Transperineal MRI visually-targeted prostate biopsies compared to
template mapping biopsy in 400 men requiring further risk
Grey ADR, Hartington TR, Allen C, Arya M, Emberton M, Freeman A, Jameson C, Kirkham AP, Moore CM, Punwani S, Ramachandran N,
Trevisan G, Walkden M, Ahmed HU.
• Transperineal template mapping prostate biopsies are highly accurate in
detecting and ruling-out clinically significant prostate cancer. However, they can
lead to over-detection of clinically insignificant disease and high resource use.
• Targeted transperineal biopsy may overcome these problems. We aimed to
evaluate the concordance between a MRI-targeted strategy and a whole-gland
mapping in men undergoing accurate risk stratification.
• 400 consecutive men underwent transperineal biopsy (TPbx) with both zonal
and visually targeted cores.
• All had prior multiparametric MRI (T2W, DWI, DCE) and Likert score applied to
• Primary outcome detection of clinically significant prostate cancer (Primary
Gleason pattern 4 or maximum cancer core length (MCCL) > 6mm).
• Secondary outcomes included detection of clinically insignificant cancer.
• Mean age 65 years (SD+/-22),
• Mean PSA 9.5 (SD+/-16.9),
• Core numbers
• MRI-targeted biopsy 3.6 (SD+/-2.1)
• Mapping biopsy 42.7(SD+/-20).
• Cancer Detection
• All cancer
• MRI targeted 263 cases (66%)
• Mapping biopsy 339 cases (85%)
• Clinically significant cancer
• MRI targeted 150 cases (37.4%)
• Mapping biopsy 177 cases (43.9%
• MRI-targeted biopsy detected an additional 39 (9.8%) cases of
clinically significant prostate cancer missed by mapping biopsy.
• Mapping biopsy detected 64 (16%) cases missed by MRI-targeted
• Mapping biopsy detected 66 (16.5%) cases of clinically insignificant
prostate cancer (Gleason pattern 3 AND MCCL <4mm) that were
avoided by a MRI-targeted approach.
• A transperineal MRI-targeted biopsy strategy has a high detection rate of clinically
significant disease with fewer biopsies. It also reduces the detection of clinically
insignificant prostate cancer.
• Both strategies missed some disease. Careful consideration by patient and
physician should be given to the balance between over and under diagnosis, biopsy
burden and resource expenditure.
• The emerging image fusion technologies may improve the accuracy of targeted