BERKELEY, CA (UroToday.com) - Percent-free prostate-specific antigen (PSA) testing has been suggested to increase the specificity and decrease the number of unnecessary biopsies. Men with prostate cancer tend to have a lower percent-free PSA than patients with benign prostatic hyperplasia. However, men with impaired renal function would be expected to have elevated percent-free PSA.
Recently, studies about the association between percent-free PSA and renal function demonstrated that diminished renal function was significantly associated with a higher percent-free PSA. Therefore, using the current percent free PSA cutoff level has been suspected to cause prostate cancer patients, with decreased renal function, to be misdiagnosed as having benign disease. We investigated the relationship between percent free PSA and glomerular filtration rate (GFR) while adjusting for body mass index, age, and prostate size. Percent-free PSA was independently influenced by prostate size (positive correlation) and GFR (negative correlation) in the non-cancer group, while it was influenced by only prostate size (positive correlation) in the cancer cohort.
According to these results, screening with current cutoff value of percent-free PSA can be applied to the patients with impaired renal function.
Jae Young Park, MD as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.
Department of Urology, College of Medicine, Korea University Ansan Hospital, Korea University, 516 Gojan-dong, Danwon-gu, Ansan, 425-707, Republic of Korea
Association between percent-free prostate-specific antigen and glomerular filtration rate in transrectal ultrasound-guided biopsy-proven patients with prostate-specific antigen levels ranging from 4 to 10 ng/ml - Abstract