Oncological outcome of single-port insufflation endoscopic nipple-sparing mastectomy versus open mastectomy in early breast cancer patients: a study protocol for a randomised controlled trial.

Introduction: Breast cancer is the most prevalent cancer and the leading cause of cancer-related death in women. Conventional open mastectomy (C-OM) is one of the most common procedures for breast cancer, which involves the removal of the nipple-areola complex and a large proportion of the breast skin, leading to poor cosmetic effect and restriction of upper extremity function. Single-port insufflation endoscopic nipple-sparing mastectomy (SIE-NSM) could conceal the incision along the wrinkles in the axilla, preserve all the breast skin and nipple-areola complex and provide a better cosmetic outcome and quality of life. This trial aims to investigate the oncological safety between SIE-NSM and C-OM in early breast cancer patients.

Methods And Analysis: This is a single centre, non-blinded, randomised controlled trial (RCT) and will be conducted at Beijing Friendship Hospital. Patients will be enrolled in the inpatient ward. Breast surgeons will notify patients who meet the inclusion and exclusion criteria with the instruction of this RCT. Patients will be randomly assigned to C-OM or SIE-NSM with a 3:1 allocation as per a computer-generated randomisation schedule. Patients will be followed-up for 12 months for analysing surgical outcomes. The primary outcome is the local recurrence rate at a 12-month follow-up. The secondary outcome is the distant metastasis rate, cosmetic satisfaction score and psychosocial well-being score after a 12-month follow-up. To ensure the accuracy of the cosmetic satisfaction score and psychosocial well-being score, the standard scale, Breast-Q score, will be applied.

Ethics And Dissemination: This study will be conducted according to the medical ethics committee of the Beijing Friendship Hospital and according to the principles of the Declaration of Helsinki. All patients will receive clear instruction of their disease and treatment plan. Informed consent will be obtained from all patients when they agree to comply with our research plan. The results will be disseminated at academic presentations and publications in peer-reviewed journals. The raw data will be confidentially stored in our electronic data capture database. Data will not be shared unless an appropriate data request is submitted after the trial completion and peer-review journal publication.

Trial Registration Number: NCT04461847.