title: Assessing the clinical benefit of nuclear matrix protein 22 in the surveillance of patients with nonmuscle-invasive bladder cancer and negative cytology: a decision-curve analysis.
abstract: BACKGROUND
  Several studies have demonstrated that abnormal levels of nuclear matrix protein 22 (NMP22) are associated with bladder cancer and have led to the approval of NMP22 as a urinary biomarker by the US Food and Drug Administration. Nonetheless, the clinical significance of NMP22 remains unclear. The objective of this study was to use decision analysis to determine whether NMP22 improves medical decision-making.
  
  
  METHODS
  The current study included 2222 patients who had a history of nonmuscle-invasive bladder cancer and current negative cytology. The authors developed models to predict cancer recurrence or progression to muscle-invasive disease using voided NMP22 levels, cystoscopy, age, and sex. Clinical net benefit was calculated by summing the benefits (true-positives), subtracting the harms (false-positives), and weighting these values by the threshold probability at which a patient or clinician would opt for cytoscopy.
  
  
  RESULTS
  After cystoscopy, 581 patients (26%) had cancer identified. The NMP22 level was associated significantly with bladder cancer recurrence and progression (P < .001 for both). The use of NMP22 in a model with age and sex was associated with better patient outcomes than performing cystoscopy on everyone and produced threshold probabilities > 8% for recurrence and > 3% for progression. Only offering cystoscopy to those who had a risk > 15% reduced the number of cystoscopies by 229 while missing only 25 cancer recurrences per 1000 men with negative cytology. The current study was limited by its multicenter design.
  
  
  CONCLUSIONS
  For clinicians who would perform a cystoscopy at a threshold of 5% for recurrence or 1% for progression, NMP22 did not aid clinical decision-making. For less risk-averse clinicians who would only perform a cystoscopy at a threshold probability >thinsp;8% for recurrence or > 3% for progression, NMP22 helped to indicate which patients required cystoscopy and which could be spared this procedure.
authors.affiliation: Department of Surgery (Urology), Memorial Sloan-Kettering Cancer Center, New York, New York, USA. sfshariat@gmail.com
authors.forename: Shahrokh F
authors.initials: SF
authors.lastname: Shariat
authors.forename: Caroline
authors.initials: C
authors.lastname: Savage
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Chromecki
authors.forename: Maxine
authors.initials: M
authors.lastname: Sun
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Scherr
authors.forename: Richard K
authors.initials: RK
authors.lastname: Lee
authors.forename: Giovanni
authors.initials: G
authors.lastname: Lughezzani
authors.forename: Mesut
authors.initials: M
authors.lastname: Remzi
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Marberger
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Vickers
mesh_terms: D000367:Age Factors; D000368:Aged; D014408:Biomarkers, Tumor / Q000652:urine*; D003558:Cystoscopy; D003661:Decision Support Techniques; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009687:Nuclear Proteins / Q000652:urine*; D011379:Prognosis; D012737:Sex Factors; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000652:urine
chemical_list: D014408:Biomarkers, Tumor; D009687:Nuclear Proteins; C100379:nuclear matrix protein 22