Comparison of the Safety and Aesthetic Outcomes of a Novel Endoscopic-Assisted Breast-Conserving Surgery (SRRSHzb-EABCS) With Those of Conventional Breast-Conserving Surgery (ZACA001)

October 30, 2026 updated by: Linbo Wang, Sir Run Run Shaw Hospital

This multicenter, open-label, prospective, randomized controlled study compares a novel endoscopy-assisted breast-conserving surgery technique (SRRSHzb-EABCS) with conventional open breast-conserving surgery (CBCS) in women with breast cancer who wish to preserve their breast.

Breast-conserving surgery followed by radiotherapy is a standard treatment for early-stage breast cancer. Conventional open surgery leaves visible scars on the breast, while traditional endoscopy-assisted techniques are time-consuming, difficult to learn, and costly. The investigators developed a novel technique, SRRSHzb-EABCS, which uses a gasless expansion-traction endoscopic system with a custom-built skin flap dissector and V-shaped retractor, together with percutaneous U-shaped metal wires placed around the marked tumor margin, enabling precise tumor localization and margin control through a single axillary incision. The technique is designed to be easier to learn, shorter in operative time, less expensive, and more cosmetic.

Eligible participants are randomly assigned in a 1:1 ratio to undergo either SRRSHzb-EABCS or conventional open breast-conserving surgery. The main goal of the study is to compare the intraoperative and postoperative positive margin rates between the two techniques. The study also compares aesthetic outcomes measured by BREAST-Q scores at 1 and 18 months after surgery, complication rates, and 5-year local recurrence, disease-free survival, and overall survival.

A total of 422 participants (211 per arm) will be enrolled at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, and multiple participating centers in China. Participants are followed at 1 month and 18 months after surgery, with long-term follow-up for up to 5 years.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Study Design: This is a multicenter, open-label, prospective, randomized controlled trial led by Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, with multiple participating centers in China.

Randomization: Eligible female patients with breast cancer who meet the inclusion criteria and sign informed consent are randomly assigned in a 1:1 ratio to the experimental group (SRRSHzb-EABCS) or the control group (conventional open breast-conserving surgery) one day before surgery. The randomization sequence is generated centrally by computer (ResMan system) with stratification by center.

Experimental intervention (SRRSHzb-EABCS): The procedure uses a gasless "expansion-traction" endoscopic system with two custom-built instruments (a skin flap dissector and a V-shaped retractor) and a metal wire-based system for tumor localization and margin control (Lu Y, et al. Laparoscopic, Endoscopic and Robotic Surgery, 2026; doi: 10.1016/j.lers.2026.08.004). Under general anesthesia, the patient is positioned supine with the affected arm abducted at 60-75 degrees and the ipsilateral shoulder elevated. A single 3.0-4.5 cm curvilinear incision is made in the axilla, limited to the triangular area bounded by the lateral border of the pectoralis major and the anterior border of the latissimus dorsi. Preoperative ultrasound delineates the tumor margin; a circular outline 1.5-2.0 cm from the tumor edge is marked on the skin and divided into eight equal segments to define cutting points, with four marking points positioned circumferentially between alternating pairs of cutting points. Sentinel lymph node biopsy or axillary lymph node dissection is performed through the axillary incision, and the retromammary space is then dissected endoscopically toward the tumor, with the upper blade of the V-shaped retractor used in traction mode to maintain a stable working space. Four circumferential U-shaped cutting wires (0.3 mm metal wire advanced via a 20G angiocatheter, with limbs insulated by sheaths) are placed percutaneously along the resection boundary, and two insulating marking wires are placed in a cross configuration posterior to the tumor within the retromammary space as visual guides; additional wires are used for large or irregularly shaped tumors. The subcutaneous flap is dissected with the custom-built skin flap dissector, and the V-shaped retractor is then repositioned in expansion mode with both blades spread apart to maintain the superficial working space. The ends of each U-shaped wire are connected to an electrocautery pencil; under endoscopic vision, the wire is lifted vertically and activated, cutting precisely along the pre-determined resection plane ("hot-wire" cutting). The remaining parenchymal bridges are divided using standard laparoscopic instruments guided by the marking wires. The specimen is removed en bloc through the axillary incision, and all margins are assessed by intraoperative frozen section; positive margins undergo re-excision through the same incision, and repeatedly positive margins lead to mastectomy. The defect is reconstructed with a pedicled glandular flap using volume displacement oncoplastic technique, titanium clips are placed in the tumor bed, and the cavity is drained and closed.

Control intervention (conventional open breast-conserving surgery): Performed according to the Chinese Anti-Cancer Association guidelines for breast-conserving therapy, generally with separate breast and axillary incisions. The resection includes the tumor with surrounding breast tissue, with oncoplastic volume displacement or replacement techniques when needed. Specimen margins are marked and assessed (margin inking and/or intraoperative frozen section and imprint cytology), 4-6 titanium clips are placed in the tumor bed. If a margin is positive on intraoperative or postoperative pathology, local re-excision of the margin is performed, and if margins remain repeatedly positive, mastectomy is performed.

Axillary management in both groups: sentinel lymph node biopsy for clinically node-negative patients, with axillary lymph node dissection according to biopsy results; clinically node-positive patients undergo axillary lymph node dissection directly.

Pathology and adjuvant therapy: All specimens are examined by pathologists according to the Chinese Anti-Cancer Association breast cancer guidelines, and all margin results are recorded in the case report form. Postoperative adjuvant therapy is determined by the treating physician according to current guidelines and recorded.

Follow-up: Participants are followed at 1 month and 18 months after surgery to record complications and complete BREAST-Q assessments. Long-term follow-up for local recurrence, disease-free survival, and overall survival continues for 5 years after surgery.

Sample size: Based on pilot data from the lead center, the positive margin rate of SRRSHzb-EABCS was 25% compared with 15% for conventional open surgery. Using a non-inferiority margin of 10%, a one-sided alpha of 0.025, and 80% power, and accounting for a 5% dropout rate, 211 participants are required per arm (422 in total).

Safety monitoring: All intraoperative and postoperative complications (including wound infection, postoperative bleeding, seroma, and flap necrosis), their management, and outcomes are recorded in the case report form.

Study Type

Interventional

Enrollment (Estimated)

422

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Zhejiang
      • Hangzhou, Zhejiang, China
        • Recruiting
        • Sir Run Run Shaw Hospital, Zhejiang University School of Medicine
        • Contact:
        • Contact:
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • The First Affiliated Hospital, Zhejiang University School of Medicine
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • Zhejiang Provincial People's Hospital
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Traditional Chinese Medicine)
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • The Second Affiliated Hospital, Zhejiang University School of Medicine
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • Women's Hospital, Zhejiang University School of Medicine
      • Hangzhou, Zhejiang, China
        • Not yet recruiting
        • Zhejiang Cancer Hospital, Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences
      • Huzhou, Zhejiang, China
        • Not yet recruiting
        • Huzhou Central Hospital
      • Jinhua, Zhejiang, China
        • Not yet recruiting
        • Affiliated Jinhua Hospital, Zhejiang University School of Medicine
      • Lishui, Zhejiang, China
        • Not yet recruiting
        • Lishui Municipal Central Hospital
      • Ningbo, Zhejiang, China
        • Not yet recruiting
        • Ningbo Medical Center Lihuili Hospital
      • Ningbo, Zhejiang, China
        • Not yet recruiting
        • Ningbo First Hospital
      • Ningbo, Zhejiang, China
        • Not yet recruiting
        • Ningbo No.2 Hospital
      • Ningbo, Zhejiang, China
        • Not yet recruiting
        • Ningbo Women and Children's Hospital
      • Quzhou, Zhejiang, China
        • Not yet recruiting
        • Quzhou People's Hospital
      • Shaoxing, Zhejiang, China
        • Not yet recruiting
        • Shangyu People's Hospital
      • Shaoxing, Zhejiang, China
        • Not yet recruiting
        • Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine)
      • Taizhou, Zhejiang, China
        • Not yet recruiting
        • Taizhou Hospital of Zhejiang Province
      • Taizhou, Zhejiang, China
        • Not yet recruiting
        • Taizhou Central Hospital (Taizhou University Hospital)
      • Wenzhou, Zhejiang, China
        • Not yet recruiting
        • The First Affiliated Hospital of Wenzhou Medical University
      • Yiwu, Zhejiang, China
        • Not yet recruiting
        • Yiwu Maternity and Children Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Female

Description

Inclusion Criteria:

  1. Female;
  2. Aged 18-70 years;
  3. Preoperative pathologically confirmed diagnosis of breast cancer, treated at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine (lead center) or other participating centers;
  4. Voluntary participation in the study with signed informed consent;
  5. Desire for breast conservation;
  6. Clinical stage I-II early breast cancer: tumor size T1-T2, with adequate breast volume and an appropriate tumor-to-breast volume ratio, such that a satisfactory breast shape can be maintained after surgery;
  7. Selected patients with clinical stage III disease (except inflammatory breast cancer) who meet the criteria for breast-conserving surgery after downstaging by preoperative therapy may be carefully considered;
  8. Signed informed consent and willingness to receive standard postoperative adjuvant therapy and long-term follow-up.

Exclusion Criteria:

  1. Pregnant or lactating women;
  2. History of radiotherapy to the ipsilateral chest wall;
  3. Severe dysfunction of major organs, such as heart or lung;
  4. History of other malignant tumors;
  5. Extensive lesions for which negative margins or a satisfactory cosmetic outcome cannot be achieved;
  6. Diffusely distributed malignant-appearing calcifications;
  7. Multifocal or multicentric lesions;
  8. Positive dimple sign;
  9. Preoperative imaging indicating invasion of the skin or pectoralis major;
  10. Refusal to enter the randomization process;
  11. Vulnerable populations, including persons with mental illness, cognitive impairment, critically ill patients, minors, pregnant women, and illiterate persons.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: SRRSHzb-EABCS group

Participants undergo the novel endoscopy-assisted breast-conserving surgery SRRSHzb-EABCS, which uses a gasless expansion-traction endoscopic system with two custom-built instruments (a skin flap dissector and a V-shaped retractor) and percutaneously placed U-shaped metal wires for tumor localization and margin control. Through a single 3.0-4.5 cm axillary incision, the retromammary space and subcutaneous flap are created, and each U-shaped cutting wire is connected to an electrocautery pencil and energized to cut precisely along the planned resection margin under endoscopic vision ("hot-wire" cutting). Specimen margins are assessed by intraoperative frozen section; if a margin is positive, local re-excision of the margin is performed, and if margins remain repeatedly positive, mastectomy is performed. The defect is reconstructed with a pedicled glandular flap using volume displacement oncoplastic technique.

A novel gasless endoscopy-assisted breast-conserving surgery using an expansion-traction system (a skin flap dissector and a V-shaped retractor) and a metal wire-based tumor localization system. Through a single 3.0-4.5 cm axillary incision, the retromammary space is created endoscopically. The resection margin is marked 1.5-2.0 cm beyond the tumor edge; U-shaped cutting wires and marking wires are placed percutaneously. The flap is dissected while the V-shaped retractor maintains the working space. Each cutting wire is energized with an electrocautery pencil to cut along the planned margin ("hot-wire" cutting). Margins are assessed by frozen section; positive margins undergo local re-excision, and repeatedly positive margins lead to mastectomy. Axillary management: sentinel lymph node biopsy (SLNB) for clinically node-negative patients, with axillary lymph node dissection (ALND) performed according to biopsy results; clinically node-positive patients undergo ALND directly.

Active Comparator: Conventional breast-conserving surgery (CBCS) group

Participants undergo conventional open breast-conserving surgery performed according to the Chinese Anti-Cancer Association guidelines for breast-conserving therapy, generally through separate breast and axillary incisions. The resection includes the tumor with surrounding breast tissue; specimen margins are marked and assessed (margin inking and/or intraoperative frozen section and imprint cytology); 4-6 titanium clips are placed in the tumor bed; and oncoplastic volume displacement or replacement techniques are used when needed. If a margin is positive on intraoperative or postoperative pathology, local re-excision of the margin is performed, and if margins remain repeatedly positive, mastectomy is performed.

Conventional open breast-conserving surgery performed according to the Chinese Anti-Cancer Association guidelines for breast-conserving therapy. Generally, separate incisions are made on the breast and in the axilla. The resection includes the tumor together with a margin of surrounding breast tissue. Specimen margins are marked and assessed (inking and/or intraoperative frozen section). Four to six titanium clips are placed in the tumor bed for radiation boost localization. Oncoplastic volume displacement or volume replacement techniques are applied when needed. If a margin is positive on intraoperative or postoperative pathology, local re-excision of the margin is performed, and if margins remain repeatedly positive, mastectomy is performed. Axillary management: sentinel lymph node biopsy (SLNB) for clinically node-negative patients, with axillary lymph node dissection (ALND) performed according to biopsy results; clinically node-positive patients undergo ALND directly.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Intraoperative and Postoperative Positive Margin Rate
Time Frame: Intraoperatively and up to 1 month after surgery (final pathology report)

Proportion of participants with positive resection margins of the breast-conserving specimen, including the first and any subsequent positive margins on intraoperative frozen section assessment and the positive margin rate on postoperative routine paraffin pathology.

Intraoperatively and up to 1 month after surgery (final pathology report)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Intraoperative and Postoperative Complications
Time Frame: Intraoperatively and up to 1 month (±2 weeks) after surgery

Incidence of intraoperative and postoperative complications, including wound infection, postoperative bleeding, subcutaneous seroma, and flap necrosis, with their management and outcomes recorded. Complications are counted per participant (one participant with complications counts as one event).

Intraoperatively and up to 1 month (±2 weeks) after surgery
Aesthetic Outcome and Quality of Life Assessed by BREAST-Q
Time Frame: 1 month (±2 weeks) and 18 months (±3 months) after surgery

Patient-reported aesthetic outcome (breast appearance satisfaction) and quality of life, measured by the BREAST-Q questionnaire (breast-conserving therapy module).

1 month (±2 weeks) and 18 months (±3 months) after surgery
Local Recurrence Rate
Time Frame: From the date of surgery up to 5 years (5-year assessment window: ±6 months)

Proportion of participants with ipsilateral breast tumor recurrence (local recurrence) during follow-up.

From the date of surgery up to 5 years (5-year assessment window: ±6 months)
Disease-Free Survival (DFS)
Time Frame: From the date of surgery up to 5 years (5-year assessment window: ±6 months)

Time from surgery to the first occurrence of local recurrence, distant metastasis, or death from any cause, whichever occurs first.

From the date of surgery up to 5 years (5-year assessment window: ±6 months)
Overall Survival (OS)
Time Frame: From the date of surgery up to 5 years (5-year assessment window: ±6 months)

Time from surgery to death from any cause.

From the date of surgery up to 5 years (5-year assessment window: ±6 months)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Principal Investigator: Linbo Wang, Sir Run Run Shaw Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 1, 2023

Primary Completion (Estimated)

January 31, 2029

Study Completion (Estimated)

December 31, 2033

Study Registration Dates

First Submitted

October 30, 2026

First Submitted That Met QC Criteria

October 30, 2026

First Posted (Actual)

November 5, 2026

Study Record Updates

Last Update Posted (Actual)

November 5, 2026

Last Update Submitted That Met QC Criteria

October 30, 2026

Last Verified

October 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • SRRSH2023-0215
  • ChiCTR2300068807 (Registry Identifier: Chinese Clinical Trial Register (ChiCTR))

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual participant data will be made available upon reasonable request to qualified researchers, following approval by the principal investigator and the Ethics Committee of Sir Run Run Shaw Hospital, in compliance with applicable Chinese regulations on personal data protection.

IPD Sharing Time Frame

Beginning 6 months after publication of the primary results and available for 5 years.

IPD Sharing Access Criteria

Researchers with a methodologically sound proposal may submit a request to the principal investigator (linbowang@zju.edu.cn). Access will be granted after ethics approval and execution of a data use agreement.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • ICF

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.