BACKGROUND: There is no information available about occult hepatitis B virus (HBV) infection (OBI) in individuals with intrahepatic cholangiocarcinoma (ICC). GOALS: To investigate the correlation between OBI and ICC. STUDY: A retrospective case-control study was conducted. The cases were 183 cryptogenic ICC patients (group I), and the controls were 549 healthy individuals (group II). The cases and controls were matched for age, sex, and inhabitancy. Adjusted odds ratios and 95% confidence intervals were calculated. Intrahepatic total HBV DNA in 63 paraffin-embedded samples was collected from patients in group I (n=44), HBV-associated ICC patients (n=3), and hepatic cavernous hemangioma patients with seronegative HBsAg (hepatitis B S antigen) (group III; n=16). We determined the levels of serum and intrahepatic HBV DNA and compared the level of intrahepatic HBV DNA in 44 cryptogenic patients from group I with the level in the patients from group III. RESULTS: Compared with group II, group I had a lower prevalence of anti-HBs (antibody against HBsAg) and a higher prevalence of anti-HBe (antibody against hepatitis B e antigen) and anti-HBc (antibody against hepatitis B c antigen). Multivariate analysis confirmed that anti-HBe and anti-HBc positivity were associated with ICC. The odds ratios and 95% confidence intervals for anti-HBe and anti-HBc were 2.482 and 1.482-4.158, 4.556 and 2.938-7.066, respectively. Compared with group III, cryptogenic ICC cases showed more frequent detection of intrahepatic total HBV DNA (63.64% vs. 18.75%, P=0.002). CONCLUSIONS: OBI may represent an important risk factor for ICC. HBsAg seroclearance does not signify eradication of HBV and may not entirely prevent the development of ICC.
BACKGROUND: There is no information available about occult hepatitis B virus (HBV) infection (OBI) in individuals with intrahepatic cholangiocarcinoma (ICC). GOALS: To investigate the correlation between OBI and ICC. STUDY: A retrospective case-control study was conducted. The cases were 183 cryptogenic ICC patients (group I), and the controls were 549 healthy individuals (group II). The cases and controls were matched for age, sex, and inhabitancy. Adjusted odds ratios and 95% confidence intervals were calculated. Intrahepatic total HBV DNA in 63 paraffin-embedded samples was collected from patients in group I (n=44), HBV-associated ICC patients (n=3), and hepatic cavernous hemangiomapatients with seronegative HBsAg (hepatitis B S antigen) (group III; n=16). We determined the levels of serum and intrahepatic HBV DNA and compared the level of intrahepatic HBV DNA in 44 cryptogenic patients from group I with the level in the patients from group III. RESULTS: Compared with group II, group I had a lower prevalence of anti-HBs (antibody against HBsAg) and a higher prevalence of anti-HBe (antibody against hepatitis B e antigen) and anti-HBc (antibody against hepatitis B c antigen). Multivariate analysis confirmed that anti-HBe and anti-HBc positivity were associated with ICC. The odds ratios and 95% confidence intervals for anti-HBe and anti-HBc were 2.482 and 1.482-4.158, 4.556 and 2.938-7.066, respectively. Compared with group III, cryptogenic ICC cases showed more frequent detection of intrahepatic total HBV DNA (63.64% vs. 18.75%, P=0.002). CONCLUSIONS: OBI may represent an important risk factor for ICC. HBsAg seroclearance does not signify eradication of HBV and may not entirely prevent the development of ICC.