title: A pilot study of wider use of accelerated partial breast irradiation: intraoperative margin-directed re-excision combined with sole high-dose-rate interstitial brachytherapy.
abstract: BACKGROUND
  Accelerated partial breast irradiation (APBI) is generally limited to patients at extremely low risk of local recurrence. The significance of the risk factors, however, depends on the extent of surgery, radiation, and systemic therapy. In Japan, wide excision is generally supplemented by intraoperative margin-directed re-excision if the frozen section examination yields positive results. This approach combined with conventional radiotherapy achieved an excellent 10-year local control rate of 93%, and young age and ductal carcinoma in situ were not risk factors for local recurrence. To reduce the treatment duration, high-dose-rate interstitial brachytherapy (HDRIB) was employed. The first APBI phase I / II trial in Japan was conducted to determine if wider indications for early breast cancer patients were appropriate.
  
  
  METHODS
  The subjects comprised 20 patients including those with extensive intraductal component (n=7), ductal carcinoma in situ (n=2), positive final margins (n=3), and of younger age (< or = 45 years; n=5). Breast-conserving surgery using an intraoperative re-excision approach was followed by intraoperative implantation of applicators. Sole HDRIB of a 36-42 Gy in 6-7 fractions was delivered postoperatively over 3-4 days. Tumors were staged as follows: cT1 (n=12), cT2 (n=8), cN0 (n=20). Systemic therapy was used in 16 patients (80%). The median follow-up period was 52 months (range, 26-86 months).
  
  
  RESULTS
  Te five-year crude local, distant control, and Kaplan-Meier cause-specific survival rates were 95%, 95%, and 89%, respectively. Fat necrosis developed in 1 patient.
  
  
  CONCLUSIONS
  Sole HDRIB with intraoperative margin-directed re-excision was feasible under wider indications compared to other contemporary APBI series, and achieved acceptable and similar results to these series in terms of the local control rate and complications.
authors.affiliation: Department of Radiation Oncology, Cancer Institute Hospital, 3-10-6 Ariake, Koto-Ku, Tokyo 135-8550, Japan. takayuki.nose@jfcr.or.jp
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nose
authors.forename: Yoshihumi
authors.initials: Y
authors.lastname: Komoike
authors.forename: Ken
authors.initials: K
authors.lastname: Yoshida
authors.forename: Masahiko
authors.initials: M
authors.lastname: Koizumi
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Motomura
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kasugai
authors.forename: Hideo
authors.initials: H
authors.lastname: Inaji
authors.forename: Kinji
authors.initials: K
authors.lastname: Nishiyama
authors.forename: Hiroki
authors.initials: H
authors.lastname: Koyama
authors.forename: Takuyo
authors.initials: T
authors.lastname: Kozuka
authors.forename: Kotaro
authors.initials: K
authors.lastname: Gomi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Oguchi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Akahashi
authors.forename: Iori
authors.initials: I
authors.lastname: Sumida
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamashita
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy; D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D044584:Carcinoma, Ductal / Q000532:radiotherapy / Q000601:surgery; D018275:Carcinoma, Lobular / Q000532:radiotherapy / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D010865:Pilot Projects