Surgical and Oncologic Outcomes After Robotic Nipple Sparing Mastectomy and Immediate Reconstruction
Surgical and Oncologic Outcomes After Robotic Nipple Sparing Mastectomy and Immediate Reconstruction
Robotic mastectomy with immediate reconstruction was introduced by Toesca et al. in 2015.
 Since then, several studies have reported the safety and feasibility of robotic
 nipple-sparing mastectomy with immediate reconstruction. However, most studies were conducted
 by single centers and had small samples. Furthermore, there is a lack of studies comparing
 surgical and oncologic outcomes between robotic nipple-sparing mastectomy and conventional
 nipple-sparing mastectomy. For this reason, this study evaluates surgical and oncologic
 outcomes of robotic nipple-sparing mastectomy with immediate reconstruction using
 international multi-center data.
This study is an international multi-center pooled analysis using prospective and
 retrospective studies to evaluate surgical and oncologic outcomes of robotic nipple-sparing
 mastectomy with immediate reconstruction.

 Raw data for robotic or conventional nipple-sparing mastectomy from Severance Hospital,
 Samsung Medical Center, the European Institute of Oncology, Changhua Christian Hospital, and
 Gustave Roussy is collected. Among them, Severance Hospital takes the lead at performing
 analysis from the data. Storage and disposal of patients' records are managed by each
 researcher. In the analysis process, although the collaborators can request records from
 Severance Hospital if necessary, they are only supposed to be provided computerized data
 which were originally clinical data from patients who already ended treatments. In this case,
 individual identifying data and medical records are not shown.

 Clinicopathologic variables including operation times, hospital stay, medical history,
 smoking history, family history, BMI, menopausal status, specimen weight, TNM stage, grade,
 histological type, estrogen receptor, progesterone receptor, HER2, Ki 67, and perivascular
 involvement are analyzed.

 Postoperative complications within 30 days are collected and classified by the Clavien-Dindo
 grade. Locoregional recurrence-free survival and local and systemic recurrences are examined.
 Patients whose data have been retrospective for at least one month are to be examined.

 Patient's and surgeon's satisfaction using Breast Q is evaluated. Categorical variables are
 examined using the chi-square test or Fisher's exact test if indicated.

 Continuous variables are examined using the independent t-test or ANOVA if indicated.

 The estimated sample size from the four institutions is about 300 cases for robotic
 nipple-sparing mastectomy and matched cases for conventional nipple-sparing mastectomy.

 Propensity matching analysis is applied to reduce confounding factors.
Inclusion Criteria:

 -  Women who underwent nipple sparing mastectomy and immediate reconstruction

 -  Women with early breast cancer

 -  Women with germline BRCA 1/2 mutation or germline mutations in genetic susceptibility
 genes

 -  Women with interstitial mastopathy

 -  Women with risk-reducing mastectomy or contralateral mastectomy

 Exclusion Criteria:

 -  Male patients

 -  Women with stage IV disease at diagnosis

 -  Women who underwent previous breast cancer surgery

 -  Women who received prior radiotherapy for the ipsilateral breast