Cancer genes and cholangiocarcinoma.

Genes involved in cancer development include oncogenes and tumor suppressor genes. Ras oncogene and mutations in p53 tumor suppressor gene are commonly found in many types of cancer. In Thai patients with cholangiocarcinoma ras oncogenes occur less frequently than in other ethnic groups and furthermore, p53 mutations also occur with lower incidence when compared with Japanese subjects. It is unclear at this time the basis for these differences.