title: Obesity and prognosis in muscle-invasive bladder cancer: the continuing controversy.
abstract: OBJECTIVE
  To investigate the association between body mass index and clinicopathological features of bladder cancer, and to assess the prognostic value of body mass index in patients undergoing radical cystectomy for bladder cancer.
  
  
  METHODS
  The medical records of 714 patients who underwent radical cystectomy for bladder cancer were reviewed. The association of body mass index at surgery with clinicopathological features was examined, and the prognostic value of body mass index for recurrence-free survival and cancer-specific survival was analyzed using the Kaplan-Meier method and Cox regression models. Additional survival analyses were carried out in a subgroup of 534 patients with N0M0 disease.
  
  
  RESULTS
  Of 714 patients, 304 (42.6%), 184 (25.8%) and 226 (31.7%) had a body mass index of <23 (normal), 23-25 (overweight), and ≥25 (obese) kg/m(2) , respectively. Patients with high body mass index had a lower pathological T stage, fewer lymph node metastases and a lower frequency of lymphovascular invasion than those with low body mass index (P < 0.05). Multivariable analysis showed that obese status was an independent predictor of recurrence-free survival (obese vs normal: P < 0.001; overweight vs normal: P = 0.008) and cancer-specific survival (obese vs normal: P < 0.001; overweight vs normal: P = 0.019), along with pathological T stage, lymph node metastasis, and lymphovascular invasion. In addition, obesity was significantly associated with recurrence-free survival (P = 0.018) and cancer-specific survival (P = 0.019) in patients with N0M0 status.
  
  
  CONCLUSIONS
  The present findings suggest that overweight and obesity are associated with favorable pathological features and prognosis in patients with bladder cancer undergoing radical cystectomy.
authors.affiliation: Department of Urology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Taekmin
authors.initials: T
authors.lastname: Kwon
authors.forename: In Gab
authors.initials: IG
authors.lastname: Jeong
authors.forename: Dalsan
authors.initials: D
authors.lastname: You
authors.forename: Kyung-Sik
authors.initials: KS
authors.lastname: Han
authors.forename: Sungwoo
authors.initials: S
authors.lastname: Hong
authors.forename: Bumsik
authors.initials: B
authors.lastname: Hong
authors.forename: Jun Hyuk
authors.initials: JH
authors.lastname: Hong
authors.forename: Hanjong
authors.initials: H
authors.lastname: Ahn
authors.forename: Choung-Soo
authors.initials: CS
authors.lastname: Kim
mesh_terms: D000368:Aged; D015992:Body Mass Index; D002277:Carcinoma / Q000150:complications* / Q000473:pathology / Q000601:surgery; D015653:Cystectomy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D011379:Prognosis; D012189:Retrospective Studies; D001743:Urinary Bladder / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000150:complications* / Q000473:pathology / Q000601:surgery
keywords: body mass index; cystectomy; prognosis; urinary bladder neoplasm