Nucleos(t)ide analogs in the prevention of hepatitis B virus related hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is among the most common cancer types and causes of cancer related mortality worldwide. Almost 50% of all HCC cases globally are attributable to chronic hepatitis B virus (HBV) infection. The incidence rates of HCC in untreated Asian subjects with HBV infection was estimated to be 0.2% in inactive carriers, 0.6% for those with chronic hepatitis without cirrhosis, and 3.7% for those with compensated cirrhosis. In Western populations, HCC incidences are reported to be 0.02% in inactive carriers, 0.3% in subjects with chronic hepatitis without cirrhosis, and 2.2% in subjects with compensated cirrhosis. Despite effective antiviral treatment options which are able to transform chronic hepatitis into an inactive carrier state, the risk of HCC cannot be fully ruled out to exclude those patients from surveillance. Newer nucleos(t)ide analogues (NAs) as entecavir and tenofovir are very potent in terms of sustained virological suppression which leads to improved liver histology. However, they do not have any influence on the cccDNA or integrated DNA of HBV in the liver. Nonetheless, viral replication is the only modifiable component among the established risk factors for HBV-related HCC with the current treatment options. In this review, it was aimed to summarize cumulative evidence behind the concept of prevention of HBV related HCC by NAs, and to discuss remaining obstacles to eliminate the risk of HCC.