Where Do Transrectal Ultrasound- and Magnetic Resonance Imaging-guided Biopsies Miss Significant Prostate Cancer?

OBJECTIVE: To identify the location of missed significant prostate cancer (sPCa) lesions by transrectal ultrasound-guided biopsy (TRUSbx ) and multiparametric magnetic resonance imaging-guided biopsy (mpMRIbx ) in men undergoing repeat biopsies.

MATERIALS AND METHODS: A total of 289 men with prior negative TRUSbx underwent multiparametric magnetic resonance imaging. The location of any suspicious lesion was registered and scored using Prostate Imaging Reporting and Data System version 1 classification according to the likelihood of being sPCa. All patients underwent repeat transrectal ultrasound-guided biopsy (reTRUSbx ) and targeted mpMRIbx (image fusion) of any suspicious lesion. Biopsy results were compared and the locations of missed sPCa lesions were registered. Cancer significance was defined as (1) any core with a Gleason score of >6, (2) cancer core involvement of ≥50% and for reTRUSbx on patient level, and (3) the presence of ≥3 positive cores.

RESULTS: Of the 289 patients, prostate cancer was detected in 128 (44%) with 88 (30%) having sPCa. Overall, 165 separate prostate cancer lesions were detected with 100 being sPCa. Of these, mpMRIbx and reTRUSbx detected 90% (90/100) and 68% (68/100), respectively. The majority of sPCa lesions (78%) missed by primary TRUSbx were located either anteriorly or in the apical region. Missed sPCa lesions at repeat biopsy were primarily located anteriorly (84%) for reTRUSbx (n = 27/32) and posterolateral midprostatic (60%) for mpMRIbx (n = 6/10).

CONCLUSION: Both TRUSbx and mpMRIbx missed sPCa lesions in specific segments of the prostate. Missed sPCa lesions at repeat biopsy were primarily located anteriorly for TRUSbx and posterolateral midprostatic for mpMRIbx . Localization of these segments may improve biopsy techniques in men undergoing repeat biopsies.