title: Factors associated with the frequency of initial total mastectomy: results of a multi-institutional study.
abstract: BACKGROUND
  Several previous studies have reported conflicting data on recent trends in use of initial total mastectomy (TM); the factors that contribute to TM variation are not entirely clear. Using a multi-institution database, we analyzed how practice, patient, and tumor characteristics contributed to variation in TM for invasive breast cancer.
  
  
  METHODS
  We collected detailed clinical and pathologic data about breast cancer diagnosis, initial, and subsequent breast cancer operations performed on all female patients from 4 participating institutions from 2003 to 2008. We limited this analysis to 2,384 incident cases of invasive breast cancer, stages I to III, and excluded patients with clinical indications for mastectomy. Predictors of initial TM were identified with univariate analyses and random effects multivariable logistic regression models.
  
  
  RESULTS
  Initial TM was performed on 397 (16.7%) eligible patients. Use of preoperative MRI more than doubled the rate of TM (odds ratio [OR] = 2.44; 95% CI, 1.58-3.77; p < 0.0001). Increasing tumor size, high nuclear grade, and age were also associated with increased rates of initial TM. Differences by age and ethnicity were observed, and significant variation in the frequency of TM was seen at the individual surgeon level (p < 0.001). Our results were similar when restricted to tumors <20 mm.
  
  
  CONCLUSIONS
  We identified factors associated with initial TM, including preoperative MRI and individual surgeon, that contribute to the current debate about variation in use of TM for the management of breast cancer. Additional evaluation of patient understanding of surgical options and outcomes in breast cancer and the impact of the surgeon provider is warranted.
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado, Denver, CO 80237-8066, USA. heather.s.feigelson@kp.org
authors.forename: Heather Spencer
authors.initials: HS
authors.lastname: Feigelson
authors.forename: Ted A
authors.initials: TA
authors.lastname: James
authors.forename: Richard M
authors.initials: RM
authors.lastname: Single
authors.forename: Adedayo A
authors.initials: AA
authors.lastname: Onitilo
authors.forename: Erin J
authors.initials: EJ
authors.lastname: Aiello Bowles
authors.forename: Tom
authors.initials: T
authors.lastname: Barney
authors.forename: Jordan E
authors.initials: JE
authors.lastname: Bakerman
authors.forename: Laurence E
authors.initials: LE
authors.lastname: McCahill
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D015413:Mastectomy, Simple / Q000706:statistics & numerical data*; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D016017:Odds Ratio; D012307:Risk Factors; D014481:United States / Q000453:epidemiology