A 33-year-old male immigrant from Taiwan presents with increasing right upper quadrant (RUQ) pain. The pain is dull, and it does not radiate or change with eating. On examination the abdomen is soft, there is a mass in the RUQ, and no ascites is clinically detected. He has a prior history of hepatitis B. His laboratory investigations reveal hepatitis B surface antigen (HBsAg) positive, hepatitis B surface antibody (HBsAb) negative, aspartate amino transferase (AST) 60 U/L, alanine amino transferase (ALT) 72 U/L, and an elevated alpha-fetoprotein level. Which of the following is the most likely diagnosis?

(b) Source: (Devita, pp. 533-534) Only the chronic carrier state increases HCC risk, not previous infection. The majority, but not all, of HCC associated with HBV occurs in the setting of cirrhosis (60-90%). Because the latency period of HBV infection is 35 years, before HCC supervenes, early-life infection is strongly correlated with HCC. The chronic carrier state of HBsAg in endemic areas, such as Taiwan, is associated with a relative risk of over 100 for the development of HCC. Over half the chronic carriers of HBsAg in such a population will die of cirrhosis or HCC. In Taiwan, where childhood vaccination was introduced in 1984, the death rate from childhood HCC has already declined.