NAFLD linked with increased risk for extrahepatic cancers

Patients with non-alcoholic fatty liver disease had a moderately increased risk for extrahepatic cancers, such as gastrointestinal, breast and gynecological cancers, according to a meta-analysis.

Giovanni Targher, MD, from the University of Verona in Italy, and colleagues wrote that NAFLD is already recognized as a leading cause of hepatocellular carcinoma, but it is gaining interest for its link with other cancers as well.

“We believe that clarification of the magnitude of risk of developing some extrahepatic cancers among individuals with NAFLD will help refine the assessment of the true clinical and economic burden attributable to NAFLD,” they wrote. “These data will also help inform clinicians caring for patients with NAFLD and increase clinician awareness of the need for prevention and early diagnosis of certain types of extrahepatic cancers related to NAFLD.”

Investigators searched the literature for observational studies in which NAFLD was diagnosed. Their analysis included 10 cohort studies comprising 182,202 individuals.

In the overall group of patients, 24.8% had NAFLD, and researchers identified 8,485 incident cases of extrahepatic cancers over a median follow-up of 5.8 years.

Targher and colleagues found that NAFLD was associated with a 1.5-fold increased risk for developing GI cancers, including esophageal, stomach, pancreatic and colorectal cancers.

NAFLD was also associated with a 1.2- to 1.5-fold increased risk for developing lung, breast, gynecological or urinary system cancers.

All the risks were independent of age, sex, smoking status, obesity, diabetes and other confounders, and the findings did not change after sensitivity analysis.

“Further prospective and mechanistic studies are needed to decipher the existing but complex link between NAFLD and increased carcinogenesis.” Targher and colleagues wrote. “In particular, further research is needed to test the effects of NAFLD/obesity/diabetes, as it is possible that there could be interaction/additive effects or even synergism of NAFLD, obesity and diabetes to influence risk of certain extrahepatic cancers.”