Racial Differences in Breast Cancer Incidence and Mortality Among Kansas Women – a Trend Analysis Study

BACKGROUND:  Racial variation in breast cancer incidence and mortality is seen in the United States. Factors responsible for higher breast cancer incidence and mortality rates include demographic characteristics, such as geographic distribution, social economic status, and tumor biology. The purpose of this study is to examine racial disparities in breast cancer incidence and mortality among Kansas women.

METHODS:  The Kansas Cancer Registry (KCR) and mortality datasets were analyzed to calculate the age-adjusted incidence and mortality rates and racial trends, stratified by age, population density, and stage of tumor diagnosis subgroups for the period 2000-2014. Analyses were restricted to women 40 years or older. Joinpoint regression analysis was used to assess the magnitude and direction of incidence and mortality trends by annual percentage change among White and non-White women.

RESULTS:  In Kansas, between 2000 and 2013, incidence rates of invasive breast cancer in women 40 years or older showed a statistically significant annual decline among White (-0.93%), whereas the rates among non-White remained relatively stable. Mortality rates of breast cancer in women 40 years or older declined considerably each year for both White (-2.95%) and non-White (-2.98%) for the period 2005-2014. In White women, a statistically significant annual decline in incidence rates were observed for those aged 50-64 and those whose tumors were diagnosed at localized stage between 2000 and 2004. Statistically significant annual decline was seen for those living in both rural and urban counties and those whose tumors were diagnosed at regional/distant stage during the whole study period 2000-2013. In non-White women, a substantial decline in incidence rates was seen for those aged 65 and older, however, a reverse pattern of significant results were observed between 2000-2008 and 2008-2013. A significant annual decline in mortality trends in White women was seen for those aged 50-64 and those who lived in urban counties during 2005-2014. However, significant decline was only observed in non-White women who lived in urban counties.

CONCLUSIONS:  These data provide information regarding racial disparities in female breast cancer between White and non-White women in Kansas. Therefore, a concerted effort aimed at increasing preventive, screening, and surveillance activities among non-White women is needed. These will include cancer control efforts such as health education and access to early detection and treatment services.