Robot-assisted vs. Open Nipple-sparing Mastectomy With Immediate Breast Reconstruction

the purpose of the study: It provides the highest level of evidence ever studied on the use of robotic surgical systems during breast surgery for breast cancer treatment, and aims to reveal the clinical significance of successive breast reconstruction(immediate breast reconstruction, IBR) at the same time as Robot-assisted nipple-sparing mastectomy (RNSM)

* Background: Robot-assisted nipple-sparing mastectomy (RNSM) has emerged for breast cancer treatment and for risk reducing mastectomy in women who have high risk of pathogenic variants. Even though several studies have reported that RNSM is a feasible procedure, some argue that RNSM is only performed by several specialized surgeons and there is only limited data reporting about the oncologic outcomes and patient reported outcomes (PRO). Recently, the United States Food and Drug Administration and several surgeons have warned that robot breast surgery should be performed only by specialized surgeons and the benefits, risks, and alternatives of all available treatment options should be discussed with patients to make the most informed treatment decision. The Korea Robot-Endoscopy Minimal Access Breast Surgery Study Group (KoREa-BSG) has been established to evaluate, standardize, and teach this cutting-edge procedure. We designed a prospective multicenter randomized clinical trial evaluating oncologic outcomes of RNSM with immediate breast reconstruction (IBR) compared to open conventional NSM (CNSM) with IBR, which is Robot vs. Open nipple-sparing Mastectomy trial (ROM trial).
* Detail description: This study is a multi-organ randomized clinical trial that evaluates oncological results of RNSM compared to Conventional Nipple Sparing Mastectomy (CNSM).

Retrospective studies on robot-endoscopic surgery have shown that beginners are technically feasible and reliable with a short learning curve.

However, the absence of a well-organized randomized trial remains a major limitation in expanding robotic surgery in breast surgery worldwide, so in this study, we designed a prospective multi-organ randomized trial 'Robot-to-Open Nipple Preservation Mastectomy Clinical Trial' compared to CNSM for oncological results after RNSM and IBR.

* Data collection: Collections of clinical pathological factors include height, weight, breast volume/weight, age, germline likely pathogenic/pathogenic mutation, affected breast, bilateral surgery, breast ptosis, Tumor size, TNM stage, histological grade, histological type, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor (HER), Ki67 levels, nipple invasion status, adjuvant/neoplastic treatment status, and postoperative complications by clavien-Dindo classification, surgical time, border invasion, postoperative drainage/period, RRM performance, reconstruction type, patient's pre-surgical recurrence status, medical cost data, and follow-up data.
* Subject satisfaction assessment: After 3 to 12 months (+-30 days) of final surgery, the subject was surveyed to evaluate satisfaction with robotic surgery. Follow the BREAST-Q Korean questionnaire for evaluation.
* Cost effectiveness evaluation according to surgical method (option): The cost effectiveness of robotic surgery is evaluated by surveying the subject 3 to 12 months after the final surgery (+-30 days). Follow the EQ5D Korean.

Eligibility Criteria:
Inclusion Criteria:

* Adult women over the age of 19 with breast cancer scheduled for therapeutic mastectomy and who want immediate reconstruction
* Stage 0-III breast cancer at initial evaluations
* ECOG performance status of 0 or 1

Exclusion Criteria:

* Patients planned for breast-conserving surgery or who are not candidates for IBR are excluded.
* Clinical evidence for nipple or skin involvement of tumors in preoperative evaluations
* A pregnant or lactating woman
* Only tumors with lobular carcinoma in situ
* Mammary Paget's disease
* Inflammatory breast cancer
* Male breast cancer
* Stage IIIB-IV disease at initial presentation
* Women with breast Cup E or higher
* Previous history of breast cancer (metachronous breast cancer)
* Previous history of non-mammary malignant disease excluding non-melanoma skin cancer or thyroid papillary/follicular cancer
* Special type cancer (phyllodes tumor, sarcoma, and lymphoma)
* Age \> 70
* ASA, grade 4 or higher
* Patients who do not have the ability to give informed consent
* Previous thoracic radiation history
* Patients who have not been tested for hepatitis before surgery (HBV, HCV) and HIV (compensation insurance policy)