 A prospective, hospital-based study enrolling 40 chronic hepatitis C patients concomitant with malignancy other than hepatocellular carcinoma and other sex- and age-matched 80 chronic hepatitis C patients without malignancy will be conducted. The 40 chronic hepatitis C patients concomitant with malignancy other than hepatocellular carcinoma will receive pegylated interferon-alpha 2a plus ribavirin combination therapy at remission phase after oncological treatments andor interventions. The other 80 chronic hepatitis C patients without malignancy receiving the same antiviral therapy will serve as controls. The primary outcome measurement is sustained virological response and safety, whilst the secondary measurement is rapid virological and early virological response. 