title: Factors Influencing Selection of Active Surveillance for Localized Prostate Cancer.
abstract: OBJECTIVE
  To determine how well demographic and clinical factors predict the initiation of Active Surveillance (AS).
  
  
  METHODS
  AS has been suggested as a way to reduce overtreatment of men who have prostate cancer; however, factors associated with the decision to choose AS are poorly quantified. Using the Michigan Urological Surgery Improvement Collaborative registry, we identified 2977 men with prostate cancer who made treatment decisions from January 1, 2012, through December 31, 2013. We used chi-square and Wilcoxon tests to examine the association between factors and initiation of AS. Logistic regression models were fit for D'Amico risk categories. Measures of model discrimination and calibration were estimated, including area under the curve (AUC) and Brier score (BS).
  
  
  RESULTS
  Patient age, Gleason score, clinical T-stage, urology practice, and tumor volume (greatest percent of a core involved with cancer and proportion of positive cores) were associated with the decision to choose AS in the intermediate-risk cohort (AUC = 0.875, BS = 0.07) and the complete cohort (AUC = 0.89, BS = 0.10). Patient age, urology practice, and tumor volume were significant in the low-risk cohort (AUC = 0.71, BS = 0.22). The addition of urology practice increased AUC in the low-risk cohort from 0.71 to 0.76 and reduced BS from 0.22 to 0.21.
  
  
  CONCLUSIONS
  The urology practice at which a patient is seen is an important predictor for whether patients will initiate AS. Predictions were least accurate for low-risk patients, suggesting that factors such as patient preference play a role in treatment decisions.
authors.affiliation: Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, MI.
authors.forename: Jianyu
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Urology, University of Michigan, Ann Arbor, MI.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Womble
authors.affiliation: Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, MI.
authors.forename: Selin
authors.initials: S
authors.lastname: Merdan
authors.affiliation: Department of Urology, University of Michigan, Ann Arbor, MI.
authors.forename: David C
authors.initials: DC
authors.lastname: Miller
authors.affiliation: Department of Urology, University of Michigan, Ann Arbor, MI.
authors.forename: James E
authors.initials: JE
authors.lastname: Montie
authors.affiliation: Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, MI; Department of Urology, University of Michigan, Ann Arbor, MI. Electronic address: btdenton@umich.edu.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Denton
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D016009:Chi-Square Distribution; D015331:Cohort Studies; D006801:Humans; D007150:Immunohistochemistry; D016015:Logistic Models; D008297:Male; D008824:Michigan; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D057240:Patient Preference / Q000706:statistics & numerical data; D018579:Patient Selection; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy / Q000706:statistics & numerical data; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D015996:Survival Rate; D014481:United States; D057832:Watchful Waiting / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D017430:Prostate-Specific Antigen