A Japanese prospective multi-institutional feasibility study on accelerated partial breast irradiation using multicatheter interstitial brachytherapy: clinical results with a median follow-up of 60 months.

Abstract

BACKGROUND:

We carried out the first multi-institutional prospective study on accelerated partial breast irradiation (APBI) via multicatheter interstitial brachytherapy in a shorter period for early breast cancer in Japan.

METHODS:

Patient eligibility criteria included positive hormone receptors, tumors ≤ 3 cm and TNM stage pN0M0. After breast-conserving surgery (Japanese cylindrical resection) and histological confirmation of negative surgical margins and the absence of lymph node metastasis, applicator implantation was performed either postoperatively or intraoperatively. High-dose-rate brachytherapy of 36 Gy in 6 fractions was delivered.

RESULTS:

Forty-six patients from six institutions received this treatment regimen, and the median follow-up time was 60 months (range 57-67 months). The median resected breast tissue volume was 81 cm3 (range 28-260 cm3). No Grade 4 late sequela, local recurrence nor death due to breast cancer were observed. Grade 2-3 sequelae such as rib fracture (2%), soft tissue necrosis (9%), fibrosis (20%), and breast pain (9%) were observed. The resected breast tissue volumes of the patients who had Grade ≥ 2 fibrosis and Grade < 2 fibrosis were 105.9 ± 32.3 cm3 and 76.3 ± 45.6 cm3, respectively, p = 0.02. The overall cosmetic outcome score of Excellent/Good was 74% at 60 months after APBI. Grade ≥ 1 fibrosis was observed in 44% and 92% of patients who scored Excellent/Good and Fair/Poor, respectively, p = 0.004.

CONCLUSIONS:

This study showed excellent local control and survival results with minimal late sequelae.

• Authors: Ken Yoshida, Takayuki Nose, Yuki Otani, Shuuji Asahi, Iwao Tsukiyama, Takushi Dokiya, Toshiaki Saeki, Ichirou Fukuda, Hiroshi Sekine, Yu Kumazaki, Takao Takahashi, Tadayuki Kotsuma, Norikazu Masuda, Eisaku Yoden, Kazutaka Nakashima, Taisei Matsumura, Shino Nakagawa, Seiji Tachiiri, Yoshio Moriguchi, Jun Itami, Masahiko Oguchi
• Journal: Breast cancer (Tokyo, Japan) (Breast Cancer) Vol. 29 Issue 4 Pg. 636-644 (Jul 2022) ISSN: 1880-4233 [Electronic] Japan
• PMID: 35303282 (Publication Type: Journal Article, Multicenter Study)
• Copyright: © 2022. The Author(s), under exclusive licence to The Japanese Breast Cancer Society.

Topics

• Brachytherapy (methods)
• Breast Neoplasms (pathology, radiotherapy, surgery)
• Combined Modality Therapy
• Feasibility Studies
• Female
• Fibrosis
• Follow-Up Studies
• Humans
• Japan
• Mastectomy, Segmental (methods)
• Prospective Studies
• Radiotherapy Dosage
• Treatment Outcome