Feasibility of intraoperative radiation therapy for early breast cancer in Japan: a single-center pilot study and literature review

Breast Cancer. 2014 Jul;21(4):415-22. doi: 10.1007/s12282-012-0412-8. Epub 2012 Sep 25.


Background: Intraoperative radiation therapy (IORT) is under evaluation in breast-conserving surgery because the feasibility of the IORT procedure including transportation of the patient under general anesthesia is not well established. Thus, this prospective single-center study aimed to test the feasibility of IORT at a single dose of 21 Gy in Japanese breast cancer patients.

Methods: The primary endpoint was early toxicity; the secondary endpoint was late toxicity. Patients with histologically or cytologically proven primary early breast cancer were eligible. Inclusion criteria were as follows: (1) T < 2.5 cm; (2) desire for breast-conserving surgery; (3) age >50 years; (4) surgical margin >1 cm; (5) intraoperative pathologically free margins; and (6) sentinel node negative. Exclusion criteria were (1) contraindications to radiation therapy; (2) past radiation therapy for the same breast or chest; (3) extensive intraductal component; and (4) a tumor located in the axillary tail of the breast. All patients gave written informed consent. Partial resection was performed with at least a margin of 1 cm around the tumor. The patient was transported from the surgical suite to the radiation room. Radiation (Clinac(®) 21EX, Varian Medical Systems, Inc.) at 21 Gy was delivered directly to the mammary gland. Toxicity was evaluated with the Common Terminology Criteria for Adverse Events V4.0.

Results: Five patients were enrolled in this pilot study and received 21 Gy. Follow-up ranged from 7.8 to 11.0 months (median 10.2). Intraoperative transportation to the radiation room during the surgical procedure under general anesthesia was performed safely in all patients. Treatment-related toxicities within 3 months were deep connective tissue fibrosis (grade 1, n = 3) and pain (grade 1, n = 3). There was no case of wound infection, wound dehiscence, or soft tissue necrosis. Overall, there was no severe adverse event.

Conclusions: The procedure was tolerated very well in this first group of Japanese female patients treated with IORT, as was the case with European women. A longer follow-up is needed for the evaluation of any potential late side effects or recurrences. A phase II study is now being conducted for the next group of patients (UMIN000003578).

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Aged
  • Breast Neoplasms / pathology
  • Breast Neoplasms / radiotherapy*
  • Combined Modality Therapy
  • Feasibility Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Intraoperative Care*
  • Mastectomy, Segmental
  • Middle Aged
  • Neoplasm Grading
  • Pilot Projects
  • Postoperative Complications*
  • Prognosis
  • Prospective Studies
  • Radiation Injuries*
  • Radiotherapy Dosage
  • Radiotherapy, Adjuvant