Mapping cancer mortality-to-incidence ratios to illustrate racial and sex disparities in a high-risk population.

BACKGROUND: Comparisons of incidence and mortality rates are the metrics used most commonly to define cancer-related racial disparities. In the US, and particularly in South Carolina, these largely disfavor African Americans (AAs). Computed from readily available data sources, the mortality-to-incidence rate ratio (MIR) provides a population-based indicator of survival. METHODS: South Carolina Central Cancer Registry incidence data and Vital Registry death data were used to construct MIRs. ArcGIS 9.2 mapping software was used to map cancer MIRs by sex and race for 8 Health Regions within South Carolina for all cancers combined and for breast, cervical, colorectal, lung, oral, and prostate cancers. RESULTS: Racial differences in cancer MIRs were observed for both sexes for all cancers combined and for most individual sites. The largest racial differences were observed for female breast, prostate, and oral cancers, and AAs had MIRs nearly twice those of European Americans (EAs). CONCLUSIONS: Comparing and mapping race- and sex-specific cancer MIRs provides a powerful way to observe the scope of the cancer problem. By using these methods, in the current study, AAs had much higher cancer MIRs compared with EAs for most cancer sites in nearly all regions of South Carolina. Future work must be directed at explaining and addressing the underlying differences in cancer outcomes by region and race. MIR mapping allows for pinpointing areas where future research has the greatest likelihood of identifying the causes of large, persistent, cancer-related disparities. Other regions with access to high-quality data may find it useful to compare MIRs and conduct MIR mapping.

Head and neck cancer disparities in South Carolina: descriptive epidemiology, early detection, and special programs.

Recognizing that relatively easily detected precancerous lesions precede many cancers, there is a need to investigate the effectiveness of early interventions on the reduction of incidence rates in well-designed large randomized control trials. If early detection can reduce mortality rates of OPCA, evaluation of the capacity of dentists and physicians to screen or detect precancerous lesions related to oral cancers may have merit. Presently, there is a paucity of research regarding ecological barriers in the healthcare system, and improving access to adequate dental and medical care among the rural minority population in South Carolina certainly deserves emphasis. Additional research, specific to South Carolina, which includes comprehensive assessment of multiple social, behavioral, and biological factors, is needed. Interdisciplinary collaboration will be particularly important to dissect key factors contributing to the racial disparities observed in South Carolina. These differences should be taken into account while recommending and implementing public health strategies for the control of these cancers.