Background and aim: This study was designed to determine whether non-alcoholic fatty liver disease (NAFLD), with or without metabolic syndrome (MetS), is a risk factor for cancer development.
Methods: We conducted a retrospective longitudinal study at the Center for Preventive Medicine, St. Luke's International Hospital. Among all participants who underwent a health checkup between 2005 and 2019, cancer development tendencies were compared between those who were diagnosed with NAFLD and those who were not. Further evaluation was conducted among NAFLD-diagnosed participants with versus without MetS in the same manner. Those with a history of a specific liver disease, any type of cancer, or alcohol consumption in any amount at the time of the initial visit were excluded from the study.
Results: Data were collected from 30 172 participants who underwent health checkups, among whom 4394 (14.6%) had NAFLD. Over the 14-year follow-up period, 2086 participants (6.9%) developed cancer. Participants with NAFLD had a higher incidence of digestive organ neoplasms (odds ratio [OR]: 1.34, 95% confidence interval [CI]: 1.07-1.67), especially in the stomach (OR: 1.40, 95% CI: 1.02-1.94) and small intestine (OR: 2.80, 95% CI: 0.87-8.96), than did those without NAFLD. Participants with NAFLD and MetS had significantly lower rates of neoplasms in respiratory and intrathoracic organs (OR: 0.35 95% CI: 0.14-0.88) and male genital organs (OR: 0.46 95% CI: 0.24-0.87) than did individuals without NAFLD.
Conclusions: Non-alcoholic fatty liver disease is associated with the development of gastrointestinal malignancies, while MetS is a negative risk factor for lung and prostate cancer.
Keywords: Helicobacter pylori; International Statistical Classification of Diseases; dysbiosis; insulin resistance; metabolic syndrome; neoplasm; non-alcoholic fatty liver disease; small intestinal bacterial overgrowth.
© 2020 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.