title: Technical factors, surgeon case volume and positive margin rates after breast conservation surgery for early-stage breast cancer.
abstract: BACKGROUND
  For patients with breast cancer, a negative surgical margin at first breast-conserving surgery (BCS) minimizes the need for reoperation and likely reduces postoperative anxiety. We assessed technical factors, surgeon and hospital case volume and margin status after BCS in early-stage breast cancer.
  
  
  METHODS
  We performed a retrospective cohort study using a regional cancer centre database of patients who underwent BCS for breast cancer from 2000 to 2002. We considered the influence of patient, tumour and technical factors (e.g., size of specimen and preoperative diagnosis of cancer available) and surgeon and hospital case volume on margin status at first and final operation. We performed univariate and multivariate regression analyses.
  
  
  RESULTS
  We reviewed 489 cases. There were no differences in patient or tumour characteristics among the low-, medium- and high-volume surgeon groups. High-volume surgeons were significantly more likely than other surgeons to operate with a confirmed preoperative diagnosis and to resect a larger volume of tissue. In our univariate analysis and at first operation, the rates of positive margins were 16.4%, 32.9% and 29.1% for high-, medium- and low-volume surgeons, respectively (p = 0.002). In the multivariate analysis, tumour factors (palpability, size, histology), presence of a confirmed preoperative diagnosis and size of resection specimen significantly predicted negative margins. However, when we controlled for these and other factors, high surgeon volume was not a predictor of negative margins at first surgery (odds ratio 1.8, 95% confidence interval 0.9-3.8, p = 0.09). Increased hospital volume was not associated with a lower rate of positive margins at first surgery.
  
  
  CONCLUSIONS
  Various tumour and technical factors were associated with negative margins at first BCS, whereas surgeon and hospital volume status were not. Technical steps that are under the control of the operating surgeon are likely effective targets for quality initiatives in breast cancer surgery.
authors.affiliation: Department of Surgery, McMaster University, Hamilton, Ontario, Canada. lovricsp@mcmaster.ca
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lovrics
authors.forename: Sylvie D
authors.initials: SD
authors.lastname: Cornacchi
authors.forename: Forough
authors.initials: F
authors.lastname: Farrokhyar
authors.forename: Anna
authors.initials: A
authors.lastname: Garnett
authors.forename: Vicky
authors.initials: V
authors.lastname: Chen
authors.forename: Slobodan
authors.initials: S
authors.lastname: Franic
authors.forename: Marko
authors.initials: M
authors.lastname: Simunovic
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology / Q000601:surgery; D018275:Carcinoma, Lobular / Q000473:pathology / Q000601:surgery; D015331:Cohort Studies; D042241:Early Diagnosis; D005260:Female; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009864:Ontario; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D016526:Workload / Q000706:statistics & numerical data*