We thank Dr. Lo for his interest and comments about our study and would like to take this opportunity to make our article more accurately understood. First, this study adopts a retrospective cohort, instead of a case-control design, in that the subjects were grouped according to the exposure, rather than the outcome. For the purpose of optimizing comparability, we explicitly matched the treated and untreated cohorts in age, gender, cirrhosis, and postoperative treatment-free duration with a 1:4 proportion. In fact, the two groups did not significantly differ in their baseline characteristics, including age, diabetes mellitus (DM), and extent of resection. The eligibility and matching criteria as well as the flowchart of enrollment were all clearly described in our article in accord with the STROBE guidelines.
Second, the association between antiviral therapy and recurrent hepatocellular carcinoma (HCC) was verified in the multivariate-adjusted Cox proportional hazard model, which took various potential confounders into account. Moreover, this association appeared to be modified by age, DM, and cirrhosis, which were uncovered by the multivariate stratified analyses. Of note, factors that might modify the association should not be misinterpreted as independent predictors of HCC recurrence among the study participants. Besides, there is no reason to believe that these factors had confounded the result, because they were similarly distributed between groups and were well adjusted for in the Cox analysis.
Finally, this study does not intend to claim that postoperative institution of pegylated interferon plus ribavirin can effectively prevent most of the hepatitis C virus (HCV)-related HCCs from recurrence. In light of a cumulative incidence reaching 52.1% (95% confidence interval: 42.0-62.2) 5 years after postoperative antiviral therapy, it is clear that the risk of recurrent HCC was attenuated, but certainly not eliminated, in the treated patients. However, given that this regimen is reasonably safe and generally tolerable among patients able to recover from liver resection, our research does implicate a readily available way to improve the clinical outcomes. It is eagerly hoped that next generations of anti-HCV therapy will be more effective in decreasing recurrence of HCC, but proof is required and further research warranted.
Yao-Chun Hsu, M.D1,2
Chun-Ying Wu, M.D., MPH., Ph.D.1,3,4
1Graduate Institute of Clinical Medicine China Medical University Taichung, Taiwan
2Department of Internal Medicine E-Da Hospital/I-Shou University Kaohsiung, Taiwan
3Faculty of Medicine School of Medicine National Yang-Ming University Taipei, Taiwan
4Division of Gastroenterology Taichung Veterans General Hospital Taichung, Taiwan