title: Tumour growth fraction measured by immunohistochemical staining of Ki67 is an independent prognostic factor in preoperative prostate biopsies with small-volume or low-grade prostate cancer.
abstract: Accurate prognostic parameters in prostate biopsies are needed to better counsel individual patients with prostate cancer. We evaluated the prognostic impact of morphologic and immunohistochemical parameters in preoperative prostate cancer biopsies. A consecutive series of prostate biopsies of 279 men (72% with clinical stage T1c and 23% with T2) who subsequently underwent radical prostatectomy was prospectively analysed for Gleason score, number and percentage of positive cores (NPC, PPC), total percentage of biopsy tissue with tumour (TPT), maximum tumour percentage per core (MTP), and expression of Ki67, Bcl-2 and p53. All biopsy features were significantly associated with at least one feature of the radical prostatectomy specimen. pT stage was independently predicted by PSA, seminal vesicle invasion by Ki67 LI, positive margins by PSA and MTP, large tumour diameter by PSA and PPC, and Gleason score by biopsy Gleason score, MTP, and Ki67 LI, respectively. Biopsy Gleason score, NPC (1 vs. >1), TPT (<7 vs. >or=7%), and Ki67 LI (<10 vs. >or=10%) were significant predictors of biochemical recurrence after radical prostatectomy (p < 0.01, each). KI67 LI was the only independent prognostic factor in case of a low TPT (<7%) or low Gleason score (<7), the hazard ratio being 6.76 and 6.44, respectively. In summary, preoperative Gleason score, NPC, TPT and Ki67 LI significantly predict the risk of recurrence after radical prostatectomy, and Ki67 is an independent prognosticator in biopsies with low-volume or low-grade prostate cancer. Analysis of Ki67 LI in these biopsies may help to better identify patients with clinically insignificant prostate cancer.
authors.affiliation: Division of Urology, St. Clara Hospital, Basel, Switzerland.
authors.forename: Tobias
authors.initials: T
authors.lastname: Zellweger
authors.forename: Sarah
authors.initials: S
authors.lastname: Günther
authors.forename: Inti
authors.initials: I
authors.lastname: Zlobec
authors.forename: Spasenija
authors.initials: S
authors.lastname: Savic
authors.forename: Guido
authors.initials: G
authors.lastname: Sauter
authors.forename: Holger
authors.initials: H
authors.lastname: Moch
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Mattarelli
authors.forename: Tobias
authors.initials: T
authors.lastname: Eichenberger
authors.forename: Enrico
authors.initials: E
authors.lastname: Curschellas
authors.forename: Hansjörg
authors.initials: H
authors.lastname: Rüfenacht
authors.forename: Alexander
authors.initials: A
authors.lastname: Bachmann
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Gasser
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mihatsch
authors.forename: Lukas
authors.initials: L
authors.lastname: Bubendorf
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001707:Biopsy, Needle; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000378:metabolism; D009367:Neoplasm Staging; D011300:Preoperative Care; D011379:Prognosis; D011446:Prospective Studies; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D018570:Risk Assessment; D012307:Risk Factors; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53