title: Prognostic factors for urachal cancer: a bayesian model-averaging approach.
abstract: OBJECTIVE
  This study was conducted to evaluate prognostic factors and cancer-specific survival (CSS) in a cohort of 41 patients with urachal carcinoma by use of a Bayesian model-averaging approach.
  
  
  METHODS
  Our cohort included 41 patients with urachal carcinoma who underwent extended partial cystectomy, total cystectomy, transurethral resection, chemotherapy, or radiotherapy at a single institute. All patients were classified by both the Sheldon and the Mayo staging systems according to histopathologic reports and preoperative radiologic findings. Kaplan-Meier survival curves and Cox proportional-hazards regression models were carried out to investigate prognostic factors, and a Bayesian model-averaging approach was performed to confirm the significance of each variable by using posterior probabilities.
  
  
  RESULTS
  The mean age of the patients was 49.88 ± 13.80 years and the male-to-female ratio was 24:17. The median follow-up was 5.42 years (interquartile range, 2.8-8.4 years). Five- and 10-year CSS rates were 55.9% and 43.4%, respectively. Lower Sheldon (p=0.004) and Mayo (p<0.001) stage, mucinous adenocarcinoma (p=0.005), and larger tumor size (p=0.023) were significant predictors of high survival probability on the basis of a log-rank test. By use of the Bayesian model-averaging approach, higher Mayo stage and larger tumor size were significant predictors of cancer-specific mortality in urachal carcinoma.
  
  
  CONCLUSIONS
  The Mayo staging system might be more effective than the Sheldon staging system. In addition, the multivariate analyses suggested that tumor size may be a prognostic factor for urachal carcinoma.
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: In Kyong
authors.initials: IK
authors.lastname: Kim
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Joo Yong
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jong Kyou
authors.initials: JK
authors.lastname: Kwon
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae Joon
authors.initials: JJ
authors.lastname: Park
authors.affiliation: Department of Urology, Gangnam Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kang Su
authors.initials: KS
authors.lastname: Cho
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Won Sik
authors.initials: WS
authors.lastname: Ham
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Joon
authors.initials: SJ
authors.lastname: Hong
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seung Choul
authors.initials: SC
authors.lastname: Yang
authors.affiliation: Department of Urology, Severance Hospital, Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea. ; Robot and Minimal Invasive Surgery Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Deuk
authors.initials: YD
authors.lastname: Choi
mesh_terms: D000328:Adult; D001499:Bayes Theorem; D002277:Carcinoma / Q000473:pathology* / Q000628:therapy*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000473:pathology* / Q000628:therapy*
keywords: Follow-up studies; Survival; Urachal cancer