Epidemiology of hepatocellular carcinoma.

Because of its high incidence in many of the most populous countries in the world, its often fulminant course, poor response to conservative treatment, low resectabilty rate when symptomatic, high recurrence rate after resection and liver transplantation, and grave prognosis, hepatocellular carcinoma is now regarded as one of the major malignant diseases. Hepatocellular carcinoma is the most common primary malignant tumour of the liver. Relative to other tumours, it ranks fifth in overall frequency (fifth in men and eighth in women) and fourth in annual mortality rate. An estimated 372,000 new cases of hepatocellular carcinoma are diagnosed each year, constituting 4.6% of all new human cancers (6.3% in men; 2.7% in women). The annual mortality rate from the tumour is virtually the same as its annual incidence. The highest incidences occur in eastern and southeastern Asia, some of the Western Pacific islands, and sub-Saharan Africa. Intermediate incidences are found in eastern and southern Europe, the Caribbean, Central America, and Western Asia. Hepatocellular carcinoma is uncommon in the remaining countries. Men are affected more often than are women. The incidence generally increases with increasing age, although there is a definite shift towards a younger age distribution in black African and ethnic Chinese populations.