title: Evaluating the utility of a preoperative nomogram for predicting 90-day mortality following radical cystectomy for bladder cancer.
abstract: OBJECTIVE
  To evaluate the performance of the Isbarn nomogram for predicting 90-day mortality following radical cystectomy in a contemporary series.
  
  
  METHODS
  We identified 1141 consecutive radical cystectomy patients treated at our institution between 1995 and 2005 with at least 90 days of follow-up. We applied the published nomogram to our cohort, determining its discrimination, with the area under the receiver operating characteristic curve (AUC), and calibration. We further compared it with a simple model using age and the Charlson comorbidity score.
  
  
  RESULTS
  Our cohort was similar to that used to develop the Isbarn nomogram in terms of age, gender, grade and histology; however, we observed a higher organ-confined (≤pT2, N0) rate (52% vs 24%) and a lower overall 90-day mortality rate [2.8% (95% confidence interval 1.9%, 3.9%) vs 3.9%]. The Isbarn nomogram predicted individual 90-day mortality in our cohort with moderate discrimination [AUC 73.8% (95% confidence interval 64.4%, 83.2%)]. In comparison, a model using age and Charlson score alone had a bootstrap-corrected AUC of 70.2% (95% confidence interval 67.2%, 75.4%).
  
  
  CONCLUSIONS
  The Isbarn nomogram showed moderate discrimination in our cohort; however, the exclusion of important preoperative comorbidity variables and the use of postoperative pathological stage limit its utility in the preoperative setting. The use of a simple model combining age and Charlson score yielded similar discriminatory ability and underscores the significance of individual patient variables in predicting outcomes. An accurate tool for predicting postoperative morbidity/mortality following radical cystectomy would be valuable for treatment planning and counselling. Future nomogram design should be based on preoperative variables including individual risk factors, such as comorbidities.
authors: Department of Urology and Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA. taylorj3@mskcc.org
authors: Jennifer M
authors: JM
authors: Taylor
authors: Andrew
authors: A
authors: Feifer
authors: Caroline J
authors: CJ
authors: Savage
authors: Alexandra C
authors: AC
authors: Maschino
authors: Melanie
authors: M
authors: Bernstein
authors: Harry W
authors: HW
authors: Herr
authors: S Machele
authors: SM
authors: Donat
mesh_terms: D000368:Aged; D015653:Cystectomy / Q000379:methods / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D049451:Nomograms; D012372:ROC Curve; D018570:Risk Assessment / Q000379:methods / Q000592:standards; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000401:mortality* / Q000601:surgery