The burden of oral cancer in sub-Saharan Africa

Abstract

Objectives: To describe incidence and mortality rates of oral and of oropharyngeal cancers in sub-Saharan Africa using available sources and to discuss shortcomings. Methods: Incidence and mortality rates were obtained from GLOBOCAN online (IARC 2012) and the pathology-based South African National Cancer Registry (SA-NCR). Descriptions of oral and of oropharynx cancers for the four main geographical regions were derived from the literature. For South Africa, the incidence by ethnic group of lip and intra-oral cancer over the period 1988–2012 could be calculated from SA-NCR. The age distributions for intraoral and for oropharynx cancer in both genders in South Africa were compared for the period 1996–2002. Results: Age standardized incidence rates and mortality rates of lip and of oral cancer in sub-Saharan Africa varied substantially, depending on the regions, the mix of carcinogenic substances consumed in each country and the quality of the cancer registry data. African islands in the Indian Ocean and the Southern and Eastern African countries report the highest rates; these are generally reported to be much lower in West African countries. Available data are now old: not beyond 2010. Up until that time, in the Republic of South Africa, there appears to have been a slight decline in oral cancer rates, except in Black females, but a rise this millennium in cancer of the oropharynx, especially in Coloureds (mixed-race). At least until 2002, the Human Immunodeficiency Virus infection (HIV) pandemic had little or no stimulating influence on the incidence rates of oral squamous carcinoma in South Africa, although Kaposi’s sarcoma has been a major burden in the past. Asian and mixed-race South African females had the highest levels of oral squamous cell carcinomas in the <45 year age group. Conclusion: The quality of cancer registry data in sub-Saharan Africa is variable, unreliable and out of date, suggesting gross under-ascertainment. Records of all causes of death are poor, which can result in both under- and over-attribution of cancer mortality. Improvements of the necessary resources for cancer registration and death certification deserve a high priority.