Influence of Interferon-free Direct-acting Antiviral Therapy on Primary Hepatocellular Carcinoma Recurrence: A Landmark Time Analysis and Time-dependent Extended Cox Proportional Hazards Model Analysis.

Objective The influence of interferon (IFN)-free direct-acting antiviral (DAA) on hepatocellular carcinoma (HCC) recurrence remains unclear. Previous retrospective analyses revealed that the time interval between HCC curative treatment and IFN-free DAA induction is the critical factor affecting HCC recurrence. Thus, this study aimed to examine the influence of DAA therapy on HCC recurrence considering this interval. Methods Factors contributing to HCC recurrence were retrospectively analyzed using a landmark time analysis and time-dependent extended Cox proportional hazards model. Patients After screening 620 patients who were diagnosed with primary HCC from January 2001 to December 2016, 76 patients with early-stage (primary and solitary) disease who received curative treatment and were positive for serum hepatitis C virus RNA were included. Results HCC recurrence was observed in 8 of 17 (47.1%) patients who had received IFN-free DAA therapy and 45 of 59 (76.3%) who had not. No significant difference was seen between the IFN-free DAA (-) and IFN-free DAA (+) groups in the landmark time and time-dependent Cox proportional hazards model analyses. However, IFN-free DAA therapy tended to decrease the HCC recurrence rate after curative treatment for primary HCC in patients with chronic hepatitis. In addition, IFN-free DAA therapy tended to decrease the second HCC recurrence rate after treatment for the first HCC recurrence. Conclusion Our results, with a consideration of the time interval between HCC curative treatment and IFN-free DAA induction, showed that IFN-free DAA therapy was not associated with early-stage HCC recurrence after curative treatment.