We experienced two cases of hepatocellular carcinoma (HCC) occurring immediately after treatment with direct-acting antiviral agents (DAAs). Case 1 was a 75-year-old woman in whom HCC was detected immediately after completion of DAA treatment. Case 2 was a 75-year-old woman who had a hypovascular nodule in liver. The hypovascular nodule became hypervascular without enlargement of the nodule size immediately after DAA treatment completion. Although the association between DAA treatment and hepatocarcinogenesis is unknown, sufficient surveillance after achieving a sustained viral response is required, as a large number of patients at a high risk of hepatocarcinogenesis are treated with DAAs.
Keywords: direct-acting antiviral agents; hepatitis C virus; hepatocellular carcinoma; sustained virological response.