title: Incidence and location of lymph node metastases in patients undergoing radical cystectomy for clinical non-muscle invasive bladder cancer: results from a prospective lymph node mapping study.
abstract: OBJECTIVE
  The objective of this study is to investigate the incidence and location of lymph node metastases (LNMs) in patients undergoing radical cystectomy (RC) and lymph node dissection (LND) for clinical non-muscle invasive bladder cancer (NMIBC).
  
  
  METHODS
  Prospectively collected data of 637 patients who underwent RC and 'superextended' LND with intent-to-cure for urothelial carcinoma of the bladder between 2002 and 2008 were examined. Inclusion criteria were (a) clinical stage Ta, Tis-only, or T1, (b) muscle presence at diagnostic transurethral resection in clinical T1 patients, (c) no prior diagnosis of ≥ T2 disease, (d) no neoadjuvant therapy, and (e) lymphatic tissue sample submitted from all 13 predesignated locations. Lymph node mapping was performed in all patients to determine the location of metastatic lymph nodes. Median follow-up time was 4.7 years. Recurrence-free survival and overall survival were reported.
  
  
  RESULTS
  A total of 114 patients were included of whom 9 patients (7.9%) had LNM. Stratified by clinical stage, LNM was present in 6/67 (9.0%) patients with cT1, 3/25 (12.0%) patients with cTis-only, and none of the 22 patients with cTa. Of the 9 node-positive patients (33.3%), 3 had LNM proximal to the aortic bifurcation. No skip metastases were found. After RC, 27 patients (23.7%) were upstaged to muscle invasive disease; of whom 16.7% had cT1, 2.6% had cTa, and 4.4% had cTis-only. Of the remaining 87 patients with pathologic NMIBC, 1 patient (1.1%) had LNM, limited to the true pelvis. Five-year RFS was 82.3%, 81.5%, and 62.0% in patients with pathologic NMIBC, clinical NMIBC, and pathologic muscle invasive bladder cancer, respectively.
  
  
  CONCLUSIONS
  Routine LND is important in patients with cT1 and cTis-only bladder cancer, but may have limited value in patients with cTa. LNM beyond the boundaries of a standard LND occurred in up to one-third of node-positive patients. In the absence of skip metastases, however, performing a standard LND would correctly identify all node-positive patients. Whether removal of LNM proximal to the common iliac vessels provides a survival benefit remains to be evaluated in future prospective studies.
authors: Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands.
authors: Harman M
authors: HM
authors: Bruins
authors: Department of Urology, Stanford University, Stanford, CA.
authors: Eila C
authors: EC
authors: Skinner
authors: Institute of Urology, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA.
authors: Ryan P
authors: RP
authors: Dorin
authors: Institute of Urology, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA.
authors: Hamed
authors: H
authors: Ahmadi
authors: Institute of Urology, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA.
authors: Hooman
authors: H
authors: Djaladat
authors: Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands.
authors: Gus
authors: G
authors: Miranda
authors: Institute of Urology, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA.
authors: Jie
authors: J
authors: Cai
authors: Institute of Urology, USC/Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA. Electronic address: daneshma@usc.edu.
authors: Siamak
authors: S
authors: Daneshmand
mesh_terms: D000368:Aged; D015653:Cystectomy; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011446:Prospective Studies; D012008:Recurrence; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology / Q000473:pathology*
keywords: Bladder neoplasms; Lymphadenectomy; Radical cystectomy