Authors' response: Additional more factors should be included in predicting risk of hepatocellular carcinoma in patients with chronic hepatitis B virus infection.

We appreciate the letter from Yanqing et al1 , which raised several concerns about our study2 . First, we definitely agree that serum hepatitis B s antigen (HBsAg) is significantly associated with the risk of hepatocellular carcinoma (HCC) development, as proven in REAVAL-HBV and ERADICATE-B studies3 . In both studies, serum HBsAg and hepatitis B virus (HBV) DNA levels independently predicted the risk of HCC development. Particularly, serum HBsAg level was complementary to HBV DNA level in stratifying HCC risks in patients with HBV DNA levels < 200,000 IU/mL4 . Unfortunately, HBsAg was not covered by South Korea's national insurance program during our enrollment period. Therefore, for more accurate prognostication, the current risk prediction models for HBV-related HCC which were used in our study should be optimized according to the HBsAg level during ETV or TDF treatment in future studies.