The journey from hepatitis to hepatocellular carcinoma - Bridging role of Helicobacter species

Hepatocellular carcinoma (HCC) is a long-term consequence of chronic liver disease, whose aetiology could result from viral, environmental and heredit ary causes. Viral infection, by itself, could only partially explain the pa thogenesis of cirrhosis and HCC. A new aetiologic agent capable of inducing chronic active hepatitis and hepatocellular tumours was discovered: it is a bacterium belonging to the genus Helicobacter, and named H. hepaticus. Pr esence of sequences belonging to the 16S rRNA of Helicobacter species (spp. ) has been demonstrated in liver of most patients with cirrhosis and HCC. H . pylori and related bacteria, such as H. hepaticus, produce toxins that ki ll hepatocyte by a granulating effect on liver cell lines. In vivo, such to xins might reach the liver through the portal tract, thereby causing hepato cellular damage. The recognition of Helicobacter spp. as a possible risk fa ctor for cirrhosis and HCC might have a practical impact on the general pop ulation: the treatment of this infection is easy and far less expensive tha n liver transplantation or any long term treatment for the other risk facto rs of HCC. Any confirmation of the involvement of Helicobacter in liver dis ease would eventually come from the success of culturing the bacterium from liver tissues. Future research is needed to clarify the importance of Heli cobacter spp. in respect to the other pathogens already known as causative agents of chronic inflammation of the liver and its long term sequelae, nam ely cirrhosis and HCC.