ACCUMULATING evidence that liver cancer may be related to the early stages of non-alcoholic fatty liver disease (NAFLD) is one more reason to tackle the burgeoning epidemic of obese people, according to an Australian expert.
Professor Jacob George, director of the Storr Liver Unit at the Westmead Millennium Institute in Sydney, said it was estimated that in future NAFLD would be the cause of 30% of hepatocellular carcinoma (HCC) rather than less than 5% as it was now.
“People now have metabolic syndrome even in youth or teenage [years] and so end-stage NAFLD-related liver disease is being seen in people in their 40s, which is a worry,” Professor George said.
He said NAFLD-related liver failure would be the commonest cause of liver transplantation in the US by 2020.
“What we now recommend is that those with NAFLD should be referred to hepatologists for an assessment of their liver status, especially if they are over 50 years old, have poorly controlled diabetes or have multiple components of metabolic syndrome,” he said.
Professor George was commenting on an article in Gut, which said that the rapidly increasing prevalence of obesity and diabetes in affluent societies, and their significance in the pathophysiology of NAFLD, would result in a rising incidence of NAFLD and its complications — including HCC — in the mid-term future.(1)
NAFLD is now the most common cause of raised liver enzyme levels in Western countries.
The authors said it meant dietary recommendations or tight diabetic control should not only be for patients with “pure” NAFLD but also for those with other liver disease and metabolic syndrome.
They said that based on the known association of NAFLD with insulin resistance and metabolic syndrome, one study had looked at patients with HCC and NAFLD and found about two-thirds of the patients were obese and/or diabetic and a remarkable 25% had no cirrhosis.
Professor George said screening for HCC was only cost-effective when the risk in a cohort was more than 1%–1.5% per year. While this was the case for hepatitis C and hepatitis B with cirrhosis, the risk of HCC with NAFLD was still very low.
“In practice, what people do is screen NASH [non-alcoholic steatohepatitis] and NAFLD cirrhotics for HCC,” he said.
Professor John Olynyk, professor of hepatology at the University of Western Australia, said the increasing evidence of an association with HCC and early stage NAFLD was another reason to not get fat and focus on preventing obesity in children.
Only patients with established significant fibrosis or cirrhosis should be considered for screening for liver cancer, Professor Olynyk said.
“Current recommendations for high-risk screening for HCC include 6-monthly ultrasound and alpha-fetoprotein measurement.”
Professor Olynyk said modifiable risk factors should be addressed, including weight reduction and exercise for NAFLD and NASH, treatment of viral hepatitis, reduction of alcohol, improvement in nutrition and treatment of hereditary haemochromatosis.
Posted 27 September 2010