Three-Tesla magnetic resonance-guided prostate biopsy in men with increased prostate-specific antigen and repeated, negative, random, systematic, transrectal ultrasound biopsies: detection of clinically significant prostate cancers.

BACKGROUND: Patients with elevated prostate-specific antigen (PSA) and one or more previous negative transrectal ultrasound (TRUS) biopsy sessions are subject to diagnostic uncertainty due to TRUS-biopsy undersampling. Magnetic resonance (MR)-guided biopsy (MRGB) has shown high prostate cancer (PCa)-detection rates in studies with limited patient numbers.

OBJECTIVE: Determine the detection rate of (clinically significant) PCa for MRGB of cancer-suspicious regions (CSRs) on 3-T multiparametric MR imaging (MP-MRI) in patients with elevated PSA and one or more negative TRUS-biopsy sessions.

DESIGN, SETTING, AND PARTICIPANTS: Of 844 patients who underwent 3-T MP-MRI in our referral centre between March 2008 and February 2011, 438 consecutive patients with a PSA >4.0 ng/ml and one negative TRUS-biopsy session or more were included. MRGB was performed in 265 patients. Exclusion criteria were existent PCa, endorectal coil use, and MP-MRI for indications other than cancer detection.

INTERVENTION: Patients underwent MRGB of MP-MRI CSRs.

MEASUREMENTS: (Clinically significant) MRGB cancer-detection rates were determined. Clinically significant cancer was defined by accepted (i.a. Epstein and d'Amico) criteria based on PSA, Gleason score, stage, and tumour volume. Follow-up PSA and histopathology were collected. Sensitivity analysis was performed for patients with MP-MRI CSRs without MRGB.

RESULTS AND LIMITATIONS: In a total of 117 patients, cancer was detected with MRGB (n=108) or after negative MRGB (n=9). PCa was detected in 108 of 438 patients (25%) and in 41% (108 of 265) of MRGB patients. The majority of detected cancers (87%) were clinically significant. Clinically significant cancers were detected in seven of nine (78%) negative MRGB patients in whom PCa was detected during follow-up. Sensitivity analysis resulted in increased cancer detection (47-56%). Complications occurred in 0.2% of patients (5 of 265).

CONCLUSIONS: In patients with elevated PSA and one or more negative TRUS-biopsy sessions, MRGB of MP-MRI CSRs had a PCa-detection rate of 41%. The majority of detected cancers were clinically significant (87%).