Prostate cancer (CaP) is the most common cancer found in men in the United States. African American men (AAM) are at greater risk of dying from prostate cancer. Our proposal aims to study a possible reason why AAM have worse CaP. One possibility is that obesity and/or race can cause misinterpretation of PSA test results. PSA is the test used to screen men for CaP. The possible mechanism which causes these unreliable PSA test results may be the amount of blood in the human body. We believe that obese men have more blood and it dilutes the PSA, leading to deceptively lower PSA levels. We also believe that AAM have less blood and that this causes deceptively higher PSA levels. In the past, blood volumes were estimated using height and weight. We believe that to adequately study the relationships between race, obesity, and blood volume, we have to directly measure blood volume using a newly developed method. We thus plan to examine the associations between race, blood volume, and body measurements in order to suggest ways to analyze PSA tests differently to minimize misinterpretation and possibly improve the outcomes of AAM with CaP.

AAM have the most to gain from this study as race is the major consideration in the analysis of data; however, because we intend to examine how obesity affects PSA tests, obese men from all races will likely benefit. Early detection of CaP is an important principle of treatment as late detection may render treatments ineffective. Thus, improving the way CaP is screened for would be of great benefit to all men who choose to get screened. We plan to make available on the internet accurate calculators of blood volume. This will be used to make sure that obesity and race do not cause misinterpretation of PSA results. An immediate benefit would be increasing the pick-up rate of CaP. Whether this would eventually mean fewer deaths due to CaP has to be further studied. However, a very important implication for our study, if successful, is that blood volume can affect virtually any blood-based test for diagnosis and management of any disease. Thus, our project could be the foundation for studying racial differences in other blood-based disease markers.

As incoming faculty at Duke University, the support from this Health Disparity Award will be invaluable. My ultimate objective is to be able to transition into my new role as Assistant Professor of Surgery in the most productive manner possible, to integrate the skills and knowledge I have gained through my research fellowships, and, by the end of this research project, achieve independence to carry out further studies focused on developing feasible strategies to reduce racial disparity in CaP. My first career goal is to become a successful health disparity scientist performing bench-top or database research and finding ways to translate these findings into readily useable strategies to reduce health disparities. My secondary career goal is to acquire experience to develop into an outstanding mentor-teacher.

To achieve my goals I will be mentored by Dr. Stephen Freedland, who is an expert on CaP health disparities. I will complete a Master of Public Health degree with special emphasis on epidemiology and racial disparities. Cultivation of my research skills will be a priority of this program with studies centering on CaP health disparities. I will undertake greater teaching responsibilities in my new faculty position. I will also participate in various academic activities at Duke. Lastly, the resources and academic environment in Duke will boost my productivity tremendously. Taken together, these components shall insure my academic growth and maturity into a fully-independent CaP health disparity research expert.

The research project proposed in this grant is the perfect vehicle to successfully implement my planned career development program. This study will establish the validity of my initial findings that greater blood volume results in lower PSA in obese men. We will also establish why AAM have higher PSA levels compared to Caucasian men. Dr. Freedland and I have successfully collaborated as mentor-trainee and our team-oriented approach will insure my smooth transition into independence. The study is a good springboard for teaching younger trainees in the research team regarding possible sources of racial disparity in CaP. The study will allow me to form collaborations with other health disparity experts, present at scientific conferences, and gain experience in directly managing research support staff. Thus, the research project is totally aligned with the goal of my development into an established health disparities researcher.