Association between Non-Alcoholic Steatohepatitis-Related Hepatocellular Carcinoma and Periodontopathic Bacteria: A Cross-Sectional Pilot Study

The incidence of non-alcoholic steatohepatitis (NASH)-related hepatocellular carcinoma (HCC) is increasing annually as the metabolic syndrome factors increase. This study aimed to analyze the involvement of periodontopathic bacteria in NASH-related HCC (NASH-HCC). Questionnaire investigation, periodontal examination, medical examination, and specimen collection (saliva, mouth-rinsed water, and peripheral blood) were performed in 40 patients with NASH and in 20 patients with NASH-HCC. Immunoglobulin (Ig) G antibody titers against Porphyromonas gingivalis (p = 0.031) and Fusobacterium nucleatum (p = 0.003) were significantly higher in the NASH-HCC group than in the NASH group. P. gingivalis and F. nucleatum ratios were higher in the NASH-HCC group than in the NASH group; however, only F. nucleatum ratio was significant (p = 0.009). The Shannon index of salivary bacterial flora was significantly lower in the NASH-HCC group than in the NASH group (p < 0.001). The NASH-HCC group had a significantly lower salivary IgA concentration (p = 0.007) and a slower salivary IgA flow rate (p = 0.003). In all participants, the salivary IgA flow rate and the F. nucleatum ratio showed a significant negative correlation (p = 0.02). Oral P. gingivalis and F. nucleatum were possibly associated with NASH-HCC pathogenesis, and salivary IgA levels were correlated with F. nucleatum.