplasia sequence in high-risk states (resect porcelain gallbladder; resect or surveil gallbladder polyps according to size and growth). ^[5]
• Cholangiocarcinoma: liver-fluke prevention (cook freshwater fish thoroughly, safe fish farming, sanitation) is the single most effective public health measure in endemic regions. ^[6] Vaccination against hepatitis B and C reduces intrahepatic risk.
• PSC surveillance: patients with PSC need regular imaging (MRI/MRCP or ultrasound) at least yearly and often every 6 to 12 months, plus CA 19-9, to detect cholangiocarcinoma and gallbladder cancer early. ^[7]
• There is no population screening for gallbladder or bile duct cancer outside these high-risk groups.

• Older and frail adults. Performance status and comorbidity determine whether combination chemotherapy is possible. Where it is not, single-agent gemcitabine or best supportive care is used. ^[1]
• Patients with jaundice and cholangitis. Relieve obstruction first; do not give systemic therapy into obstructed, infected biliary trees.
• Coincidental gallbladder cancer after cholecystectomy. Early lesions may need no further treatment; more advanced lesions need staging resection. This should be discussed in a hepato-pancreato-biliary tumour board.
• Hereditary and familial risk. Patients with PSC, familial adenomatous polyposis or anomalous biliary junction need individualised plans.
• Low- and middle-income regions. Liver-fluke disease dominates; community chemotherapy with praziquantel, safe food practice and sanitation are the effective public-health tools. ^[6]

• Ultrasound is the essential first test; it detects gallbladder masses and obstructed, dilated ducts even where CT and MRI are unavailable.
• Where ERCP and metal stents are unavailable, surgical bypass or percutaneous drainage by trained clinicians provides the same life-saving decompression.
• Staging information is often incomplete; clinical assessment (jaundice, mass, ascites, performance status) plus a single CT still allows a plan.
• Pathology may be limited; basic histology (adenocarcinoma versus other) supports most decisions, though molecular testing is usually impossible. Chemotherapy backbones (gemcitabine and 5-fluorouracil) are widely available.
• Refer early to a centre that can offer hepato-pancreato-biliary surgery and oncology wherever possible.

• Biliary tract cancers are gallbladder cancer and cholangiocarcinoma (intrahepatic, perihilar and distal). Perihilar extent is described with the Bismuth classification.
• Chronic inflammation drives the disease: gallstones, porcelain gallbladder, primary sclerosing cholangitis and liver flukes are the key risk factors.
• Cholangiocarcinoma is usually adenocarcinoma (more than 90% of cases). Gallbladder cancer is also predominantly adenocarcinoma. ^[4][2]
• About three quarters of cholangiocarcinomas are unresectable at presentation, and 5-year survival for gallbladder cancer is under 20%. ^[3][2]
• Surgery is the only curative option: cholecystectomy-based resection, hepatic resection, or pancreaticoduodenectomy depending on anatomy.
• Biliary drainage by stenting is a pre-requisite for safe chemotherapy and palliates jaundice; metal stents are preferred for durable palliation. ^[5]
• First-line systemic therapy for advanced disease is cisplatin-gemcitabine plus an immune checkpoint inhibitor (durvalumab or pembrolizumab). ^[1]
• Molecular profiling (IDH1, FGFR2, HER2, BRAF, NTRK, RET, MSI/dMMR) changes second-line and later treatment. ^[1]
• CA 19-9 is the characteristic marker but is not diagnostic; imaging (ultrasound, then CT and MRI/MRCP) does the structural assessment. ^[3]
• PSC carries a lifetime cholangiocarcinoma risk up to 20% and needs surveillance imaging at least yearly. ^[7]
• Liver-fluke prevention (cooking fish, sanitation) is the leading public health measure in endemic regions. ^[6]
• Outcomes remain poor without early detection; the whole pathway depends on timely referral for jaundice.

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