title: Prospective study of local control and late radiation toxicity after intraoperative radiation therapy boost for early breast cancer.
abstract: OBJECTIVE
  To report the local recurrence rate and late toxicity of intraoperative radiation therapy (IORT) boost to the tumor bed using the Intrabeam System followed by external-beam whole-breast irradiation (WBI) in women with early-stage breast cancer in a prospective single-institution study.
  
  
  METHODS
  Women with breast cancer≤3 cm were recruited between February 2003 and May 2005. After breast-conserving surgery, a single dose of 5 Gy IORT boost was delivered using 50-kV x-rays to a depth of 10 mm from the applicator surface. This was followed by WBI to a total dose of 50 Gy in 25 fractions. Patients were reviewed at regular, predefined intervals. Late toxicities were recorded using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring systems.
  
  
  RESULTS
  Fifty-five patients completed both IORT boost and external-beam WBI. Median follow-up was 3.3 years (range, 1.4-4.1 years). There was no reported locoregional recurrence or death. One patient developed distant metastases. Grade 2 and 3 subcutaneous fibrosis was detected in 29 (53%) and 8 patients (15%), respectively.
  
  
  CONCLUSIONS
  The use of IORT as a tumor bed boost using kV x-rays in breast-conserving therapy was associated with good local control but a clinically significant rate of grade 2 and 3 subcutaneous fibrosis.
authors: Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia. Electronic address: David.Chang@petermac.org.
authors: David W
authors: DW
authors: Chang
authors: Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.
authors: Luc
authors: L
authors: te Marvelde
authors: Division of Radiation Oncology and Cancer Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia; Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria, Australia.
authors: Boon H
authors: BH
authors: Chua
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D005260:Female; D005355:Fibrosis; D005500:Follow-Up Studies; D006801:Humans; D007432:Intraoperative Period; D015412:Mastectomy, Segmental; D008875:Middle Aged; D011446:Prospective Studies; D011832:Radiation Injuries / Q000473:pathology*; D011855:Radiodermatitis / Q000473:pathology; D011879:Radiotherapy Dosage; D040521:Subcutaneous Tissue / Q000473:pathology / Q000528:radiation effects*; D047368:Tumor Burden