title: Extended 21-sample needle biopsy protocol for diagnosis of prostate cancer in 1000 consecutive patients.
abstract: OBJECTIVE
  To prospectively evaluate the diagnostic yield of a 21-sample ultrasound-guided needle biopsy protocol as the initial diagnostic strategy for detection of prostate cancer.
  
  
  METHODS
  Between December 2001 and October 2005, 1000 consecutive patients underwent 21-sample needle biopsies under local anesthesia, comprising sextant biopsies, 3 additional posterolateral biopsies in each peripheral zone, 3 biopsies in each transition zone (TZ), and 3 biopsies in the midline peripheral zone. Each prostate core was numbered and analyzed separately. The patients were divided into subgroups according to the result of digital rectal examination (DRE), serum prostate-specific antigen (PSA), and prostate volume. We evaluated the cancer detection rate overall and in each subgroup. We compared the results of our biopsy protocol to those from 6-, 12-, and 18-core biopsy protocols by analyzing only those cores from our protocol that would correspond to these biopsy schemes.
  
  
  RESULTS
  Cancer detection rates using 6 biopsy samples (sextant biopsies only), 12 samples (sextant plus lateral biopsies), 18 samples (sextant, lateral, and TZ biopsies), and 21 samples (sextant, lateral, TZ, plus midline biopsies) were 31.7%, 38.7%, 41.5%, and 42.5%, respectively. The 12-sample procedure improved the cancer detection rate by 22% compared with the 6-sample procedure (p=0.0001). The improvement in the diagnostic yield was most marked in patients with a prostate volume > or =55 ml (36.9%), in patients with normal DRE (26.6%), and in patients with PSA<4 (37.5%). The addition of TZ biopsies to a 12-biopsy scheme increased the diagnostic yield by 7.2% overall (p=0.023). Only 10 of 425 (2.3%) patients were diagnosed on the sole basis of midline biopsies.
  
  
  CONCLUSIONS
  Patients with suspected localized prostate cancer should be offered at least 12 biopsies in the peripheral zone and far lateral peripheral zone (statistically significant). TZ biopsies have to be considered, because these biopsies improve the diagnostic yield. For patients with abnormal DRE and/or PSA> or =20 ng/ml, the 6-biopsy scheme seems sufficient (statistically), but 6 far lateral peripheral zone biopsies as well as the TZ biopsies add little incremental value (not significant). Evidence does not support the use of routine midline peripheral zone needle biopsies in the initial biopsy to enhance the detection of prostate cancer.
authors.affiliation: INSERM U841EQ07, Department of Urology APHP, Créteil, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Guichard
authors.forename: Stéphane
authors.initials: S
authors.lastname: Larré
authors.forename: Andrea
authors.initials: A
authors.lastname: Gallina
authors.forename: Adi
authors.initials: A
authors.lastname: Lazar
authors.forename: Hugo
authors.initials: H
authors.lastname: Faucon
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Chemama
authors.forename: Yves
authors.initials: Y
authors.lastname: Allory
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Patard
authors.forename: Dimitri
authors.initials: D
authors.lastname: Vordos
authors.forename: Andras
authors.initials: A
authors.lastname: Hoznek
authors.forename: René
authors.initials: R
authors.lastname: Yiou
authors.forename: Laurent
authors.initials: L
authors.lastname: Salomon
authors.forename: Claude Clément
authors.initials: CC
authors.lastname: Abbou
authors.forename: Alexandre
authors.initials: A
authors.lastname: de la Taille
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D018084:Ultrasonography, Interventional
chemical_list: D017430:Prostate-Specific Antigen