Although it is well known that African American men have a higher incidence and mortality from prostate cancer, the reasons behind this epidemiological phenomenon are not clearly defined. If risk factors for the development of prostate cancer can be identified, it is possible that primary care practitioners may be able to focus on risk reduction strategies. To this end, the study by Barrington et al1 in this issue of JAMA Oncology presents results via joint-effects modeling to describe the effect of an interaction between race and obesity on risk of prostate cancer. Barrington et al1 have identified differential body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) as contributing to the increased incidence of this disease in a cohort of African American men enrolled in the SELECT (Selenium and Vitamin E Cancer Prevention Trial). There appears to be a 4 times greater risk of developing prostate cancer in African American men as the BMI increases (28% for BMI < 25 vs 103% for BMI ≥ 35). Furthermore, the risk of developing high-grade disease (defined as a Gleason score ≥7) was associated with higher BMI in all patients, although this risk was higher in African American men compared with non-Hispanic white men (hazard ratio, 1.81). Despite the limitations inherent in the methodology utilized for the analysis and the inability to define a clear mechanism behind the association between BMI and risk, the findings do provide a further rationale for weight reduction and a target BMI for clinicians to aim for in care of African American men.
Conflict of Interest Disclosures: None reported.
Thomas CR. Targeted Reduction in Body Mass Index Is a Worthwhile Risk Reduction Strategy for Prostate Cancer. JAMA Oncol. 2015;1(3):349. doi:10.1001/jamaoncol.2015.0514