Can 3-Tesla pelvic phased-array multiparametric MRI avoid unnecessary repeat prostate biopsy in patients with PSA <...

The aim of this study was to evaluate multiparametric pelvic magnetic resonance imaging (mpMRI) accuracy in prostate cancer (PCa) diagnosis.

From June 2011 to March 2014, 100 patients (median age, 64 years) with negative digital rectal examination underwent repeat transperineal saturation biopsy (SPBx; median, 29 cores) for persistent prostate-specific antigen (PSA) values between 4.1 and 10 ng/mL with free/total PSA ≤ 25%. All patients underwent mpMRI using a 3.0-Tesla scanner (ACHIEVA; Philips) equipped with surface 16 channels phased-array coil and lesions suspicious for PCa were submitted to additional targeted biopsies.

A T1c PCa was found in 37 (37%) of cases; SPBx and mpMRI targeted biopsy diagnosed 34 (34%) and 29 (29%) cancers, missing 3 (all of the anterior zone) and 8 cancers (7 and 1 of the lateral margins and anterior zone, respectively); in detail, mpMRI missed 8 (21.7%) PCa characterized by minimal histological disease at risk for insignificant cancer. The diameter of the mpMRI suspicious lesion was significantly correlated with the diagnosis of PCa with poor Gleason score (P = .005). The detection rate of cancer for each mpMRI core was 40.7%; moreover, mpMRI would have spared 31 (31%) unnecessary SPBx. Diagnostic accuracy, sensitivity, specificity, and positive and negative predictive value of mpMRI in diagnosing overall cancer versus significant PCa was 82.6% versus 81.3%, 82.2% versus 100%, 77.8% versus 78.9%, 65.4% versus 55.8%, and 95.5% versus 100%, respectively.

mpMRI targeted biopsy improved diagnosis of significant anterior zone PCa, missing cancers at risk for clinically insignificant disease; moreover, the diameter of the lesion on mpMRI was significantly predictive of aggressive PCa.