Free PSA/total PSA ratio increases the detection rate of prostate cancer in twelve-core biopsy.

Background: In the present study, we compared 12- with 8-core biopsy in patients with prostate-specific antigen (PSA) levels of 4.0-20.0 ng/ml. We also examined whether the free/total (F/T) PSA ratio is useful for cancer detection in 12-core biopsy.
Methods: A total of 419 men with PSA level between 4.0 and 20.0 ng/ml underwent transrectal ultrasound-guided transperineal needle biopsies of the prostate. Of these men, 235 underwent 8-core biopsy and 184 underwent 12-core biopsy. We compared the cancer detection rate between the 8- and 12-core biopsy groups by analyzing the PSA value, and especially the F/T PSA ratio.
Results: The cancer detection rate in the 12-core group (35.9%) was significantly higher than in the 8-core group (23.8%). In cases of PSA level of 4.0-20.0 ng/ml with F/T PSA ratio less than 0.11, the cancer detection rate was 53.1% in the 12-core biopsy group. Performing 12-core biopsy resulted in a marked difference of cancer detection rate between men with F/T PSA ratio less than 0.11 and those with more than 0.12 in gray zone PSA (48.2% and 17.5%, respectively).
Conclusions: Twelve-core biopsy can achieve a higher detection rate of prostate cancer than 8-core biopsy using F/T PSA ratio.
(Copyright 2009 S. Karger AG, Basel.)