title: Age at diagnosis predicts local recurrence in women treated with breast-conserving surgery and postoperative radiation therapy for ductal carcinoma in situ: a population-based outcomes analysis.
abstract: OBJECTIVE
  The main goal of treating ductal carcinoma in situ (dcis) is to prevent the development of invasive breast cancer. Most women are treated with breast-conserving surgery (bcs) and radiotherapy. Age at diagnosis may be a risk factor for recurrence, leading to concerns that additional treatment may be necessary for younger women. We report a population-based study of women with dcis treated with bcs and radiotherapy and an evaluation of the effect of age on local recurrence (lr).
  
  
  METHODS
  All women diagnosed with dcis in Ontario from 1994 to 2003 were identified. Treatments and outcomes were collected through administrative databases and validated by chart review. Women treated with bcs and radiotherapy were included. Survival analyses were performed to evaluate the effect of age on outcomes.
  
  
  RESULTS
  We identified 5752 cases of dcis; 1607 women received bcs and radiotherapy. The median follow-up was 10.0 years. The 10-year cumulative lr rate was 27% for women younger than 45 years, 14% for women 45-50 years, and 11% for women more than 50 years of age (p < 0.0001). The 10-year cumulative invasive lr rate was 22% for women younger than 45 years, 10% for women 45-50 years, and 7% for women more than 50 years of age (p < 0.0001). On multivariate analyses, young age (<45 years) was significantly associated with lr and invasive lr [hazard ratio (hr) for lr: 2.6; 95% confidence interval (ci): 1.9 to 3.7; p < 0.0001; hr for invasive lr: 3.0; 95% ci: 2.0 to 4.4; p < 0.0001]. An age of 45-50 years was also significantly associated with invasive lr (hr: 1.6; 95% ci: 1.0 to 2.4; p = 0.04).
  
  
  CONCLUSIONS
  Age at diagnosis is a strong predictor of lr in women with dcis after treatment with bcs and radiotherapy.
authors: Department of Radiation Oncology, Women's College Research Institute, Toronto, ON. ; Sunnybrook Health Sciences Centre, Toronto, ON. ; University of Toronto, Toronto, ON.
authors: I
authors: I
authors: Kong
authors: University of Toronto, Toronto, ON. ; Women's College Research Institute, Toronto, ON.
authors: S A
authors: SA
authors: Narod
authors: Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Centre, Toronto, ON.
authors: C
authors: C
authors: Taylor
authors: Department of Radiation Oncology, Women's College Research Institute, Toronto, ON. ; Sunnybrook Health Sciences Centre, Toronto, ON. ; University of Toronto, Toronto, ON. ; Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Centre, Toronto, ON.
authors: L
authors: L
authors: Paszat
authors: Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Centre, Toronto, ON.
authors: R
authors: R
authors: Saskin
authors: University of Toronto, Toronto, ON. ; Department of Pathology, University of Toronto, Toronto, ON.
authors: S
authors: S
authors: Nofech-Moses
authors: Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Centre, Toronto, ON.
authors: D
authors: D
authors: Thiruchelvam
authors: University of Toronto, Toronto, ON. ; Department of Pathology, University of Toronto, Toronto, ON.
authors: W
authors: W
authors: Hanna
authors: Department of Radiation Oncology, Women's College Research Institute, Toronto, ON. ; Sunnybrook Health Sciences Centre, Toronto, ON. ; University of Toronto, Toronto, ON.
authors: J P
authors: JP
authors: Pignol
authors: Department of Pathology, University of Toronto, Toronto, ON. ; Kingston General Hospital, Kingston, ON.
authors: S
authors: S
authors: Sengupta
authors: Department of Pathology, University of Toronto, Toronto, ON. ; Henderson General Hospital, Hamilton, ON.
authors: L
authors: L
authors: Elavathil
authors: Department of Pathology, University of Toronto, Toronto, ON. ; Thunder Bay Regional Health Sciences Centre, Thunder Bay, ON.
authors: P A
authors: PA
authors: Jani
authors: Campbell Family Institute for Breast Cancer Research, University Health Network, Toronto, ON.
authors: S J
authors: SJ
authors: Done
authors: Sunnybrook Health Sciences Centre, Toronto, ON.
authors: S
authors: S
authors: Metcalfe
authors: Department of Radiation Oncology, Women's College Research Institute, Toronto, ON. ; Sunnybrook Health Sciences Centre, Toronto, ON. ; Institute for Clinical Evaluative Sciences, Sunnybrook Health Sciences Centre, Toronto, ON. ; University of Toronto, Toronto, ON.
authors: E
authors: E
authors: Rakovitch
keywords: Ductal carcinoma in situ; age; radiation; recurrence; young patients