title: Electronic brachytherapy as adjuvant therapy for early stage breast cancer: a retrospective analysis.
abstract: OBJECTIVE
  This multicenter, retrospective study evaluated treatment and clinical outcomes of patients with early stage breast cancer who received adjuvant high-dose rate (HDR) electronic brachytherapy (EBT) treatment post-lumpectomy using the Axxent(®) EBT system. Dosimetric data from the EBT treatment plans were compared with those based on iridium-192 HDR brachytherapy.
  
  
  METHODS
  Medical records of 63 patients with early stage breast cancer (Tis, T1a, T1b, T1c, and T2) who were treated post-lumpectomy with EBT alone or in combination with external beam radiation therapy were reviewed. The prescribed EBT dose was 34 Gy (10 fractions over 5 days, 3.4 Gy each) to 1 cm from the balloon surface. Dosimetry data from 12 patients were compared with these of treatment plans using an iridium-192 source prepared for the same 12 patients.
  
  
  RESULTS
  The majority of patients (90.5%) were older than 50 years and had one or more risk factors for breast cancer (80.6%). Tumor sizes were 0.1 cm to 3.5 cm (mean 1.3 cm). Median follow-up was 7 months (1 to 18 months) post-EBT. Balloon applicators were implanted 0 to 85 days (mean 13.4 days) post-lumpectomy/re-excision. The most common adverse events were erythema, rash dermatitis, and pain or breast tenderness. No recurrences were reported. Dosimetric analyses demonstrated comparable target coverage, increased high-dose regions, and a significantly reduced dose to the ipsilateral breast and lungs as well as the heart with EBT as compared with the iridium-192 treatment plans.
  
  
  CONCLUSIONS
  This retrospective, multicenter study showed that postsurgical adjuvant radiation therapy for early stage breast cancer can be administered using the EBT system with similar toxicity outcomes to those reported with iridium-192 brachytherapy. EBT offers a convenient, portable, nonisotope alternative to HDR brachytherapy using iridium-192.
authors.affiliation: Oklahoma University Health Sciences Center, Oklahoma City, OK, USA;
authors.forename: William C
authors.initials: WC
authors.lastname: Dooley
authors.forename: James C
authors.initials: JC
authors.lastname: Wurzer
authors.forename: Mohamed
authors.initials: M
authors.lastname: Megahy
authors.forename: Gary
authors.initials: G
authors.lastname: Schreiber
authors.forename: Tapan
authors.initials: T
authors.lastname: Roy
authors.forename: Gary
authors.initials: G
authors.lastname: Proulx
authors.forename: Susan
authors.initials: S
authors.lastname: Laduzinsky
authors.forename: Steven
authors.initials: S
authors.lastname: Lane
authors.forename: James
authors.initials: J
authors.lastname: Dalzell
authors.forename: Kambiz
authors.initials: K
authors.lastname: Dowlatshahi
authors.forename: Dwelvin
authors.initials: D
authors.lastname: Simmons
authors.forename: John P
authors.initials: JP
authors.lastname: Thropay
authors.forename: Harish
authors.initials: H
authors.lastname: Ahuja
authors.forename: Peter
authors.initials: P
authors.lastname: Beitsch
authors.forename: Randall W
authors.initials: RW
authors.lastname: Holt
authors.forename: Charles A
authors.initials: CA
authors.lastname: Lee