Antiviral Treatment Reduces Risk of Development of Lung Cancer and Non-Hodgkin Lymphoma in Patients with Chronic Hepatitis C.

backgroundAntiviral treatment for hepatitis C virus (HCV) has been shown to reduce risk of liver cancer, but there are few studies on its impact on the risk of non-liver cancers. We used a large cohort of patients with HCV with extensive follow-up to investigate whether receipt of antiviral therapy affects the risk of extrahepatic cancers.

methodsA total of 17,485 patients with HCV were followed until incidence of lung cancer, non-Hodgkin lymphoma (NHL), breast or prostate cancer, death, or last follow-up. We used multivariable modeling with time-varying covariates and propensity scores to adjust for treatment selection bias; we also applied generalized estimating equations with a multinominal link function for discrete time-to-event data. Death was considered a competing risk.

resultsAfter 15 years of follow-up, we identified 408 incident cases of cancers, namely 140 lung, 72 NHL, 81 breast (female), and 115 prostate cancer cases. Compared with no treatment, patients who receive either direct-acting antivirals or IFN-based treatment had significantly lower risk of lung cancer [HR = 0.35, 95% confidence interval, 0.24-0.52 for achieving sustained virologic response (SVR); HR = 0.34, 95% confidence interval, 0.21-0.55 for treatment failure]. Risk of NHL was reduced only among patients who achieved SVR. There were no significant associations between antiviral therapy and risks of breast and prostate cancers.

conclusionsAntiviral treatment for HCV independently reduced the risk of lung cancer, whereas the protective association with NHL was limited to patients achieving SVRs. IMPACT: Our findings support the importance of timely initiation antiviral therapy in patients with chronic HCV.