title: Characterization of prostate cancer incidentally detected in radical cystoprostatectomy specimens from Japanese men with bladder cancer.
abstract: OBJECTIVE
  The objective of this study was to investigate and characterize the clinicopathological features of incidentally detected prostate cancer in radical cystoprostatectomy specimens from Japanese men with bladder cancer.
  
  
  METHODS
  We reviewed the pathological reports of 251 male patients who underwent radical cystoprostatectomy for bladder cancer at our institution and identified men with incidentally detected prostate cancer in these specimens. Clinicopathological data of patients with incidental prostate cancer in cystoprostatectomy specimens (group A) were compared with those of 193 patients with clinically detected prostate cancer who underwent radical prostatectomy (group B). Immunohistochemical staining was also performed to measure the expression levels of Ki-67, p53 and androgen receptor (AR) proteins in specimens from both groups A and B.
  
  
  RESULTS
  In this series, a total of 31 patients (12.3%; group A) were incidentally diagnosed as having prostate cancer in radical cystoprostatectomy specimens. Clinically significant cancer, defined as any tumor greater than 0.5 cc according to the report by Stamy et al. (Cancer 71:933-938, 1993) was detected in 9 (29.0%) in group A and 170 (88.1%) in group B. Mean age in group A was significantly older than that in group B, while despite the lack of significant difference in the incidence of seminal vesicle invasion between these two groups, other parameters in group A were significantly more favorable than those in group B, including serum prostate-specific antigen, pathological stage, Gleason score, perineural invasion and capsular penetration. None of the patients in group A had biochemical recurrence (median observation period, 82 months); however, biochemical recurrence occurred in 41 (21.2%) in group B (median observation period, 46 months). Furthermore, immunohistochemical study demonstrated the significantly greater expression of Ki-67, p53 and AR proteins in group B than in group A.
  
  
  CONCLUSIONS
  Clinicopathological features of incidentally detected prostate cancer are markedly more favorable than those of clinically detected prostate cancer, which may reflect less aggressive biological phenotypes of incidental prostate cancer arising in Japanese men.
authors.affiliation: Division of Urology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Kurahashi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Miyake
authors.forename: Junya
authors.initials: J
authors.lastname: Furukawa
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kumano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takenaka
authors.forename: Masato
authors.initials: M
authors.lastname: Fujisawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015653:Cystectomy; D006801:Humans; D033162:Incidental Findings; D007564:Japan; D008297:Male; D008875:Middle Aged; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000453:epidemiology / Q000473:pathology*; D012189:Retrospective Studies; D001749:Urinary Bladder Neoplasms / Q000601:surgery*