Annual Report 2024
Department of Breast Surgery
Tatsuya Onishi, Chisako Yamauchi, Rurina Watanuki, Miki Yamada, Asako Yamamoto, Yurika Ide
Introduction
In 2024, the Department of Breast Surgery at the National Cancer Center Hospital East experienced record surgical volumes, further solidifying its role as a leader in breast cancer treatment and innovation. Our team continued to advance minimally invasive approaches, strengthened collaboration with the Department of Plastic and Reconstructive Surgery, and actively contributed to national and international clinical research initiatives.
Routine Activities
During the year, 599 primary breast cancer surgeries and 69 surgeries for recurrent or other breast disease were performed. Among primary cases, breast-conserving surgery was chosen in 293 patients (49%), while mastectomy, including nipple-sparing procedures, was conducted in 297 patients. Endoscopic nipple-sparing mastectomy including prophylactic mastectomy was applied in 37 cases. Immediate breast reconstruction was performed in 23 patients, including 12 DIEP flaps, 2 latissimus dorsi flaps, and 9 tissue expander placements. Axillary management was tailored to disease status: sentinel lymph node biopsy (SNB) alone in 475 patients, SNB followed by axillary dissection in 37 patients, and upfront axillary dissection in 60 patients.
Table 1. Newly Diagnosed Primary Breast Cancer Patients by Stage (2020-2024)
Research Activities
Our department contributed to several ongoing multicenter trials including JCOG1505, JCOG1806, and JCOG1017. We participated in observational and interventional studies covering a wide spectrum, such as radiofrequency ablation (RFA) for early breast cancer, hereditary breast and ovarian cancer, management of insomnia (WJOG14921B), and development of specialized underwear for survivors. We also initiated a collaborative retrospective study with U.S. partners examining local recurrence after breast-conserving therapy.
The Team and What We Do
Our team is dedicated to providing comprehensive care from diagnosis to surgical treatment and postoperative follow-up. The multidisciplinary approach integrates surgery, systemic therapy, radiology, pathology, and reconstruction. Despite staff shortages due to maternity leave, the team maintained consistent clinical quality by sharing responsibilities.
Table 2. Types of Primary Breast Cancer Surgery (2024)
Table 3. Immediate Breast Reconstruction (2024)
Clinical Trials
We actively participated in clinical trials such as JCOG1505 (endocrine therapy for ER-positive DCIS), JCOG1806 (omission of surgery in HER2-positive patients with complete response), and JCOG1017 (primary tumor resection in metastatic breast cancer). Additional trials included RFA for early breast cancer, which received insurance coverage in late 2023.
Education
Two residents received structured surgical and academic training throughout the year. Hands-on operative teaching and regular conferences ensured steady improvement of their clinical and research skills.
Future Prospects
We anticipate further adoption of minimally invasive breast surgery, with endoscopic and robot-assisted nipple-sparing mastectomy expected to be considered for insurance reimbursement by 2026. Our department aims to lead in standardizing surgical techniques, establishing evidence-based safety, and promoting dissemination across Japan.
List of papers published in 2024
Journal
1. Akechi T, Furukawa TA, Noma H, Iwata H, Toyama T, Higaki K, Matsuoka H, Zenda S, Iwatani T, Akahane K, Inoue A, Sagara Y, Uchida M, Imai F, Momino K, Imaizumi G, Yamaguchi T, Mashiko T, Miyaji T, Horikoshi M, Sakurai N, Onishi T, Kanemitsu Y, Murata T, Wanifuchi-Endo Y, Kuroda H, Nishikawa R, Miyashita M, Abe M, Uchitomi Y. Optimizing smartphone psychotherapy for depressive symptoms in patients with cancer: Multiphase optimization strategy using a decentralized multicenter randomized clinical trial (J-SUPPORT 2001 Study). Psychiatry and clinical neurosciences, 78:353-361, 2024
2. Miyazaki N, Iwasaki T, Sakai H, Watanuki R, Tanizawa Y, Cai Z, Kawaguchi T, Tsurutani J, Nagashima K. Risk factors for recurrence in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative early breast cancer in Japan: a systematic literature review and meta-analysis. Current medical research and opinion, 40:827-837, 2024
3. Tan RYC, Ong WS, Lee KH, Park S, Iqbal J, Park YH, Lee JE, Yu JH, Lin CH, Lu YS, Ono M, Ueno T, Naito Y, Onishi T, Lim GH, Tan SM, Lee HB, Koh J, Han W, Im SA, Tan VKM, Phyu N, Wong FY, Tan PH, Yap YS. Outcomes in Nonmetastatic Hormone Receptor-Positive HER2-Negative Pure Mucinous Breast Cancer: A Multicenter Cohort Study. Journal of the National Comprehensive Cancer Network : JNCCN, 22:e237121, 2024