title: Rates of breast cancer surgery in Canada from 2007/08 to 2009/10: retrospective cohort study.
abstract: BACKGROUND
  Surgery is a common and important component of breast cancer treatment. We assessed the rates of breast cancer surgery across Canada from 2007/08 to 2009/10.
  
  
  METHODS
  We used hospital and day surgery data from the Canadian Institute for Health Information to assemble a cohort of women who had undergone breast cancer surgery. We identified the index surgical procedure and subsequent surgical procedures performed within 1 year for each woman included in the analysis. We calculated the crude mastectomy rate for each province, and we calculated the adjusted mastectomy rate for select jurisdictions using a logistic regression model fitted using age, neighbourhood income quintile and travel time.
  
  
  RESULTS
  In total, 57 840 women underwent breast cancer surgery during the study period. Among women with unilateral invasive breast cancer, the crude mastectomy rate was 39%. Adjusted rates for mastectomy varied widely by province (26%-69%). The rate of re-excision within 1 year for women who had breast-conserving surgery as their index procedure was 23% and varied by province in terms of frequency and type (mastectomy or repeat breast-conserving surgery). Among women who underwent mastectomy for unilateral invasive breast cancer, 6% also underwent contralateral prophylactic mastectomy, and 7% had immediate breast reconstruction following surgery. Of mastectomy procedures, 20% were performed as day surgery; for breast-conserving surgery, 70% were performed as day surgery.
  
  
  CONCLUSIONS
  There is substantial interprovincial variation in surgical care for breast cancer in Canada. Further research is needed to better understand such variation, and continued monitoring should be the focus of quality initiatives.
authors: Surgical Oncology, Dalhousie University, Halifax NS.
authors: Geoff
authors: G
authors: Porter
authors: Canadian Institute for Health Information, Ottawa, Ont. ; School of Health Information Science, University of Victoria, Victoria, BC.
authors: Brandon
authors: B
authors: Wagar
authors: Cancer Control, Canadian Partnership Against Cancer, Toronto, Ont.
authors: Heather
authors: H
authors: Bryant
authors: Canadian Institute for Health Information, Ottawa, Ont.
authors: Maria
authors: M
authors: Hewitt
authors: Faculty of Medicine, University of British Columbia, Vancouver BC, ; BC Cancer Agency (BCCA) - Vancouver Island Centre, Victoria, BC.
authors: Elaine
authors: E
authors: Wai
authors: Division of General Surgery, University of Alberta, Edmonton, Alta.
authors: Kelly
authors: K
authors: Dabbs
authors: Western Canada and Development Initiatives, Canadian Institute for Health Information, Ottawa, Ont.
authors: Anne
authors: A
authors: McFarlane
authors: System Performance and Surveillance, Canadian Partnership Against Cancer, Toronto, Ont.
authors: Rami
authors: R
authors: Rahal