title: Diagnostic performance of initial transperineal 14-core prostate biopsy to detect significant cancer.
abstract: OBJECTIVE
  To investigate cancers missed by extended transperineal (TP) 14-core biopsy (TP14PBx) and examined its diagnostic performance.
  
  
  METHODS
  We evaluated 744 men with prostate-specific antigen (PSA) levels in the range 2.5-20 ng/mL or abnormal digital rectal examination underwent three-dimensional 26-core prostate biopsy (3D26PBx), a combination of TP14PBx and transrectal 12-core biopsy (TR12PBx), at initial biopsy. Of 269 patients diagnosed with cancer, 127 subsequently underwent radical prostatectomy (RP). Cancers were grouped into TP-positive cancers (detected through TP14PBx) and TP-negative cancers (those not detected through TP14PBx but detected through TR12PBx). Clinicopathological characteristics and cancer locations of TP-negative cancers were evaluated. For cancer location analysis, the prostate was divided into apex, midprostate, and base regions.
  
  
  RESULTS
  Thirty-seven (14 %) TP-negative cancers were found in 269 biopsy-positive cancers. Median number of positive cores in TP-negative cancers was significantly lower than that in TP-positive cancers (1 vs. 5, p < 0.001). TP-negative cancers had biopsy Gleason score (GS) of 7 or less in 87 % of cases and had significantly lower biopsy GS than those of TP-positive cancers (p = 0.028). Of 20 TP-negative cancers treated with RP, 70 % (14/20) were insignificant cancers (GS <4+3, volume <0.5 cc, and organ-confined disease). Of all significant cancers treated with RP, 6 % (6/99) were missed by TP14PBx. TP-negative cancers treated with RP were located more frequently in the apex than in the base (85 vs. 20 %, p < 0.001).
  
  
  CONCLUSIONS
  Initial TP14PBx provides sufficient detectability of significant cancers despite a small risk of missing cancers located in the prostate apex.
authors.affiliation: Department of Urology, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Takeshita
authors.forename: Noboru
authors.initials: N
authors.lastname: Numao
authors.forename: Toshiki
authors.initials: T
authors.lastname: Kijima
authors.forename: Minato
authors.initials: M
authors.lastname: Yokoyama
authors.forename: Junichiro
authors.initials: J
authors.lastname: Ishioka
authors.forename: Yoh
authors.initials: Y
authors.lastname: Matsuoka
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Koga
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Saito
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Masuda
authors.forename: Satoru
authors.initials: S
authors.lastname: Kawakami
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Junji
authors.initials: J
authors.lastname: Yonese
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Fujii
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kihara
mesh_terms: D062005:Biopsy, Large-Core Needle / Q000379:methods*; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D010502:Perineum; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D015203:Reproducibility of Results; D012189:Retrospective Studies