Cancer in the developing world: how should care be delivered and research conducted?

Second of a two-part series. The development of specific types of cancer within individuals and populations is in large measure a reflection of lifestyle factors and exposures to carcinogens and infectious agents. These factors differ between regions— for example, infectious diseases cause far more cancers in developing countries than in developed countries—and change over time. " The tobacco epidemic started in Western countries and is now spreading worldwide, particularly to Asia, " noted Paul Kleihues, M.D., director of the International Agency for Research on Cancer (IARC) in Lyon, France. " The Western lifestyle, which is responsible for several major tumor types, including breast, prostate, colon, and en-dometrium cancer, is also increasingly acquired by developing countries. While the overall mortality from cancer is now declining in North America and some European countries, a steep increase can be predicted for many other regions. " As the picture of cancer incidence on the world map changes, and with a growing cancer burden expected to befall resource-poor nations, many experts believe cancer research should move toward globalization. Affluent nations, for which cancer has long been a feared and burdensome disease, continue to invest heavily in cancer research, and there have been tangible returns on the investment. But how can cancer research be exported to the developing world? " One cannot assume that all advances made in affluent nations can be applied without further testing to developing countries, " said Ian Magrath, M.D., president and medical and scientific director of the International Network for Cancer Treatment and Research in Brussels, Belgium. " The cancers may be biologically different—the people and their co-morbidities certainly are—and facilities, including supportive care, differ quite dramatically. What works in New York may not be ideal for Dar es Salaam. " Prevention and Screening There are some interventions that could be readily used in resource-poor nations. " From a public health point of view, there is already a sound basis of knowledge about preventive strategies, and there is plenty of opportunity for operational research into how they can be applied, " said Max Parkin, M.D., chief of IARC's Unit of Descriptive Epidemiology. For example, Parkin is working on the Gambian Hepatitis Intervention Study, unusual for its application of a primary preventive strategy in a high-risk, low-resource population. It is one of two randomized studies evaluating the efficacy of the hepatitis B virus (HBV) vaccine in preventing invasive cancer. The vaccine (which …