Gallbladder cancer: epidemiology and genetic risk associations.

Gallbladder cancer (GBC) is a form of hepatobiliary malignancy that develops from the mucosal lining of the gallbladder. The early development of gallbladder cancer is usually asymptomatic and gallbladder cancer has a high propensity to metastatic dissemination, thus most patients are diagnosed at intermediate to advanced stages for which there is no curative treatment. Consequently, gallbladder cancer is highly lethal. Though the overall global incidence of gallbladder cancer is low, there is marked geographic variation and ethnic communities in Asia as well as Native American populations in both North and South America are affected disproportionately. This article provides a comprehensive overview of the current epidemiology and risk and protective factors associated with gallbladder cancer development. In addition, the current knowledge on environmental and genetic risk associations for gallbladder cancer and the need for additional large-scale genome wide association studies (GWAS) are discussed.