Published in Clinical Gastroenterology and Hepatology, the research team performed a meta-analysis of articles published from 1996 through September 2012, ultimately studying 16 high-quality studies and a total of 3,153 cases.
The results of the analysis suggest that the risk of HCC is reduced by 40% for any coffee consumption vs no consumption, while some data indicated that consumption of three cups of coffee per day may reduce liver cancer risk by more than 50%.
"Our research confirms past claims that coffee is good for your health, and particularly the liver," said Dr Carlo La Vecchia from the Università degli Studi di Milan, Italy - lead author of the study.
"The favourable effect of coffee on liver cancer might be mediated by coffee's proven prevention of diabetes, a known risk factor for the disease, or for its beneficial effects on cirrhosis and liver enzymes," he suggested.
The Italian researchers said that despite the consistency of results across studies, time periods and populations, it is difficult to establish whether the association between coffee drinking and HCC is causal, or if this relationship may be partially attributable to the fact that patients with liver and digestive diseases often voluntarily reduce their coffee intake.
"It remains unclear whether coffee drinking has an additional role in liver cancer prevention," added Dr La Vecchia. "But, in any case, such a role would be limited as compared to what is achievable through the current measures."
La Vecchia and his colleagues said that their findings fill an important gap as the last meta-analysis was published in 2007, and since then there has been data published on more than 900 cases of HCC.
The team identified 16 high-quality studies published from 1996 through September 2012 - with pooled data for a total of 3,153 cases of HCC.
"The pooled estimate from the 6 studies published after 2007 was comparable with that of previous ones," said the researchers. "Thus, recent studies add up to the evidence that coffee drinkers have a 40% reduced risk of HCC compared with non-drinkers, and high drinkers have a more than 50% risk reduction."
The inverse relationship between coffee and HCC risk was consistent regardless of the subjects’ sex, alcohol drinking, or history of hepatitis or liver disease, they confirmed.
Source: Clinical Gastroenterology and Hepatology
Volume 11, Issue 11 , Pages 1413–1421.e1, doi: 10.1016/j.cgh.2013.04.039
"Coffee Reduces Risk for Hepatocellular Carcinoma: An Updated Meta-analysis"
Authors: Francesca Bravi, Cristina Bosetti, Alessandra Tavani, Silvano Gallus, Carlo La Vecchia