title: Influence of body mass index on operability, morbidity and disease outcome following radical cystectomy.
abstract: BACKGROUND
  Obesity may influence postoperative outcome after tumor surgery. We evaluated the impact of patients' body mass index (BMI) on peri- and postoperative morbidity and outcome following radical cystectomy for bladder cancer.
  
  
  METHODS
  390 consecutive patients who underwent radical cystectomy due to bladder cancer from January 1986 to December 2004 were reviewed. According to WHO criteria, patients were divided into normal weight (NW, 45.6%), overweight (OW, 44.4%) and obese (10.0%) subgroups. The BMI of patients was associated to the time of surgery, amount of intraoperative blood units, TNM stage, postoperative complication rate as well as overall survival.
  
  
  RESULTS
  The time of cystectomy increased with the degree of patients' obesity (NW, 330 min; OW, 355 min; p = 0.007). Between NW and OW patients no significant differences were noted in respect to intraoperative blood transfusion rate (NW, 3.0; OW, 2.0; p = 0.47), postoperative TNM stage (pTis-pT2b: 42.6 vs. 48.6%; pT3a-4: 38.2 vs. 27.2%; pN+: 20.2 vs. 24.2%) and postoperative complications, except for postoperative bleeding, which was more common in OW patients (p = 0.02). Mean overall survival times showed no significant differences between NW and OW patients receiving ileal conduits (5-year survival rate: 34.0 vs. 41.1%; p = 0.140) or ileal neobladders (5-year survival rate: 65.1 vs. 70.8%; p = 0.127).
  
  
  CONCLUSIONS
  Increased BMI poses a greater challenge for surgical interventions such as radical cystectomy in bladder cancer patients. However, in our series, intra- and postoperative morbidity was not significantly elevated in OW patients. Overall survival was not reduced in OW compared to NW patients. Therefore, elevated BMI is not an exclusion criterion for radical cystectomy in bladder cancer patients.
authors.affiliation: Department of Urology, Technical University of Munich, Klinikum rechts der Isar, Munchen, Germany. t.maurer@lrz.tum.de
authors.forename: Tobias
authors.initials: T
authors.lastname: Maurer
authors.forename: Jean
authors.initials: J
authors.lastname: Maurer
authors.forename: Margitta
authors.initials: M
authors.lastname: Retz
authors.forename: Roger
authors.initials: R
authors.lastname: Paul
authors.forename: Niko
authors.initials: N
authors.lastname: Zantl
authors.forename: Jurgen E
authors.initials: JE
authors.lastname: Gschwend
authors.forename: Uwe
authors.initials: U
authors.lastname: Treiber
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015653:Cystectomy / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology*; D012189:Retrospective Studies; D015996:Survival Rate; D001749:Urinary Bladder Neoplasms / Q000601:surgery*