Usually discovered coincidentally in patients with cholecystitis (about 90% have gallstones), gallbladder and bile duct cancers account for less than 1% of all cancer cases. The predominant type is adenocarcinoma (responsible for 85% to 95% of cases). Squamous cell carcinoma accounts for between 5% and 15%. Mixed-tissue types are rare.

Gallbladder cancer is most prevalent in females older than age 60. And because it’s usually discovered after cholecystectomy and at an advanced stage, the prognosis is poor. If the cancer invades the gallbladder musculature, the survival rate is less than 5%, even after extensive surgery. Although some long-term survivals (4 to 5 years) have been reported, few patients survive more than 6 months after surgery. The disease progresses rapidly in most patients—with or without surgery. Patients seldom live more than 1 year after diagnosis.

Carcinoma of the extrahepatic bile duct causes less than 3% of all cancer deaths in the United States. This cancer typically occurs in individuals between ages 60 and 70 and affects more males than females. The usual site is the bifurcation in the common bile duct. About 50% of patients also have gallstones. Metastasis affects local lymph nodes, the liver, the lungs, and the peritoneum. Patients typically die of hepatic failure. No staging protocol exists for this type of cancer.