Jump to Main Contents

Home > Clinical depts > Department of Breast Surgery

Department of Breast Surgery

Kimiyasu Yoneyama, Takashi Hojo, Chisako Yamauchi


We treat patients with operable malignant mammary glands. Diagnosis of breast disease, surgical treatment and follow-up for breast cancer patients are mainly our professional practice. The Department consists of three staff surgeons and one resident, and is committed to providing the latest, most comprehensive breast treatments for our patients. The multidisciplinary approach to the diagnosis and treatment of cancer are carried out through cooperation between related specialists: surgeons, radiologists, plastic surgeons, pathologists, medical oncologists, specialized nurses, and technicians.

The Department mainly focuses on “minimally invasive surgery” and performs a thorough investigation for an oncologically safe approach, less morbidity and good cosmesis. For example, although sentinel lymph node (SLN) biopsy has already been established as the standard care for clinical node negative patients, omitting axillary lymph node dissection (ALND) for positive SLNs with micro- or macrometastasis has started in clinical practice as an expanded indication. On the other hand, preoperative systemic therapy provides the opportunity for a curative operation or breast-conserving surgery to avoid mastectomy. Moreover, we can provide breast reconstructive surgery in collaboration with the Plastic Surgery Division. These procedures will contribute to a better quality of life for patients with breast cancer.

Routine activities

For the regular activities of the Department, a daily morning routine round is scheduled for inpatients by all staff and residents. Moreover, our weekly preoperative diagnostic imaging conference on breast cancer is conducted on Monday evenings to discuss the surgical treatment planning for each patient. A clinical conference to decide on courses of treatment by multidisciplinary breast care team members is held twice a month. A monthly pathological conference on breast cancer is also conducted on the last Friday of each month. At those conferences, individual cases are presented to a team of highly trained cancer specialists, including radiologists, breast surgeons, pathologists, radiation oncologists, and medical oncologists. Indeed, our multidisciplinary team approach to breast cancer treatment sets the quality of care we provide for our patients well apart from the norm.

Changes in the annual number of patients with breast cancer who underwent surgery are shown in Table 1. A total of 313 patients with primary breast cancer and 46 patients with recurrence or other breast disease were operated on. 14 immediate breast reconstruction surgeries were included. Of the patients with primary breast cancer, 71 (23%) underwent primary systemic therapy. The types and number of operative procedures performed in 2015 are shown in Table 2. The rate of breast-conserving surgeries (including two radiofrequency ablation alone cases) was 60% (187/313). Sentinel node biopsy was performed in 255 patients, and 238 patients were spared from ALND.

Research activities

Evaluation of the potential role of Ki67 as a biomarker for breast cancer patients.

The Ki67 index is a marker for cell proliferation. A retrospective search of a prospectively maintained clinical breast cancer database was performed. It was concluded that the pre-therapy Ki67 index was a useful predictor for the therapeutic response to neoadjuvant chemotherapy and Ki67 post-therapy was shown to predict outcomes for patients with residual invasive disease.

Long-term results of patients treated with sentinel node biopsy (SNB) omitting ALND.

In an observational study, there was not a significant difference in the overall survival and relapse-free survival between SLN negative patients without ALND and those with ALND. We concluded that SLN biopsy without ALND is validated as a safe and effective method for regional node treatment of SLN negative breast cancer patients. We are planning to omit ALND even in SLN positive patients.

In vivo cancer detection with a newly designed fluorescent probe.

γ -glutamyl hydroxymethyl rhodamine green (gGlu-HMRG) is a small-molecule aminopeptidase probe which was enzymatically cleaved, revealing a bright fluorescent region of cancer cells which overexpress the enzyme γ -glutamyltranspeptidase (GGT). Visualized tiny cancerous nodules may allow us to delineate the border of tumors and confirm that there are no residual tumors.

Clinical trials

Radiofrequency ablation (RFA) using a Cool-tip electrode system (RAFAELO study).

A phase II study on RFA without resection was performed for T=<1.5 cm, N0 breast cancer patients with no extensive intraductal components using a Cool-tip electrode system. This study is certified as an advanced medical treatment by the Ministry of Health, Labour and Welfare.

Effectiveness of primary tumor resection for metastatic breast cancer (The Japan Clinical Oncology Group (JCOG) 1017).

In this multicenter clinical trial, the primary tumor resection plus systemic therapy arm is compared to the systemic therapy alone arm in metastatic breast cancer.

Intensive vs. standard post-operative surveillance in high-risk breast cancer patients (JCOG1204, INSPIRE Trial).

This is a multi-center randomized phase III trial which started in 2012. This clinical trial is to confirm the superiority of an intensive follow-up to standard follow-up in terms of overall survival in high-risk breast cancer patients.

Postoperative therapy with endocrine and TS-1 (POTENT study).

This multi-center randomized trial started in 2012 and is a randomized, controlled study to determine whether S-1 combined with standard postoperative endocrine therapy more effectively inhibits recurrence than standard postoperative endocrine therapy alone in patients with estrogen receptor (ER)-positive, HER2-negative primary breast cancer.

Observational study of axilla treatment for breast cancer patients with SLN positive.

This multi-center study is designed to evaluate the outcome of no ALND in sentinel node-positive breast cancer using the propensity score. Patients with 1 to 3 positive micrometastasis or macrometastasis in sentinel lymph nodes are eligible. The primary endpoint is the recurrence rate of regional lymph nodes in patients treated with SNB. Patients treated with SNB followed by ALND are also registered simultaneously to compare the prognosis.


Our education targets are to raise knowledge about breast disease and to operative technical improvement.

Future prospects

We want to solve the appropriate postoperative follow-up that was a longtime problem in breast cancer medical care by clinical trial. And aim at operative development with more minimally invasive surgery.

  • Table 1. Number of primary breast cancer patients operated on during 2006-2015
  • Table 2. Type of operative procedures performed in 2015 for primary breast cancer

List of papers published in 2015


  1. Hojo T, Masuda N, Mizutani T, Shibata T, Kinoshita T, Tamura K, Hara F, Fujisawa T, Inoue K, Saji S, Nakamura K, Fukuda H, Iwata H. Intensive vs. Standard Post-Operative Surveillance in High-Risk Breast Cancer Patients (INSPIRE): Japan Clinical Oncology Group Study JCOG1204. Jpn J Clin Oncol, 45:983-986, 2015
  2. Komoike Y, Inokuchi M, Itoh T, Kitamura K, Kutomi G, Sakai T, Jinno H, Wada N, Ohsumi S, Mukai H, Japanese Breast Cancer Society. Japan Breast Cancer Society clinical practice guideline for surgical treatment of breast cancer. Breast Cancer, 22:37-48, 2015