Abstract 3594: Impact of metformin on HCC prognosis

Abstract

Abstract Concurrent with the increase in hepatocellular carcinoma (HCC) incidence, the prevalence of metabolic syndrome has increased in the USA. Metabolic syndrome is currently considered a major health problem. Moreover, long term diabetes mellitus is an independent risk factor for HCC. We have previously shown that use of metformin among diabetics was associated with 70% risk reduction of HCC as compare to the use of other types of antidiabetic treatment. It is not known, however, if diabetic patients with HCC who used metformin had a better prognosis. Between 2001 and 2010 we interviewed 438 patients with pathologically confirmed HCC for multiple risk factors of HCC including prior history of diabetes and type of antidiabetic treatment. Survival times were calculated from the date of pathology diagnosis and were censored for patients who were alive at the last follow up. Median survival was calculated using Kaplan Meier product-limit method and survival rates were compared using the log rank test. Cox proportional hazards model (CPHM) was used to estimate the multivariate Hazard Risk Ratios (HRR) and 95% Confidence Interval (CI). Total of 130 HCC patients (29.7%) recalled prior history of diabetes with more than 1 year prior to HCC diagnosis. Most subjects were considered to have type 2 diabetes mellitus and were on an oral antidiabetic regimen. The survival duration for HCC patients with diabetes did not significantly differs from those without diabetes in men and women. However, HCC diabetic men who received metformin had a better survival outcome. The median survival was 14.9 months (95% CI, 1.3-28.9) for metformin users compared to 12.7 months (95% CI. 6.2-10.1) among HCC diabetic men who received other treatments, Log Rank p value=.04. CPHM, which included age, hepatitis C virus infection, alcohol consumption, treatment of HCC (chemotherapy and surgical treatment), history of cirrhosis, and Liver Italian Program (CLIP) staging score yielded 40% improvement of overall survival in HCC men with diabetes who received metformin as compared to other treatments. The estimated HRR (95% CI) was 0.56 (.35-.91), P =.02. These results suggest a possible beneficial role of metformin in diabetic men with HCC. Such observations need to be confirmed in other populations and with correlation with duration of metformin intake. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3594. doi:1538-7445.AM2012-3594