title: Development of prognostic model for predicting survival after retrograde placement of ureteral stent in advanced gastrointestinal cancer patients and its evaluation by decision curve analysis.
abstract: BACKGROUND
  The aim of this study was to determine risk factors for survival after retrograde placement of ureteral stents and develop a prognostic model for advanced gastrointestinal tract (GIT: esophagus, stomach, colon and rectum) cancer patients.
  
  
  METHODS
  We examined the clinical records of 122 patients who underwent retrograde placement of a ureteral stent against malignant extrinsic ureteral obstruction. A prediction model for survival after stenting was developed. We compared its clinical usefulness with our previous model based on the results from nephrostomy cases by decision curve analysis.
  
  
  RESULTS
  Median follow-up period was 201 days (8-1490) and 97 deaths occurred. The 1-year survival rate in this cohort was 29%. Based on multivariate analysis, primary site of colon origin, absence of retroperitoneal lymph node metastasis and serum albumin >3g/dL were significantly associated with a prolonged survival time. To develop a prognostic model, we divided the patients into 3 risk groups of favorable: 0-1 factors (N.=53), intermediate: 2 risk factors (N.=54), and poor: 3 risk factors (N.=15). There were significant differences in the survival profiles of these 3 risk groups (P<0.0001). Decision curve analyses revealed that the current model has a superior net benefit than our previous model for most of the examined probabilities.
  
  
  CONCLUSIONS
  We have developed a novel prognostic model for GIT cancer patients who were treated with retrograde placement of a ureteral stent. The current model should help urologists and medical oncologists to predict survival in cases of malignant extrinsic ureteral obstruction.
authors.affiliation: Department of Colorectal Surgery, National Cancer Center Hospital East, Chiba, Japan - yokomai@east.ncc.go.jp.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kawano
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Komai
authors.forename: Junichiro
authors.initials: J
authors.lastname: Ishioka
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Sakai
authors.forename: Nozomu
authors.initials: N
authors.lastname: Fuse
authors.forename: Masaaki
authors.initials: M
authors.lastname: Ito
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kihara
authors.forename: Norio
authors.initials: N
authors.lastname: Saito
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000066491:Clinical Decision-Making; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000150:complications / Q000401:mortality / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents; D015996:Survival Rate; D014513:Ureter / Q000601:surgery*; D014517:Ureteral Obstruction / Q000209:etiology / Q000401:mortality* / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods