Background and aims: diabetes has been reported as a risk factor for hepatocellular carcinoma (HCC) in population-based studies but there are controversial data in patients with cirrhosis. Metformin could have a protective role in HCC development. The aim of this study was to determine the influence of diabetes on the risk of developing HCC in patients with alcohol- and hepatitis C virus (HCV)-related cirrhosis.
Methods: a cohort of 982 Caucasian patients were analyzed with alcoholic or HCV cirrhosis, included from 1992 to 2014 in a HCC surveillance program and prospectively followed. The influence of diabetes on the development of HCC was analyzed by Kaplan Meier analysis and adjusted with a Cox regression for relevant co-factors.
Results: after a median follow-up of 49.5 (24.0-96.0) months, 156 patients (15.8 %) developed HCC. There were no differences in the cumulative incidences of HCC after 20 years between diabetic and non-diabetic patients in the global (53.5 % vs 45.4 %; p = 0.26), alcoholic (50.4 % vs 45.4 %; p = 0.21) or HCV (60 % vs 43.1 %; p = 0.57) cirrhosis series. Diabetes did not constitute a risk factor after adjusting for other potential co-factors, neither in the whole series (hazard ratio [HR]: 1.12, 95 % CI: 0.78-1.51; p = 0.26), alcoholic (HR: 1.160, 95 % CI: 0.74-1.82; p = 0.50) or HCV cirrhosis cohort (HR: 1.17, 95 % CI: 0.63-2.19; p = 0.60). These figures did not change after excluding patients treated with metformin.
Conclusions: in Caucasian patients with alcoholic or HCV cirrhosis, diabetes is not a risk factor for developing HCC. This lack of an association does not seem to be a consequence of the protective effect of metformin.