A polymorphism in interferon L3 is an independent risk factor for development of hepatocellular carcinoma after treatment of hepatitis C virus infection

Background & aims: Polymorphisms in interferon (IFN)L3 (encodes IFNλ3 or interleukin 28B) are associated with outcomes of treatment for hepatitis C virus (HCV) infection. However, there is controversy regarding how polymorphisms in IFNL3 affect the risk for development of hepatocellular carcinoma (HCC) in patients treated with pegylated interferon and ribavirin.

Methods: In a retrospective study, we analyzed data from 1118 patients with HCV infection (589 men; median age, 60 y; 49.9% infected with genotype 1; 51.3% with advanced fibrosis) treated with pegylated interferon and ribavirin from March 2000 through October 2009 at the Chang Gung Memorial Hospital in Kaohsiung, Taiwan (71.64% achieved sustained virologic response [SVR]). Baseline samples were collected before therapy. Starting 24 weeks after treatment, clinical and biochemical features were assessed every 3 to 6 months and patients underwent ultrasound examinations. Lesions detected were examined by computed tomography, angiography, or fine-needle aspiration biopsy analyses. Patients were followed up from the initiation of HCV therapy until a diagnosis of HCC (based on published guidelines), death, or March 31, 2013 (median, 60 mo). DNA samples from each patient were analyzed for rs12979860 in IFNL3. Kaplan-Meier analysis was used to determine the risk for development of HCC.

Results: The percentages of patients with the IFNL3 rs12979860 CC, CT, and TT genotypes were 86.4%, 13.2%, and 0.3%, respectively. A total of 108 patients (9.66%) developed HCC. The IFNL3 rs12979860 CT and TT genotypes correlated with high baseline levels of α-fetoprotein (AFP; ≥20 ng/mL), advanced stage of fibrosis, diabetes, or lack of an SVR (all P < .05). Based on multivariate Cox regression analysis, age 60 years and older, low platelet count (<15 × 10(9) cells/L), AFP level of 20 ng/mL or greater, advanced stage fibrosis, diabetes, lack of an SVR, and the IFNL3 rs12979860 CT and TT genotypes were significant risk factors for HCC (P < .05). Age 60 years and older, low numbers of platelets or high AFP level, and advanced fibrosis were risk factors for HCC among patients with a SVR. The IFNL3 rs12979860 genotype did not have a significant effect on risk for HCC among patients with SVRs, although some of these patients (with the CT or TT genotype) did develop HCC. Among patients without SVRs, only fibrosis stage and the IFNL3 rs12979860 CT and TT genotypes (hazard ratio, 1.80; 95% confidence interval, 1.06-3.07; P = .030) were independent risk factors for HCC.

Conclusions: Based on a retrospective study of patients treated for HCV infection, the IFNL3 rs12979860 CT and TT polymorphisms are associated with a risk for HCC, especially in patients without a SVR.