Background
China and the United States (US) ranked first and third in terms of new liver cancer cases and deaths globally in 2020. Therefore, a comprehensive assessment of trends in the incidence of primary liver cancer with four major etiological factors between China and the US during the past 30 years with age-period-cohort (APC) analyses is warranted.Methods
Data were obtained from the Global Burden of Disease 2019, and period/cohort relative risks were estimated by APC modeling from 1990 to 2019.Results
In 2019, there were 211,000 new liver cancer cases in China and 28,000 in the US, accounting for 39.4% and 5.2% of global liver cancer cases, respectively. For China, the age-standardized incidence rate (ASIR) consecutively decreased before 2005 but increased slightly since then, whereas the ASIR continuously increased in the US. Among the four etiological factors of liver cancer, the fastest reduction in incidence was observed in hepatitis B virus-related liver cancer among Chinese women, and the fastest increase was in nonalcoholic steatosis hepatitis (NASH)-related liver cancer among American men. The greatest reduction in the incidence of liver cancer was observed at the age of 53 years in Chinese men (-5.2%/year) and 33 years in Chinese women (-6.6%/year), while it peaked at 58 years old in both American men and women (4.5%/year vs . 2.8%/year). Furthermore, the period risks of alcohol- and NASH-related liver cancer among Chinese men have been elevated since 2013. Simultaneously, leveled- off period risks were observed in hepatitis C viral-related liver cancer in both American men and women.Conclusions
Currently, both viral and lifestyle factors have been and will continue to play an important role in the time trends of liver cancer in both countries. More tailored and efficient preventive strategies should be designed to target both viral and lifestyle factors to prevent and control liver cancer.