title: A phase I study of intraoperative radiotherapy for early breast cancer in Japan.
abstract: BACKGROUND
  The present study was designed to identify the optimal intraoperative radiotherapy (IORT) dose for early breast cancer in Japanese women.
  
  
  METHODS
  A phase I study was designed using a scheme of dose-escalation from 19, 20, and 21 Gy at 90% isodose. The primary endpoint was early toxicity. Secondary endpoints were efficacy for a long period and late toxicity. Inclusion criteria were as follows: (1) tumor size <2.5 cm, (2) age >50 years, (3) surgical margin >1 cm, (4) intraoperative pathologically free margins, (5) written informed consent. Exclusion criteria were (1) contraindication to radiation therapy, (2) extensive intraductal component. Partial resection was performed with at least a 1-cm margin around the tumor. Radiation was delivered directly to the mammary gland employing a MOBETRON device. Toxicity was evaluated with the Common Terminology Criteria for Adverse Events (CTCAE), version 3.0.
  
  
  RESULTS
  From December 2007 to September 2008, 9 patients were enrolled in the study. The first three patients received a radiation dose of 19 Gy. Within 3 months toxicity in each case was deep connective tissue fibrosis (grade 1: 2/3, grade 2: 1/3). The next three patients received a dose of 20 Gy and had toxicities of deep connective tissue fibrosis (grade 1: 3/3), hematoma (grade 1: 2/3), infection in the musculoskeletal soft tissue (grade 1: 2/3), and soft tissue necrosis (grade 2: 1/3). The final three patients received a dose of 21 Gy and had toxicities of deep connective tissue fibrosis (grade 1: 2/3), hematoma (grade 1: 1/3), infection in the musculoskeletal soft tissue (grade 1: 1/3), and soft tissue necrosis (grade 2: 2/3).
  
  
  CONCLUSIONS
  The IORT treatment was tolerated very well in Japanese women, and we now recommend the dose of 21 Gy.
authors.affiliation: Department of Breast and Endocrine Surgery, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku 466-8550, Nagoya, Japan. m-sawaki@med.nagoya-u.ac.jp
authors.forename: Masataka
authors.initials: M
authors.lastname: Sawaki
authors.forename: Shigenori
authors.initials: S
authors.lastname: Sato
authors.forename: Toyone
authors.initials: T
authors.lastname: Kikumori
authors.forename: Shunichi
authors.initials: S
authors.lastname: Ishihara
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Aoyama
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Itoh
authors.forename: Akimasa
authors.initials: A
authors.lastname: Nakao
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Imai
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D007564:Japan; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D021701:Sentinel Lymph Node Biopsy