Cancer in Africa: opportunities for collaborative research and training.

Cancer is a worldwide public health problem causing increasing morbidity and mortality, particularly in the developing world. Underlying trends are changing the pattern of cancer and this is also being influenced by the HIV/AIDS pandemic, particularly in Sub-Saharan Africa. Even though the pattern of cancer varies across Africa, there are identifiable trends. Breast and cervical cancers, and Kaposi sarcoma are the commonest cancers in women, while Kaposi sarcoma, liver and prostate cancers are the commonest in men. Cancer causes more morbidity and mortality in Africa compared to other parts of the world. Infections account for a disproportionate amount of cancers in Africa. The HIV epidemic is contributing to increased prevalence of many cancers particularly those associated with Herpes and Papilloma viruses. Tobacco use, another major carcinogen, is increasing, particularly among the young. Dietary factors, alcohol use, physical inactivity and environmental pollution are also important aetiological factors of cancer in Africa. In developing countries, poverty, limited government health budget and poor health care systems complicate cancer prevention, treatment and outcomes. Coordinated response by international agencies and NGOs is needed to help developing countries and several successful models exist. More action is also needed on ensuring safety and quality of chemotherapy and the price needs to be reduced. Responses advocated for cancer control in Africa include banning tobacco use, better regulation of alcohol sale, better environmental planning and immunization against cancer associated viruses. Training of health care workers to diagnose cancer and treat it effectively within limited budgets is needed. Research to develop these new treatments and others, particularly from natural products is urgently needed and this can be done safely within established health research ethics regulatory frameworks. Several opportunities for collaborative research and training include an update of the epidemiology of cancers in African females; the relationship between HIV and other carcinogenic viruses; biological factors making cancers in Africa more lethal; cheaper vaccines that will be more available and easier to store and hence can be included in the immunization programme in African countries and development of vaccines like the HPV against other uncommon serotypes of the virus.