In most developed nations, cancer is second only to heart disease as a cause of death; in less developed countries, it is second to infectious disease. It is estimated that if the current trends of rising worldwide incidence continue, cancer will become the leading cause of death in the 21st century. This is particularly troubling since many of the factors contributing to cancer (eg, occupation, diet, lifestyle, and tobacco use) are known.
The politics of science have had an enormous impact on the development of public policy programs for the prevention and treatment of many types of cancer. Highly politicized and well-financed interest groups include environmentalists, tobacco companies, labor unions, physicians, scientists, and patient advocates. They have the capacity to affect which diseases and therapies are and are not researched, evaluated, and treated, and which information is disseminated and by what means.
Balancing these often conflicting interests affects the success of large-scale initiatives. Despite these obstacles, broad education, prevention, and treatment measures must be considered, to establish control over the incidence and costs of cancer.
Excellent practical examples of highly organized and effective initiatives are the programs developed to eradicate hepatitis B virus infection and hepatocellular carcinoma. These programs have proven so successful that the World Health Organization considers hepatitis B vaccination the most important cancer prevention program today, with the exception of smoking cessation programs.
More than 75% of the world's chronic hepatitis B carriers live in the Asia-Pacific region. In countries with large economic resources and a significant hepatitis B problem, such as Malaysia, Singapore, and Taiwan, national immunization programs have reduced hepatitis B carrier rates from approximately 10% to 1%-2% in 3 to 5 years. In China, the seropositivity rate for HBsAg has been reduced from 16.3% to 1.4% since 1986. In Thailand and the Philippines, despite fewer resources, similar improvements have been noted.
However, in countries that are poor and involved in political turmoil, such as Myanmar, Indonesia, and Cambodia, programs have not been initiated because of a lack of political commitment and economic resources. Likewise, most African countries are unable to obtain funding for vaccination programs, despite political interest and even though it is estimated that vaccination would control more than 75% of hepatitis B cases in Africa.
In areas with a lower incidence, vaccination program development has been variable. New Zealand has been a pioneer in hepatitis B immunization, while Australia has not adopted any program.