Transperineal template prostate-mapping biopsies: an evaluation of different protocols in the detection of clinically significant prostate cancer.
To determine whether modified transperineal template prostate-mapping (TTPM) biopsy protocols, altering the template or the biopsy density, have sensitivity and negative predictive value (NPV) equal to full 5-mm TTPM.



Retrospective analysis of an institutional registry including treatment-naïve men undergoing 5-mm TTPM biopsy analysed in a 20-zone fashion. The value of three modified strategies was assessed by comparing the information provided by selected zones against full 5-mm TTPM. Strategy 1, did not consider the findings of anterior areas; strategies 2 and 3 simulated a reduced biopsy density by excluding intervening zones. A bootstrapping technique was used to calculate reliable estimates of sensitivity and NPV of these three strategies for the detection of clinically significant disease (maximum cancer core length ≥4 mm and/or Gleason score ≥3 + 4).



In all, 391 men with a median (interquartile range, IQR) age of 62 (58-67) years were included. The median (IQR) PSA level and PSA density were 6.9 (4.8-10) ng/mL and 0.17 (IQR 0.12-0.25) ng/mL/mL, respectively. A median (IQR) of 6 (2-9) cores out of 48 (33-63) taken per man were positive for prostate cancer. No cancer was detected in 67 men (17%), whilst low-, intermediate- and high-risk disease was identified in 78 (20%), 80 (21%), and 166 (42%), respectively. Strategy 1, 2 and 3 had sensitivities of 78% [95% confidence interval (CI) 73-84%], 85% (95% CI 80-90%) and 84% (95% CI 79-89%), respectively. The NPVs of the three strategies were 73% (95% CI 67-80%), 80% (95% CI 74-86%) and 79% (95% CI 72-84%), respectively.



Altering the template or decreasing sampling density has a substantial negative impact on the ability of TTPM biopsy to exclude clinically significant disease. This should be considered when modified TTPM biopsy strategies are used to select men for tissue-preserving approaches, and when modified TTPM are used to validate new diagnostic tests.
Division of Surgery and Interventional Science, University College Hospitals NHS Foundation Trust, London, UK.|Department of Urology, University College Hospitals NHS Foundation Trust, London, UK.|Department of Urology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Massimo
M
Valerio
Division of Surgery and Interventional Science, University College Hospitals NHS Foundation Trust, London, UK.|Department of Urology, University College Hospitals NHS Foundation Trust, London, UK.
Chukwuemeka
C
Anele
Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Susan C
SC
Charman
Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Jan
J
van der Meulen
Department of Histopathology, University College Hospitals NHS Foundation Trust, London, UK.
Alex
A
Freeman
Department of Histopathology, University College Hospitals NHS Foundation Trust, London, UK.
Charles
C
Jameson
Department of Urology, Royal Free Hospital NHS Trust, London, UK.
Paras B
PB
Singh
Division of Surgery and Interventional Science, University College Hospitals NHS Foundation Trust, London, UK.|Department of Urology, University College Hospitals NHS Foundation Trust, London, UK.
Mark
M
Emberton
Division of Surgery and Interventional Science, University College Hospitals NHS Foundation Trust, London, UK.|Department of Urology, University College Hospitals NHS Foundation Trust, London, UK.
Hashim U
HU
Ahmed
D000368:Aged; D001706:Biopsy / Q000379:methods; D002985:Clinical Protocols; D006801:Humans; D008297:Male; D008875:Middle Aged; D010502:Perineum; D011237:Predictive Value of Tests; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
biopsy; prostate neoplasms; template-mapping biopsy