MRI-Targeted, Systematic, or Combined Biopsy for Detecting Clinically Significant Prostate Cancer

The aim of this study was to assess MRI-targeted, systematic, or combined prostate biopsy for diagnosing prostate cancer to identify opportunities for diagnostic accuracy improvement.

This institutional review board-approved, retrospective study, performed at a large, quaternary hospital, included all men undergoing prostate multiparametric MRI (mpMRI) from January 1, 2015, to December 31, 2019, with prostate-specific antigen ≥ 4 ng/mL, biopsy target on mpMRI (Prostate Imaging Reporting and Data System [PI-RADS] 3-5 lesion), and combined targeted and systematic biopsy ≤6 months after MRI. Analysis included the highest grade lesion per patient. The primary outcome was prostate cancer diagnosis by grade group (GG; 1, 2, and ≥3). Secondary outcomes were rates of cancer upgrading by biopsy type and cancer proximity to the targeted biopsy site in patients upgraded by systematic biopsy.

Two hundred sixty-seven biopsies (267 patients) were included; 94.4% (252 of 267) were biopsy naive. The most suspicious mpMRI lesion was PI-RADS 3 in 18.7% (50 of 267), PI-RADS 4 in 52.4% (140 of 267), and PI-RADS 5 in 28.8% (77 of 267). Prostate cancer was diagnosed in 68.5% (183 of 267): 22.1% (59 of 267) GG 1, 16.1% (43 of 267) GG 2, and 30.3% (81 of 267) GG ≥ 3. Combined biopsy (124 of 267) yielded more GG ≥ 2 prostate cancer diagnoses than systematic (87 of 267) or targeted (110 of 267) biopsy alone. More GG ≥ 2 cancers were upgraded by targeted biopsy than by systematic biopsy (P = .0062). Systematic biopsy upgrades were in close proximity to the targeted biopsy site in 42.1% (24 of 57); GG ≥ 3 cancers 62.5% (15 of 24) constituted most proximal misses.

In men with prostate-specific antigen ≥ 4 ng/mL and PI-RADS 3, 4, or 5 lesion on mpMRI, combined biopsy led to more prostate cancer diagnoses than targeted or systematic biopsy alone. Cancers upgraded by systematic biopsy proximal and distant from the targeted biopsy site may indicate opportunities for biopsy and mpMRI improvement, respectively.