Table 1.

Risk factors for cholangiocarcinoma.

General risk factors	Inflammatory risk factors
Obesity	Primary sclerosing cholangitis
Tobacco use	Hepatolithiasis
Age > 65	Biliary cirrhosis
Type II diabetes	Inflammatory bowel disease
Excessive alcohol intake	Biliary-enteric anastomosis
NAFLD	Parasitic risk factors
Congenital risk factors	Clonorchis sinensis
Caroli's disease	Opisthorchis viverrini
Choledochal cysts	Chemical risk factors
Congenital hepatic fibrosis	Nitrosamines
Bile duct adenomas	Vinyl chloride
Biliary papillomatosis	Thorotrast
Viral risk factors	Dioxin
Hepatitis B	Oral contraceptives
Hepatitis C	Isoniazid
HIV	Asbestos
	Radon