Sample selection~Select communities of 70,000 to 120,000 populations in Zhongshan City as the investigators' fields.~Divide them into screening group and control group according to the areas of administration~Participants recruitment~- Subjects voluntarily attend this screening study~Informed consent - Informed consent forms will be collected at the recruitment.~Questionnaires~- Face-to-face interviews are conducted by well-trained investigators~Serological tests~Each blood samples will be tested for the surface antigen of the hepatitis B virus (HBsAg).~Among those who are positive for HBsAg, further clinical work-ups including Alpha-Fetoprotein(AFP) test and ultrasonography for liver exam will be performed and high risk group will be selected according to the definition.~HCC diagnosis will be determined according to imaging and/or biopsy result.~The rest of the blood samples will be stored at the biobank of Zhongshan People's Hospital.~Follow up~The cohort will follow up according to the screening protocol. Briefly, Repeated check-ups will be performed in 6-months among HBsAg positive group and 3-years among HBsAg negative group.~All subjects in the control arm (control communities) will be followed by record linkage to Cancer Register and Population Register.
All participants in the selected communities will be tested for HBsAg by using serum samples. Among those who are positive for HBsAg, further clinical work-ups including AFP test and ultrasonography for liver exam will be performed. High risk group will be selected according to the definition. HCC diagnosis will be determined according to imaging and/or biopsy result. Repeated check-ups will be performed in 6-months among HBsAg positive group and 3-years among HBsAg negative group.~All subjects in the control arm (control communities) will be followed by record linkage to Cancer Register and Population Register.