title: Stage, treatment and outcomes for patients with breast cancer in British Columbia in 2002: a population-based cohort study.
abstract: BACKGROUND
  There are very few long-term Canadian data on breast cancer outcomes by stage. We described the stage, treatment and outcomes of breast cancer at a population level for patients in British Columbia.
  
  
  METHODS
  This population-based cohort study included almost all patients with incident breast cancer registered in 2002 (about 97.6% registry case completeness). For these patients, information on stage, primary local surgery, radiotherapy, chemotherapy, hormone therapy and survival outcome (based on registry date and cause-of-death data) were available. We calculated Kaplan-Meier curves for breast cancer-specific survival and overall survival by stage and analyzed prognostic and treatment factors with a multivariable Cox model.
  
  
  RESULTS
  The 2927 incident cases of breast cancer identified in 2002 had the following distribution by stage: stage 0 (in situ), 424 (14%); stage I, 1118 (38%); stage II, 938 (32%); stage III, 233 (8%); stage IV, 123 (4%); unknown, 91 (3%). The distribution of patients' ages was < 40 years, 127 (4%); 40-49, 538 (18%); 50-59, 719 (25%); 60-69, 660 (23%); 70-79, 583 (20%); ≥ 80, 300 (10%). Within the first year after diagnosis, radiotherapy was provided to 1649 patients (56%), chemotherapy to 928 (32%) and hormone therapy to 1664 (57%). Ten-year breast cancer-specific survival rates by stage were > 99% for stage 0, 95% for stage I, 81% for stage II, 55% for stage III and 4% for stage IV. Ten-year overall survival rates were 89% for stage 0, 81% for stage I, 68% for stage II, 43% for stage III and 2% for stage IV.
  
  
  CONCLUSIONS
  This analysis provides a Canadian benchmark for treatment rates and 10-year outcomes by stage for all incident cases of breast cancer in a single province. Outcomes in British Columbia compared well with published rates for the United States and Europe.
authors: Department of Medical Oncology, Fraser Valley Centre, British Columbia Cancer Agency, Vancouver, BC.
authors: Ashley
authors: A
authors: Davidson
authors: Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC ; Department of Medical Oncology, Vancouver Centre, British Columbia Cancer Agency, Vancouver, BC.
authors: Stephen
authors: S
authors: Chia
authors: Department of Radiation Oncology, Centre for the North, British Columbia Cancer Agency, Vancouver, BC.
authors: Robert
authors: R
authors: Olson
authors: Department of Radiation Oncology, Vancouver Centre, British Columbia Cancer Agency, Vancouver, BC.
authors: Alan
authors: A
authors: Nichol
authors: Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC.
authors: Caroline
authors: C
authors: Speers
authors: Cancer Surveillance and Outcomes, British Columbia Cancer Agency, Vancouver, BC.
authors: Andy J
authors: AJ
authors: Coldman
authors: British Columbia Research Centre, British Columbia Cancer Agency, Vancouver, BC.
authors: Chris
authors: C
authors: Bajdik
authors: Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC.
authors: Ryan
authors: R
authors: Woods
authors: Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC ; Department of Radiation Oncology, Vancouver Centre, British Columbia Cancer Agency, Vancouver, BC.
authors: Scott
authors: S
authors: Tyldesley