# Robotic nipple-sparing mastectomy with immediate prosthetic reconstruction: A prospective study about 138 consecutive procedures

M. Lherm, D. Chaltiel, A. Roulot, N. Leymarie, J.-F. Honart, F. Rimareix, S. Delaloge, S. Michiels, B. Sarfati

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## To cite this version:

M. Lherm, D. Chaltiel, A. Roulot, N. Leymarie, J.-F. Honart, et al.. Robotic nipple-sparing mastectomy with immediate prosthetic reconstruction: A prospective study about 138 consecutive procedures. Annales de Chirurgie Plastique Esthétique, 2025, 10.1016/j.anplas.2025.09.002. inserm-05419003

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https://inserm.hal.science/inserm-05419003v1

Submitted on 16 Dec 2025

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ELSEVIER

Available online at

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Elsevier Masson France

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ANNALES

CHIRURGIE
PLASTIQUE
ESTHETIQUE

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Département de chirurgie plastique
Institut de chirurgie plastique
Université de Lyon
Lycée de laMode
2 rue des États-Unis
69678 Clichy-sur-Oise

ORIGINAL ARTICLE

# Robotic nipple-sparing mastectomy with immediate prosthetic reconstruction: A prospective study about 138 consecutive procedures

Mastectomie robot-assistée avec conservation de la plaque aérolo-mamelonaire immédiate prothétique : une étude prospective à propos de 138 procédures consécutives

M. Lherm<sup>a,*</sup>, D. Chaltiel<sup>c,d</sup>, A. Roulot<sup>b</sup>, N. Leymarie<sup>b</sup>, J.-F. Honart<sup>b</sup>, F. Rimareix<sup>b</sup>, S. Delaloge<sup>b</sup>, S. Michiels<sup>c,d</sup>, B. Sarfati<sup>b</sup>

Received 20 April 2025; received in revised form 7 September 2025; accepted 9 September 2025

KEYWORDS

Robotic surgery;
Breast cancer;
Nipple sparing
mastectomy

Summary

**Background and purpose.** — Robotic nipple-sparing mastectomy (RNSM) is becoming popular for the treatment of breast cancers because of the absence of scars on the breasts. The aim of this study is to assess the feasibility and the safety of RNSM with immediate prosthetic breast reconstruction (IPBR).

**Methods.** — In this single-arm, monocentric and prospective study, RNSM with IPBR was offered, in case of prophylactic or therapeutic surgery of breast cancers, to patients with breast cup $\le C$ and moderate ptosis. The primary goal was the rate of full thickness skin or areola necrosis. As a second objective we meant to assess the rate of conversion to open technique and postoperative complications. We also analysed pre- and postoperative BREAST-Q scores and aesthetic out-

E-mail address: mathilde.lherm@chu-lyon.fr (M. Lherm).

https://doi.org/10.1016/j.anplas.2025.09.002

0294-1260/© 2025 The Authors. Published by Elsevier Masson SAS. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

<footnote><sup>a</sup>Service de chirurgie des brûlés, plastique, reconstructrice et esthétique, hospices civils de Lyon, Lyon, France</footnote>

<footnote><sup>b</sup>Service de chirurgie plastique et reconstructrice, Gustave-Roussy, Villejuif, France</footnote>

<footnote><sup>c</sup>Service de biostatistique et d'épidémiologie, Gustave-Roussy, Villejuif, France</footnote>

<footnote><sup>d</sup>CESP, Inserm U1018, université Paris Sud, université Paris-Saclay, Villejuif, France</footnote>

<footnote>* Corresponding author.</footnote>
MOTS CLÉS

Chirurgie robotique ;
Chirurgie robot-assistée ;
Reconstruction
mammaire ;
Mastectomie
prophylactique ;
Conservation aréole

comes by submitting them to independent surgeons and to the patients themselves.

**Results.** — In total, 138 RNSM with IPBR were performed in 79 patients between December 2015 and January 2020. There were two cases of full thickness skin or areolar necrosis (1.5%), nine infections (6.5%), and nine implants loss (6.5%). We had to switch to an open technique in two cases (1.5%) and in four cases we had to surgically drain four hematoma (2.9%). The patient's physical and sexual well-being evaluated by BREAST-Q was not impacted by the surgery. The aesthetical outcomes are satisfying for both the patients and the main surgeon as well as for a panel of independent plastic surgeons.

**Conclusions.** — This study does attest to the feasibility, the reproducibility, and the safety of this approach.

© 2025 The Authors. Published by Elsevier Masson SAS. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Résumé

**Introduction.** — Les indications de mastectomie avec conservation de l'aréole sont en constante augmentation. La technique de mastectomie robot-assistée permet d'effectuer le geste avec une rançon cicatricielle minimale, située sous le bras. L'objectif de cette étude est d'attester de la faisabilité et de la sécurité de cette technique.

**Matériel et méthodes.** — Nous présentons une étude prospective monocentrique de faisabilité et de sécurité, réalisée entre décembre 2015 et janvier 2020. Le geste chirurgical a été réalisée à l'aide du robot Da Vinci XI. L'objectif est de démontrer une non-infériorité par rapport aux techniques conventionnelles, avec une cicatrice réduite et en dehors du sein. Le critère principal d'évaluation est le taux de nécrose cutanée. Les critères secondaires relevés sont la durée de la procédure et les complications post opératoires. Nous avons aussi recueilli les réponse des patientes à un questionnaires de qualité de vie (BREASTQ).

**Résultats.** — Cette chirurgie a été réalisée sur 138 seins et les patientes ont toutes bénéficié d'une reconstruction mammaire immédiate prothétique. Nous avons relevé 1 nécrose totale d'aréole (0,7 %) et 1 nécrose totale de mamelon (0,7 %), 9 infections de prothèse (6,5 %), 2 coques (1,4 %) et nous rapportons 2 conversions en voie ouverte (1,5 %) et 4 drainages d'hématome au bloc opératoire (2,9 %).

**Conclusions.** — La technique de mastectomie avec conservation de l'aréole robot-assistée permet donc de proposer une chirurgie fiable, reproducible avec un taux de nécrose cutanée très bas et une cicatrice discrète, très appréciée des patientes.

© 2025 Les Auteurs. Published by Elsevier Masson SAS. Cet article est publié en Open Access sous licence CC BY (http://creativecommons.org/licenses/by/4.0/).

Introduction

Breast cancer is a very frequent pathology and we are now able to achieve good long-term prognosis for a lot of patients. Furthermore, we now can identify patients at high and very high risks of breast cancer to whom we can offer preventive or risk reducing mastectomies. One of the challenges when it comes to breast cancer patients' care is the ability to enhance aesthetic results and quality of life for those patients without altering the long-term morbidity and mortality.

The developments and democratization of robotic surgery in other specialities allow minimally invasive surgeries with really good quality of working conditions and results (3D vision, endowrist technology, motion scaling, tremor control) so that plastic surgeons could avoid most challenges encountered with endoscopic nipple sparing mastectomy and reconstruction.

Some authors have already published studies on first cohorts and results of robotic nipple sparing mastectomy (RNSM) associated with immediate breast reconstruction (autologous or prosthetic) [1–5] and this technique seems to offer low nipple areolar complex (NAC) necrosis rate and a rapid learning curve. With RNSM we can offer the patient an

adequate prophylactic or curative treatment for breast cancer with minimally invasive surgery and hidden scars. Many patients with high risk of breast cancer apprehend prophylactic surgery and RNSM is an approach that permits prophylactic mastectomy with no scar in the mammary area.

In a specific group of patients, nipple sparing mastectomy (NSM) has already proved to be a feasible and safe option in terms of long-term survival outcomes [6,7] and aesthetics results after a prophylactic mastectomy. The main complication observed in these cases is NAC necrosis. We now have official recommendations about when we can offer NSM to breast cancer patients [8,9] and NSM promotes immediate breast reconstruction and improves aesthetic outcomes with a smaller number of procedures.

After publishing our first case [10], surgical technique [1] and preliminary results [11], we now present in this article the final results of our cohort study of RNSM with immediate prosthetic breast reconstruction (IPBR).

Methods

The patients were enrolled in a prospective, single arm, monocentric, safety study from December 2015 to January
2020 in accordance with the Good Clinical Practice guidelines and the Declaration of Helsinki (n° ID-RCB 2015-A00745-44). The institutional review board at Gustave-Roussy, an ethics committee, and health authorities approved the study protocol.

Every patient provided signed information consent for RNSM with immediate prosthetic breast reconstruction (IPBR) according to established regulations. These were the criteria we used for the patient selection: age between 18 and 70 years, with breast cup size $\le C$, ptosis $\le B$ (Regnault scale) and present Eastern Cooperative Oncology Group score of $\le 1$. Patients were excluded if postoperative radiotherapy was indicated, in case of previous breast surgery or irradiation or in the case of the presence of high-risk factor for skin or NAC necrosis (such as more than 20 cigarettes a day and/or uncontrolled diabetes).

In the case of prophylactic surgery, RNSM was indicated if a high-risk for breast cancer has been identified (with or without genetic mutation). In the case of oncologic therapeutic surgery, RNSM was indicated if the tumour was located more than 2 cm away from the NAC, according to our institutional recommendations.

Follow-up visits were scheduled 1, 3, 6 and 12 months after the procedure. Patients completed a Breast-Q questionnaire before and 12 months after the procedure. During the follow-up visit of the 6th and 12th month, the patient and the surgeon completed a satisfaction questionnaire elaborated by the authors.

## Endpoints

The primary endpoint is to assess the rate of skin and/or areolar necrosis.

The secondary endpoints are: to identify the rate of conversion to open technique, postoperative complications (hematoma with surgical drainage, infection and implant loss) and drainage duration. Furthermore, we included an aesthetic evaluation by the patient and by the surgeon 6 and 12 months after the NSM. The pre- and postoperative BREAST Q scores were analysed.

We also did an analysis of aesthetic outcomes by four independent plastic surgeons using 6 months postoperative photography (front, right, and left at 45-degree angles). We chose to evaluate the outcomes as described by Emiroglu et al. [12]: the shape and size of the breast, state of the skin and scar, symmetry, and NAC location were all scored on a scale of 1–4. These points were computed to form the panel aesthetic score (20–16 – excellent; 15–11 – good; 10–6 – moderate; 5–1 – poor).

## Surgical technique

We describe here the last version of the surgical procedure because between 2015 and 2020 the procedure went through some evolutions; for example we modified the scar from vertically to horizontally and we added acellular dermal matrix or mesh (TIGR® Matrix, SURGIMEND® Integra) between the implant and the skin to better define the implant pocket.

All procedures were performed with the Da Vinci® Xi™ Dual Console System, Model IS4000 (Intuitive Surgical®,

Sunnyvale, CA). The patient is laid on a flat supine position with the arm above the head with an internal rotation and a 90° abduction. The robot is place near the patient's head. The hospital's protocol for antibiotic prophylaxis is cefazoline 2 g intravenous before incision and 1 g per 4 additional hours of surgery.

There are two scars hidden by the patient's arm: The first one is 4 cm long and horizontally located within the footprint of the bra and the second and smallest one (8 mm) is located 7 cm under the first one, both being behind the anterior axillary line (Fig. 1).

The first part of procedure is to dissect the skin flap by scissors after a tumescent infiltration (500 cm³ to 1 L) with a saline solution containing 1 mg/L of adrenalin. The infiltration permits the reduction of bleeding and facilitates skin flap dissection.

The robot docking is guided by the target sign, which has to be centred on the middle port and aligned with the nipple. One multi-instrument port (GelPOINT mini® advanced access platform, Applied Medical) is used for the largest incision for two ports and a third port is used in the smaller incision.

One more port can be positioned in the GelPOINT mini® for blood and smoke aspiration or to be used by the assistant to grasp the gland but also to help the surgeon with a classic endoscopic grasper.

Before introducing some instruments, we inject carbon dioxide with a constant 8 mmHg pressure to open our working space. The 30° camera (Intuitive Surgical®, Denzlingen, Germany) is introduced first in the middle port to allow non-traumatic insertion of the other instruments. Under vision, exposure and traction is performed by using the bipolar grasping forceps (Intuitive Surgical®, Sunnyvale, CA) in the left port. Dissection is performed with the monopolar-curved scissors (Intuitive Surgical®, Sunnyvale, CA) in the right port.

Because of a lack of tactile feedback when using the robot, the surgeon cannot control if an instrument is applying any pressure on the skin, so the assistant is near the table and closely monitors that no excessive pressure is applied on the patient's skin during the entire dissection.

The subcutaneous dissection of the gland is robotically completed and then the gland is separated from the pectoralis major muscle in a lateral to medial way (Fig. 2).

The robot is undocked, the GelPOINT mini® is removed and the gland is manually extracted "en bloc" through the largest incision. The implant is placed through the largest incision in a pre-pectoral position and the pocket is closed laterally with two or three stitches between the acellular dermal matrix or mesh and the thoracic wall to avoid implant malposition. The drain is placed through the small incision and we close the skin.

In our study, the patients had expander, anatomical implant or round implant, with or without acellular dermal matrix or mesh as we have described here the surgical technique in the most current version.

After the procedure, the patient has a compressive dressing for two days and wears a sports bra, day and night, for a month. The drains are removed and the patient is discharged when less than 50 cm³ per day.
<figure><img src="image_6.png" /><figcaption>**Figure 1** Preoperative markings.</figcaption></figure>

## Statistical analysis

Based on the assumption that skin and/or areola necrosis rate will be 5%, we estimated that 140 mastectomies would provide a confidence interval of 8%. Then we estimated that 75 women would provide around 140 mastectomies.

Categorical variables are summarized in frequency tables, with the counts and percentage of patients in each category.

Regarding BREAST-Q, scores were calculated with QScore version 1.0 and we present pre- and postoperative results (mean and range) for physical well-being of the chest and the abdomen and sexual well-being, then choose to present box plot for comparison of pre- and postoperative results.

The comparison between our results and literature has been done by Fisher's test. Significant results were defined with a P-value < 0.05.

## Results

A total of 79 patients were included and underwent 139 RNSM procedures with IPBR between December 2015 and January 2020. Ten patients benefited from therapeutic RNSM and all

other patients underwent prophylactic surgery (n = 69), of which 13 patients, had unilateral and 56 patients had bilateral prophylactic surgeries.

Patients' demographic characteristics are shown in Table 1.

### Primary endpoint

We observed skin and/or areolar necrosis on two breasts on two different patients (Table 2). The rate of necrosis is so 2.6% (95% CI: 0.3%–9%) per total number of patients and 1.4% (95% CI: 0.2%–5.1%) per number of procedures. In those two cases, implants were lost.

### Other endpoints with rate calculated by number of procedures

We observed two cases (rate: 1.4%) of conversion to an open technique with an inframammary fold incision: the first case was to perform the haemostasis of an uncontrolled bleeding caused by an internal mammary perforator and the second because of a very fatty breast with difficulties for gland
<figure><img src="image_7.png" /><figcaption>**Figure 2** The view of the operating field, as seen by the surgeon. Above retroareolar area and below prepectoral dissection.</figcaption></figure>

grasping with robotic instruments (Table 2). We observed four (2.9% rate) hematomas with surgical drainage.

There were seven implant infections (5% rate), first managed with antibiotics and revision surgery to clean the pocket and change the implant, this way we could save two implants and we lost five implants for infection.

The mean length of stay is 6.5 days (range: 3–12) and is comparable to the duration of drainage because patients were discharged only after the drains had been removed.

Concerning total anaesthesia durations, we observed a mean of 326 minutes, we show the evolution over time of total anaesthesia durations in the Fig. 3. Those data were extracted for 46 patients.

## BREAST-Q

We observed respectively means of 82.4 [min: 46; max: 100] for preoperative physical well-being of the chest and 88.4 [min: 46; max: 100] for preoperative physical well-being of the abdomen (Fig. 4). Concerning preoperative sexual well-being, we observed a mean of 65.9 [min: 29; max: 100].

About postoperative results, we observed respectively means of 76.5 [min: 43; max: 100] for physical well-being of the chest, 87.5 [min: 46; max: 100] for physical well-being of the abdomen and 67.5 [min: 16; max: 100] for sexual well-being.

<table><caption>**Table 1** Patients (n = 79) and mastectomy (n = 139) characteristics.</caption><tbody><tr><td>Age, year, mean (range)</td><td>38.5 [23.7–56.2]</td></tr><tr><td>BMI, kg/m<sup>2</sup>, mean (range)</td><td>21.1 [17.4–34.2]</td></tr><tr><td>Chest size, number of patients (%)</td><td></td></tr><tr><td>75</td><td>2 (3%)</td></tr><tr><td>80</td><td>3 (4%)</td></tr><tr><td>85</td><td>20 (26%)</td></tr><tr><td>90</td><td>40 (51%)</td></tr><tr><td>95</td><td>11 (14%)</td></tr><tr><td>100</td><td>2 (3%)</td></tr><tr><td>ND</td><td>1</td></tr><tr><td>Cup size, number of patients (%)</td><td></td></tr><tr><td>A</td><td>11 (14%)</td></tr><tr><td>B</td><td>49 (62%)</td></tr><tr><td>C</td><td>19 (24%)</td></tr><tr><td>Regnault classification of ptosis, number of patients (%)</td><td></td></tr><tr><td>0</td><td>39 (55%)</td></tr><tr><td>1</td><td>18 (25%)</td></tr><tr><td>2</td><td>12 (17%)</td></tr><tr><td>3</td><td>1 (1%)</td></tr><tr><td>4</td><td>1 (1%)</td></tr><tr><td>ND</td><td>8 (11%)</td></tr><tr><td>Smoking status, number of patients (%)</td><td></td></tr><tr><td>Smokers (not declared)</td><td>2 (3%)</td></tr><tr><td>Ex smokers</td><td>6 (8%)</td></tr><tr><td>Non-smokers</td><td>71 (91%)</td></tr><tr><td>Indication, number of RNSM (%)</td><td></td></tr><tr><td>Prophylactic mastectomy</td><td>69 (87%)</td></tr><tr><td>Therapeutic mastectomy</td><td>10 (13%)</td></tr><tr><td>Bilateral surgery, number of patients (%)</td><td>61 (77%)</td></tr><tr><td>Genetic mutation BRCA 1 or 2, number of patients (%)</td><td>69 (90%)</td></tr></tbody></table>

We had others postoperative results without preoperative and without comparison. Satisfaction with postoperative breast had a mean of 66.2 [min: 36; max: 100], satisfaction with outcomes had mean of 78.6 [min: 35; max: 100],

<table><caption>**Table 2** Endpoints: results.</caption><tbody><tr><td>Number of patients</td><td>79</td></tr><tr><td>Number of procedures</td><td>139</td></tr><tr><td>Length of drainage, number of days (range)</td><td>6.5 (3–12)</td></tr><tr><td>Complications: number (rate over all procedures)</td><td></td></tr><tr><td>Full thickness skin/areola necrosis</td><td>2 (1.4%)</td></tr><tr><td>Hematoma with surgical drainage</td><td>4 (2.9%)</td></tr><tr><td>Implant infection</td><td>7 (5%)</td></tr><tr><td>Implant loss: because of</td><td></td></tr><tr><td>Infection</td><td>9 (6.5%)</td></tr><tr><td>Necrosis</td><td>5 (3.6%)</td></tr><tr><td>Capsular contracture</td><td>2 (1.4%)</td></tr><tr><td>Seroma</td><td>7 (5%)</td></tr><tr><td>Conversion to open technique</td><td>2 (1.4%)</td></tr><tr><td>Operating time, minutes, mean (standard deviation)</td><td>326 (126.2)</td></tr></tbody></table>
<figure><img src="image_8.png" /><figcaption>**Figure 3** Total anaesthesia duration and learning curve (n = 46).</figcaption></figure>

psychosocial well-being had a mean of 73.7 [min: 42; max: 100] and the satisfaction with nipples had a mean of 87.5 [min: 50; max: 100].

We could compare pre- and postoperative results about sexual and physical (chest and abdomen) well-being for respectively 60, 65 and 32 patients. We can see that the physical well-being of the chest is not significantly different between pre- and postoperative BREAST-Q scores, the sexual well-being is the same pre- and postoperatively.

## Aesthetical outcomes

Patients and surgeon expressed that they were mostly satisfied or very satisfied not only by the volume, shape, texture, symmetry of the breast but also by the position and the aspect of the NAC. Percent of patients responding to questions regarding the sensitivity of the breast and the NAC, was similar between the 'satisfied' and 'not very satisfied' response categories (Fig. 5).

<figure><img src="image_9.png" /><figcaption>**Figure 4** BREAST – Q box plot.</figcaption></figure>
<figure><img src="image_10.png" /><figcaption>Figure 5 Aesthetical outcomes patient vs. surgeon.</figcaption></figure>

The evaluation of aesthetic outcomes by independent surgeons (the first 60 consecutive patients) reveal a total mean of 16/20 with independent means at 16.1/20, 15.6/20, 17.4/20 and 15.8/20. Those results are between good and excellent according to Emiroglu et al. scale [12].

Discussion

The comparison of our data on the rate of necrosis with rates reported in the literature showed that we achieved significantly a lower rate of necrosis (2.6% per total number of patients) compared to rates reported in cohorts of patients undergoing open/conventional NSM the non-robotic cohorts in comparison while the rates reported in cohorts of patients undergoing RNSM were not significantly different than the rate reported in our study (Table 3) [6,13–15].

Our hypothesis is that robotic mastectomy performed with the distant scar allows maintenance of breast skin vascularisation with no scar located in the breast area, thus preserving the dermal and subdermal vascular plexus. Furthermore, the use for a retractor is more traumatic to the skin flap than CO₂ insufflation (constant 8 mmHg) so it prevents skin suffering during the surgery. Patients with prior breast surgery and radiotherapy were excluded in our study, which further allowed for a better prognosis for NAC necrosis.

The technique changed and improved over the years, from the first patient reconstructed by expander in a retro-pectoral position with 7.18 hours for a bilateral surgery (non-robotic surgery, robot docking and robotic surgery) to the last patient reconstructed by a pre-pectoral definitive implant with an acellular dermal matrix or mesh with 6.08 hours for a bilateral surgery. There was not a significant

<table><caption>Table 3 Comparison with literature.</caption><thead><tr><th></th><th>Total</th><th>Necrosis (areola and/or skin)</th><th>Rate</th><th>Fisher test (P)</th></tr></thead><tbody><tr><td><strong>NSM</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Headon et al. (2016)</td><td>10,143</td><td>602</td><td>5.94</td><td><strong>0.017</strong></td></tr><tr><td>Endara et al. (2013)</td><td>1776</td><td>76</td><td>4.28</td><td>0.119</td></tr><tr><td>Devita et al. (2016)</td><td>1647</td><td>135</td><td>8.20</td><td><strong>0.002</strong></td></tr><tr><td>Salibian et al. (2019)</td><td>1045</td><td>70</td><td>6.70</td><td><strong>0.012</strong></td></tr><tr><td><strong>RNSM</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Lee et al. (2021)</td><td>41</td><td>1</td><td>2.44</td><td>0.547</td></tr><tr><td>Toesca et al. (2021)</td><td>40</td><td>0</td><td>0.00</td><td>1</td></tr></tbody></table>

NSM: nipple-sparing mastectomy; RNSM: robotic nipple-sparing mastectomy. Bold means that significative result with p < 0.05.
difference in the learning curve in our cohort from first to the last patient, in contrast to other studies due to constant evolution of the reconstruction technique and ongoing training of other surgeons on the robotic nipple sparring mastectomy procedure.

As the study progressed, the type of implants used were modified, we choose to use only round and smooth implants: a precaution taken because of the potential risk of breast implant-associated anaplastic large-cell lymphoma, in accordance with our hospital recommendations. We now use the acellular dermal matrix or mesh to better define the implant pocket and avoid implant malposition.

Our study showed excellent outcomes for aesthetic results (Fig. 6) and quality of life with IPBR procedure that may be because of including majority of bilateral and symmetric procedures. We additionally offered fat grafting 6 months after the RNSM-IPBR needed, when the implant is visible or in the presence of implant rippling for example. Another important factor contributing to our excellent aesthetic outcomes is the location of the scar outside the breast area, it preserve us from NAC malposition and physiological retractions. The only open surgery that prevents those complication is the inframammary fold scar which is however responsible for a wide interruption of dermal and subdermal vascular plexus.

It is important to understand that breast reconstruction is a very versatile surgery and the selection of patients for RNSM depends on several factors including patient's morphology (breast size and possible reconstructive technique), willingness and general characteristics (autologous or prosthetic patient choice, radiotherapy, smoking status...).

In this cohort, we only did IPBR although latissimus dorsi pedicled flap is already described for autologous reconstruction in RNSM [4], the scar design allow to proceed to harvest

the flap by a short scar procedure [16] and even muscle sparring latissimus dorsi harvest [17]. In the future we can hope to also do free flap reconstruction along with RNSM with (or without) robotic microsurgery, some authors are evaluating feasibility of those procedures with anastomosis with latissimus dorsi pedicle.

Regarding the sensitivity of NAC and breast, owe did not see any significant patient satisfaction possibly due to the fact that mastectomy does not preserve the fourth intercostal perforator nerve which is responsible, for the NAC sensitivity. In the future, better results for NAC sensitivity could be achieved by nerve grafting for areola neurotization after the mastectomy.

It seems be hard to evaluate the real cost of a RNSM for the hospital: on one hand it's important to consider the initial cost of purchase of the robot, its annual maintenance and the cost of disposable equipment, all contributing to an initial upfront increase in RNSM costs. However, on the other hand, the lower rate of complications, the improvement of aesthetic outcomes and quality of life with a lower number of procedures decrease perioperative costs. Concerning the surgical durations, even if they are initially longer than classic open surgeries, we suppose that the learning curve will allow for continues decrease in operative time as surgeons gain experience and compensate the higher costs like in others surgeries [18]. The diffusion and democratisation of RNSM depends on more studies focused on robotic surgeries' costs in this surgery, as it had been done for prostatectomy [19].

The da Vinci Xi/X Surgical System is approved for use in patients undergoing prophylactic RNSM with reconstruction in the EU, Korea and Taiwan; and for use in breast cancer patients in Korea. We're still waiting for the Food and Drug Administration to authorize the use of robotic surgery for mastectomy and other cancer-related surgeries in international common practice [19].

<figure><img src="image_11.png" /><figcaption>**Figure 6** Pre- and postoperative (3 months) photography, without fat grafting.</figcaption></figure>
Conclusion

This study of 139 consecutive RNSM procedures attests to the feasibility, the reproducibility and the safety of this approach. The main benefits of RNSM are: a minimally invasive approach with hidden scars and respect of the skin flap vascularization, that allows us to achieve a low rate of NAC necrosis, which is the most frequent complication of NSM. Furthermore, the IPBR permits good aesthetic outcomes and patient quality of life is preserved after the surgery and a high satisfaction for patients.

These results are to be confirmed by further prospective, comparative studies between the traditional NSM technique and RNSM with a larger series of patients.

Disclosure of interest

The authors declare that they have no competing interest.

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