Change in γ-glutamyl transpeptidase activity as a useful tool in identifying a group of patients with elevated risk of hepatocellular carcinoma development after DAA treatment of chronic hepatitis C

Aim of the study
Hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) incidence will be diminishing due to use of direct acting antiviral agents (DAA), but there is still constant risk for HCC development. Elevated serum γ-glutamyl transpeptidase (GGT) activity is associated with increased risk of liver cancer. In our study we tried to determine whether change in GGT activity may be useful in identifying patients with elevated risk of HCC development after DAA treatment.

Material and methods
The study population consisted of 111 patients with chronic hepatitis C (CHC) treated with DAA. Laboratory tests [alanine aminotransferase (ALT), GGT, a-fetoprotein (AFP)] and liver stiffness measurement (using FibroScan) were performed at the beginning and at the end of therapy.

Results
Pre-treatment ALT activity, GGT activity and AFP concentration in patients with CHC were directly associated with the stage of liver fibrosis. Elimination of HCV after DAA treatment caused significant reduction in serum GGT activity and was not associated with pre-treatment liver fibrosis. AFP concentration was significantly lower after treatment. It was observed regardless of pre-treatment AFP concentration, but the largest reduction was demonstrated in the group of patients with advanced fibrosis. In multivariate analysis there was no significant difference in GGT activity after treatment only in patients with pre-treatment normal AFP concentration and advanced liver fibrosis.

Conclusions
Patients who after achieving a sustained virological response (SVR) did not lower both AFP concentration and GGT activity may have higher risk of HCC development. Special monitoring may be required in patients with advanced liver fibrosis and normal AFP concentration before treatment.