Hepatitis C and Risk of Nonhepatic Malignancies.

Epidemiologic studies show an increased risk of mortality among hepatitis C virus (HCV)-infected individuals compared with uninfected individuals from hepatic and nonhepatic causes. This article reviews the biologic plausibility of and epidemiologic evidence for the association between HCV and five extrahepatic malignancies: cholangiocarcinoma (CCA), pancreatic adenocarcinoma, papillary thyroid cancer, oral squamous cell cancer, and renal/kidney cancer. There is sufficient evidence to suggest that HCV is associated with intrahepatic CCA. The evidence for the link between HCV and pancreatic adenocarcinoma, oral squamous cell cancer, and renal/kidney cancer is compelling but requires further study. Based on available studies, there is no significant association between HCV, extrahepatic CCA, and papillary thyroid cancer.