In the treatment of chronic hepatitis B (CHB), the ultimate goal is preventing hepatitis B virus (HBV)-associated liver disease, including hepatocellular carcinoma (HCC). Recently published studies show that in CHB patients treated with the currently recommended first-line nucleos(t)ide analogs (NAs) entecavir or tenofovir, annual HCC incidences range from 0.01% to 1.4% in non-cirrhotic patients, and from 0.9% to 5.4% in those with cirrhosis. In Asian studies including matched untreated controls, current NA therapy consistently resulted in a significantly lower HCC incidence in patients with cirrhosis, amounting to an overall HCC risk reduction of ∼30%; in non-cirrhotic patients, HCC risk reduction was overall ∼80%, but this was only observed in some studies. For patients of Caucasian origin, no appropriate comparative studies are available to date to evaluate the impact of NA treatment on HCC. Achievement of a virologic response under current NA therapy was associated with a lower HCC risk in Asian, but not Caucasian studies. Studies comparing entecavir or tenofovir with older NAs generally found no difference in HCC risk reduction between agents, except for one study which used no rescue therapy in patients developing lamivudine resistance. Overall, these data indicate that with the current, potent NAs, HCC risk can be reduced but not eliminated, probably due to risk factors that are not amenable to change by antiviral therapy, or events that may have taken place before treatment initiation. Validated pre- and on-therapy HCC risk calculators that inform the best practice for HCC surveillance and facilitate patient counseling would be of great practical value.

Chronic hepatitis B patients are at increased risk for hepatocellular carcinoma (HCC). The effect of medium-term nucleos(t)ide analogue therapy on HCC incidence is unclear; therefore, we systematically reviewed all the data on HCC incidence from studies in chronic hepatitis B patients treated with nucleos(t)ide analogues. We performed a literature search to identify studies with chronic hepatitis B patients treated with nucleos(t)ide analogues for> or = 24 months. Twenty-one studies including 3881 treated and 534 untreated patients met our inclusion criteria. HCC was diagnosed in 2.8% and 6.4% of treated and untreated patients, respectively, during a 46 (32-108) month period (p=0.003), in 10.8% and 0.5% of nucleos(t)ide naive patients with and without cirrhosis (p<0.001) and in 17.6% and 0% of lamivudine resistance patients with and without cirrhosis (p<0.001). HCC developed less frequently in nucleos(t)ide naive patients compared to those without virological remission (2.3% vs 7.5%, p<0.001), but there was no difference between lamivudine resistance patients with or without virological response to rescue therapy (5.9% vs 8.8%, p=0.466). Chronic hepatitis B patients receiving medium-term nucleos(t)ide analogue therapy had a significantly lower incidence of HCC compared to untreated patients but treatment does not completely eliminate the risk of HCC. Among the treated patients, cirrhosis, HBeAg negative at baseline and failure to remain in virological remission were associated with an increased risk of HCC.

Hepatitis B virus (HBV) causes chronic infection in more than 350 million people worldwide. It replicates in hepatocytes but is non-cytopathic; liver damage is thought to be immune mediated. Here, we investigated the role of innate immune responses in mediating liver damage in patients with chronic HBV infection. Longitudinal analysis revealed a temporal correlation between flares of liver inflammation and fluctuations in interleukin (IL)-8, interferon (IFN)-α, and natural killer (NK) cell expression of tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) directly ex vivo. A cross-sectional study confirmed these findings in patients with HBV-related liver inflammation compared with healthy carriers. Activated, TRAIL-expressing NK cells were further enriched in the liver of patients with chronic HBV infection, while their hepatocytes expressed increased levels of a TRAIL death–inducing receptor. IFN-α concentrations found in patients were capable of activating NK cells to induce TRAIL-mediated hepatocyte apoptosis in vitro. The pathogenic potential of this pathway could be further enhanced by the ability of the IFN-α/IL-8 combination to dysregulate the balance of death-inducing and regulatory TRAIL receptors expressed on hepatocytes. We conclude that NK cells may contribute to liver inflammation by TRAIL-mediated death of hepatocytes and demonstrate that this non-antigen–specific mechanism can be switched on by cytokines produced during active HBV infection.