title: Three-dimensional conformal hypofractionated simultaneous integrated boost in breast conserving therapy: results on local control and survival.
abstract: OBJECTIVE
  To report on local control and survival after breast conserving therapy (BCT) including three-dimensional conformal simultaneous integrated boost irradiation (3D-CRT-SIB) and on the influence of age on outcome.
  
  
  METHODS
  For this study, 752 consecutive female breast cancer patients (stages I-III), treated with 3D-CRT-SIB at the University Medical Center Groningen from 2005 to 2008, were retrospectively identified. Median age was 58.4 (range 26-84) years. The SIB fractionation used was: 28×1.8Gy (whole breast) and 28×2.3Gy or 2.4Gy (tumour bed). Next to outcome, we estimated the effect of age on the recurrence-free period (RFP) by multivariate Cox regression survival analysis.
  
  
  RESULTS
  Median follow-up was 41 (range 3-65) months. Local control was 99.6% at 3 years (6 ipsilateral recurrences). The 3-year locoregional control, RFP and overall survival (OS) rates were 99.2%, 95.5%, and 97.1%, respectively. In multivariate analysis, tumours >2cm (hazard ratio (HR) 3.11; 95% confidence interval (CI) 1.57-6.17) and triple negativity (HR 3.03; 95% CI 1.37-6.67) and not age were associated with impaired RFP.
  
  
  CONCLUSIONS
  At 3 years, the 3D-CRT-SIB technique in BCT results in excellent local control and OS. Age was not a risk factor for any recurrence.
authors.affiliation: Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Enja J
authors.initials: EJ
authors.lastname: Bantema-Joppe
authors.forename: Hans Paul
authors.initials: HP
authors.lastname: van der Laan
authors.forename: Geertruida H
authors.initials: GH
authors.lastname: de Bock
authors.forename: Robin
authors.initials: R
authors.lastname: Wijsman
authors.forename: Wil V
authors.initials: WV
authors.lastname: Dolsma
authors.forename: Dianne M
authors.initials: DM
authors.lastname: Busz
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Langendijk
authors.forename: John H
authors.initials: JH
authors.lastname: Maduro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality / Q000628:therapy*; D003131:Combined Modality Therapy; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D015999:Multivariate Analysis; D016609:Neoplasms, Second Primary / Q000453:epidemiology; D020266:Radiotherapy, Conformal / Q000009:adverse effects / Q000379:methods*; D012189:Retrospective Studies; D017211:Treatment Failure