Obesity independently affects prostate cancer screening

Physicians should consider the impact of a patient’s body mass index, regardless of race, when interpreting prostate cancer screening test results, according to the authors of a study to be published in Cancer.

Obese African-American and Caucasian men had lower levels of PSA and free PSA than did men with a normal body mass index, suggesting that an obese man with a slightly elevated PSA may be at higher risk for prostate cancer than a man with a normal BMI.

Jay H. Fowke, PhD, and colleagues at Vanderbilt University Medical Center in Nashville tested blood from 150 African-Americans and 149 Caucasians and found that PSA and free PSA levels decreased with increasing BMI. This inverse relationship was strongest in men under 60 years of age. Race did not affect any association between PSA or percentage of free PSA and BMI. In addition, percentage of free PSA increased with height.

“Whether equal PSA levels in an obese versus a thin man may convey the same biologic relevance is unclear, but our findings suggest that clinical suspicion might be heightened with a marginally elevated PSA level in an obese person,” the authors wrote.