Interesting info found on Cancer Treatment Center of America website

Extrahepatic Bile Duct Cancer Risk Factors
Carcinoma of the extrahepatic bile duct is slightly more common in males, and most often occurs in between the ages of 50 and 60.
The following are some possible risk factors for extrahepatic bile duct cancer:

-Having chronic ulcerative colitis or certain diseases of the liver and bile duct
History of Primary Sclerosing Cholangitis (PSC): This is thought to be an autoimmune disorder, one in which the body’s own inflammatory cells attack the bile ducts. PSC causes progressive scarring and narrowing of the bile ducts, which block bile from reaching the intestines. Many patients eventually develop liver failure, necessitating a liver transplant. About 10 to 20 percent of patients with PSC will develop bile duct carcinoma. It is thought that the progressive epithelial injury and subsequent regeneration predisposes patients with PSC to carcinoma. More than half of patients with PSC have a history of another autoimmune disorder, idiopathic inflammatory bowel disease.
-Congenital abnormalities (abnormalities one is born with) of the bile ducts: These include choledochal cysts (dilation of the common bile duct) and Caroli’s disease (dilation of the intrahepatic bile ducts). It is thought that prolonged sludging of bile in these dilated spaces, and subsequent infection, predispose patients to carcinoma through progressive epithelial injury and repair. The overall lifetime risk of cholangiocarcinoma in these patients is about 10 percent.
-Benign tumors of the bile ducts: This includes bile duct adenomas (a single tumor) or bile duct papillomatosis (multifocal)
-Hepatobiliary parasitic infection: These cases are most often seen in the Far East and include Clonorchis sinensis (most prevalent in Japan, Korea, and Vietnam) and Opisthorchis viverrini (most prevalent in Thailand, Laos, and Malaysia). Clonorchis is acquired when humans eat fresh water fish that harbor the Clonorchis cyst. The cysts develop into flukes (flatworms) in the friendly confines of the human intestine, and ascend from the duodenum (the first part of the intestine) into the common bile duct, where they mature. Carriage of this worm imparts a 25 to 50 risk of developing biliary tract carcinoma.
-Toxic exposures: Thorium dioxide (Thorotrast), which was used as a contrast dye in radiologic procedures between 1930 and 1950, has been shown to promote cancers in the liver and bile ducts.

My mom was in a terrible car accident in 1951. She had a head injury, and we are SURE that she had to have xrays. We just wonder about the last risk factor listed, Thorium dioxide.

Just something to ponder……
Amy