Liver, gallbladder, extrahepatic bile ducts, and pancreas

Abstract
The liver, gallbladder, bile ducts, and pancreas have a common embryologic origin; cancers that arise from these sites therefore are expected to share a similar spectrum of histologic types. These cancers are known for their extremely poor prognoses. Data from the Surveillance, Epidemiology, and End Results Program regarding the incidence, distribution of histologic types, stage of disease, and survival for cancers of the gallbladder (n = 4412), extrahepatic bile ducts (n = 3486), pancreas (n = 23,116), and liver (n = 6,391) were reviewed. The most common histologic types are discussed, and the frequency of rare types is reported. The incidence of biliary cancer decreased, while the incidence of hepatic and pancreatic cancer rose slightly over the 15-year period from 1973 to 1987. Age and sex distributions varied by histologic type. Greater than 98% of pancreatic and biliary cancers were carcinomas, and adenocarcinoma (not otherwise specified) was the most common histologic type recorded. In the liver, hepatocellular carcinoma was the most common type, followed by intrahepatic cholangiocarcinoma. The overall 5-year relative survival rates for these cancers were very low: gallbladder, 12.3%; extrahepatic bile duct, 12.7%; liver 3.1%; and pancreas 2.5% (all stages combined, 1978-1986). This review confirmed that these carcinomas are associated with a very poor outcome; however, survival was influenced by stage of disease and histologic type. In the gallbladder and extrahepatic bile ducts, papillary adenocarcinoma was associated with the best outcome of all histologic types, and in the exocrine pancreas, mucinous cystadenocarcinoma was associated with the best prognosis.