Liver cancer
Globally, , liver cancer resulted in 754,000 deaths, up from 460,000 in 1990, making it the third leading cause of cancer death after lung and stomach. In 2012, it represented 7% of cancer diagnoses in men, the 5th most diagnosed cancer that year. Of these deaths 340,000 were secondary to hepatitis B, 196,000 were secondary to hepatitis C, and 150,000 were secondary to alcohol. HCC, the most common form of liver cancer, shows a striking geographical distribution. China has 50% of HCC cases globally, and more than 80% of total cases occur in sub-Saharan Africa or in East-Asia due to hepatitis B virus. Cholangiocarcinoma also has a significant geographical distribution, with Thailand showing the highest rates worldwide due to the presence of liver fluke.
R. Palmer Beasley
Nonetheless, Beasley pursued his controversial hypothesis by designing one of the first large cohort studies to test the link between hepatitis B and liver cancer. With his co-investigator, Lu-Yu Hwang, and the Taiwan team of investigators, he conducted a study of over 22,000 government workers starting in 1974 and followed them up to the present. That long-term study found that the risk of liver cancer was 60 times higher in chronic HBV-infected persons than non-HBV carriers, and that the lifetime risk of dying from liver cancer was 40% in infected men and 15% in infected women. Noted that the association between liver cancer and HBV carriers was stronger than the association between lung cancer and smoking (i.e., 20–25 times). "It's one of the highest relative risks that anyone has ever seen," said Beasley. However, skepticism remained "because many people feel that establishing causation requires elucidating a plausible mechanism by which the effect occurs," he recalled.