Metformin and statins reduce hepatocellular carcinoma risk in chronic hepatitis C patients with failed antiviral therapy.

BACKGROUNDS AND AIM: Chronic hepatitis C (CHC) patients who fail antiviral therapy have a high risk of developing hepatocellular carcinoma (HCC). We investigated the effects of metformin and statins, commonly used to treat diabetes mellitus (DM) and hyperlipidemia (HLP), on HCC risk in CHC patients who failed antiviral therapy.

METHODS: CHC patients with failed interferon-based therapy were enrolled in a large-scale multicenter cohort study in Taiwan (T-COACH). HCC occurrence 1.5 years after the end of antiviral therapy was identified by linking to the cancer registry databases from 2003 to 2019. After considering death and liver transplantation as competing risks, Gray's cumulative incidence and Cox sub-distribution hazards for HCC development were used.

RESULTS: Among the 2,779 CHC patients, 480 (17.3%) developed new-onset HCC and 238 (8.6%) died after antiviral therapy. Metformin non-users with DM had a 51% higher risk of liver cancer than patients without DM, while statin users with HLP had a 50% lower risk of liver cancer than patients without HLP. The 5-year cumulative incidence of HCC was 16.5% in metformin non-users, significantly higher in metformin non-users than in patients without DM (11.3%; adjusted sub-distribution hazard ratio [aSHR]=1.51; P=0.007) and metformin users (3.1%; aSHR=1.59; P=0.022). Conversely, HLP statin users had a significantly lower HCC risk than patients without HLP (3.8% vs. 12.5%; aSHR=0.50; P<0.001). Notably, the unfavorable effect of non-metformin use on increased HCC risk was mainly observed among patients without cirrhosis but not in patients with cirrhosis. In contrast, a favorable effect of statins reduced the risk of HCC in both cirrhotic and non-cirrhotic patients.

CONCLUSION: Metformin for DM and statins for HLP have chemopreventive effects on HCC risk in CHC patients who failed antiviral therapy. These findings emphasize the importance of personalized preventive strategies for managing patients with these clinical profiles.