title: Effect of delay in initiating radiotherapy for patients with early stage breast cancer.
abstract: OBJECTIVE
  For early stage breast cancer, a standard treatment option is partial mastectomy followed by radiation treatment. The 5-year risk of local recurrence ranges from 6-9%. Variable waiting times for radiation treatment of breast cancer in our institution provided an opportunity to evaluate the impact of waiting time on the risk of local recurrence.
  
  
  METHODS
  Between January 1988 and December 1989, 482 patients with stage I and II breast cancer were treated with radiotherapy in our institution. Information on prognostic factors, such as age, tumour size, histological grade, number of positive lymph nodes and margins of resection, was abstracted from their charts. The interval between date of surgery and date of initial radiation treatment was noted. Dates of local recurrence, metastasis and deaths were recorded.
  
  
  RESULTS
  At 5 years, the local recurrence rate was 8%, the metastatic rate 12% and the 'cause-specific' survival rate 90%. In univariate analysis, the risk of local recurrence was associated with younger age, higher histological grade and time to radiation treatment. In the multivariate analysis, the effect of time to radiation treatment on the risk of local recurrence was equivocal.
  
  
  CONCLUSIONS
  Delay in radiation treatment may be associated with an increased risk of local recurrence of breast cancer, at least in our centre. Future research is needed on a larger data set to more accurately estimate the effect of time to radiation treatment on the risk of local recurrence.
authors.affiliation: Department of Radiation Oncology, McGill University Health Centre, McGill University, Montreal, Canada. veronique.benk@tsrcc.on.ca
authors.forename: V
authors.initials: V
authors.lastname: Benk
authors.forename: L
authors.initials: L
authors.lastname: Joseph
authors.forename: P
authors.initials: P
authors.lastname: Fortin
authors.forename: G
authors.initials: G
authors.lastname: Zhang
authors.forename: P
authors.initials: P
authors.lastname: Belisle
authors.forename: C
authors.initials: C
authors.lastname: Levinton
authors.forename: V
authors.initials: V
authors.lastname: Ho
authors.forename: C R
authors.initials: CR
authors.lastname: Freeman
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012307:Risk Factors; D013997:Time Factors