Hepatitis B core‐related antigen levels after HBeAg seroconversion is associated with the development of hepatocellular carcinoma

Hepatitis B core‐related antigen (HBcrAg) is a novel serological marker for hepatitis B virus infection. Its clinical significance after HBeAg seroconversion has not been defined. We aimed to determine the relationship between HBcrAg levels after spontaneous HBeAg seroconversion and hepatocellular carcinoma (HCC). A total of 207 chronic hepatitis B patients with documented time of HBeAg seroconversion were enrolled. HBcrAg and HBsAg were checked within 3 years (as baseline), at 5 and 10 years after HBeAg seroconversion. HBV DNA was measured at the baseline. Multivariate Cox regression model was used to investigate the predictors for HCC development. The median follow‐up time was 13.1 (11.8‐15.5) years. Fourteen patients developed HCC (15‐year cumulative incidence: 7%). The median level of HBcrAg at baseline was significantly higher in patients who developed HCC when compared with patients without HCC (5.68 vs 4.78 log U/ml, respectively; P = .003). Cox proportional hazards model indicated that age of HBeAg seroconversion older than 40 years (hazard ratio (HR): 4.60; P = .049), presence of baseline cirrhosis (HR: 6.23; P = .003) and a higher baseline HBcrAg (HR: 1.75; P = .032) were independently associated with HCC development. A cut‐off value of baseline HBcrAg level ≥5.21 log U/mL yielded an AUROC of 0.74 with a negative predictive value of 97.7%. High HBcrAg levels within 3 years after HBeAg seroconversion were independently associated with the development of HCC in chronic hepatitis B patients.