Comparison of TRUS and combined MRI-targeted plus systematic prostate biopsy for the concordance between biopsy and radical prostatectomy pathology.

AIM

To evaluate the accuracy in histologic grading of MRI/US image fusion biopsy by comparing conventional 12-core TRUS-Bx at radical prostatectomy specimens (RP).

METHODS

Consecutive patients diagnosed prostate cancer (127 with combination of both targeted biopsy (TBx) plus systematic biopsies (SBx) and separate patient cohort of 330 conventional TRUS-Bx without mpMRI) with a PSA level of <20 ng/mL prior to RP were included. The primary end point was the grade group concordance between biopsy and RP pathology according to biopsy technique.

RESULTS

Clinically significant prostate cancer detection was 51.2% for TRUS-Bx, 49.5% for SBx, 67% for TBx and 75.7% for TBx + SBx. Upgrading and downgrading of at least one Gleason Grade Group (GGG) was recorded in 43.3%/ 6.7% patients of the TRUS-Bx and in 20.5%/ 22% of the TBX + SBx group, respectively (all P < .001). Concordance level was detected to be significantly higher for ISUP 1 in combined TBx + SBx method compared to conventional TRUS-Bx (61.3% vs 37.9%, P = .014). In ISUP 1 exclusively, significant upgrading was seen in TRUS-Bx (62.1%) when compared to TBx (41.4%) and TBx + SBx (38.7%).

CONCLUSIONS

MRI-targeted biopsies detected more significant PCa than TRUS-Bx but, superiority in significant cancer detection appears as a result of inadvertant selective sampling of small higher grade areas. Within an otherwise low grade cancer and does not reflect accurate GGG final surgical pathology. TBx + SBx has the greatest concordance in ISUP Grade 1 with less upgrading which is utmost important for active surveillance.