title: Role of pelvic lymph node dissection in lymph node-negative patients with invasive bladder cancer.
abstract: OBJECTIVE
  The role of pelvic lymphadenectomy in patients with lymph node-negative bladder cancer at radical cystectomy (RC) has not yet been examined in detail. We retrospectively reviewed patients who underwent RC with pelvic lymphadenectomy for bladder cancer from January 1987 to March 2008.
  
  
  METHODS
  We identified consecutive data on 169 patients who underwent RC for bladder cancer. The mean follow-up was 64 months (range: 1-253 months). Node-positive status (pN(+)) was seen in 16 patients and 91 were diagnosed as node-negative (pN(-)). The lymph node status of the remaining 62 patients was unclear (pN(x)). We analysed the association between lymph node status and cancer-specific survival (CSS), and examined the role of the number of retrieved lymph nodes, particularly in pN(-).
  
  
  RESULTS
  The median number of retrieved nodes was 12.9 and 10.2 for stage pN(+) and stage pN(-), respectively. In 91 patients with pN(-), multivariate analysis revealed that pathological T3-4 (P = 0.0276) and less than nine retrieved lymph nodes (P = 0.0108) were independent risk factors for CSS. In a subgroup of 83 patients with pT3-4, Kaplan-Meier curves showed that the 5-year CSS rate in pN(-) patients with less than nine retrieved lymph nodes was 38.8%, which was extremely similar to the 40.8% in pN(+) and 45.1% in pN(x).
  
  
  CONCLUSIONS
  Our results demonstrate that at least nine lymph nodes should be removed to improve the survival of pN(-) patients at RC and lymphadenectomy, and would provide information not only on prognosis but also on the therapeutic impact on pT3-4 invasive bladder cancer.
authors.affiliation: Department of Urology, Keio University School of Medicine, 35, Shinanomachi, Shinjuku-ku, Tokyo, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Shirotake
authors.forename: Eiji
authors.initials: E
authors.lastname: Kikuchi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yazawa
authors.forename: Takeo
authors.initials: T
authors.lastname: Kosaka
authors.forename: Akira
authors.initials: A
authors.lastname: Miyajima
authors.forename: Ken
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Oya
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015653:Cystectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010388:Pelvis; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000473:pathology / Q000601:surgery*