Hepatocellular carcinoma based on cryptogenic liver disease: The most common non-viral hepatocellular carcinoma in patients aged over 80 years.

Aim: To clarify the clinical features of patients with hepatocellular carcinoma (HCC) with cryptogenic liver diseases, we analyzed the data from a nationwide survey in Japan.

Methods: The survey was conducted in 2009. The factors examined included age and underlying liver diseases: alcoholic liver disease (ALD; n = 991), non-alcoholic fatty liver disease (n = 292), modest alcohol intake (intake between 20 and 70 g/day, n = 214) and cryptogenic liver diseases (n = 316). We compared the clinical features of cryptogenic HCC among patient-age subgroups.

Results: HCC with ALD etiology was most common among the non-viral HCC patients under 80 years old; for those aged 80 years or older, cryptogenic HCC was the most common etiology. Among the cryptogenic HCC patients, the body mass index values and the prevalences of liver cirrhosis (LC) and diabetes mellitus (DM) were significantly lower in the 80 years or older group versus the 50-79 years group. In the 80 years or older group, 28% of the patients developed HCC without cirrhosis, obesity and DM.

Conclusion: In the HCC patients aged 80 years and over, the etiology of most of the non-viral HCC cases was classified as cryptogenic. In light of our finding that the prevalences of obesity, DM and LC in the 80 years or older group of cryptogenic HCC patients were significantly lower those in the younger patients, it is apparent that analyses of HCC cases must take age differences into account.