# Endoscopic prophylactic nipple-sparing mastectomy: First French survey of 10 patients

Gauthier Rathat, Maude Chaumette, Victoria Fontaine, Lucie Rebel, Joana

Pissarra, Claire Duflos, Martha Duraes

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Gauthier Rathat, Maude Chaumette, Victoria Fontaine, Lucie Rebel, Joana Pissarra, et al.. Endoscopic prophylactic nipple-sparing mastectomy: First French survey of 10 patients. Journal of Gynecology Obstetrics and Human Reproduction, 2025, 54 (1), pp.102862. 10.1016/j.jogoh.2024.102862. hal-05013778

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Original Article

# Endoscopic prophylactic nipple-sparing mastectomy: First French survey of 10 patients

Gauthier Rathat<sup>a, *</sup>, Maude Chaumette<sup>a</sup>, Victoria Fontaine<sup>a</sup>, Lucie Rebel<sup>a</sup>, Joana Pissarra<sup>b</sup>, Claire Duflos<sup>b, c</sup>, Martha Duraes<sup>a</sup>

<figure><img src="image_3.png" /></figure>

ARTICLE INFO

Keywords:

Endoscopic mastectomy

Prophylactic mastectomy

Breast reconstruction

Breast cancer

Breca

A B S T R A C T

**Introduction:** Current recommendations preconize prophylactic mastectomy for women over 30 with increased risk of breast cancer. Several surgical techniques are available to perform bilateral mastectomy with or without breast reconstruction. Our primary objective was to evaluate the feasibility of the Endoscopic Nipple Sparing Mastectomy (E-NSM) technique, without robotic assistance, using a single axillary incision and with immediate reconstruction using a prepectoral prosthesis in prophylactic indications. The secondary objectives were to evaluate the risks of postoperative complications and the esthetic results.

**Material and methods:** This is a preliminary report of a prospective single-center interventional clinical study with a final enrolment target of 20 patients. The primary endpoint was the rate of complete surgical procedures per E-NSM. The secondary endpoints were the rate of conversions to conventional surgery, infections, hematomas, skin injury, pain and esthetic results (Breast-Q questionnaire, additional cosmetic procedures).

**Results:** From April 2019 to June 2022, 10 patients were included for 19 procedures (9 bilateral mastectomies, 1 unilateral). All surgical procedures were complete; no conversion to conventional surgery was required. The rate of complications per procedure requiring revision surgery was 16 % (1 skin necrosis, 1 postoperative hematoma and 1 surgical site infection). No prosthesis was removed. The seroma rate was 5 %. All patients would recommend this technique and were very satisfied or satisfied with the esthetic result. A second cosmetic procedure (lipofilling) was necessary in 50 % of patients.

**Discussion:** These preliminary data attest to the feasibility and safety of the E-NSM approach, and should be confirmed on a larger cohort and longer-term follow-up.

ClinicalTrials.gov identifier: NCT03838549

Introduction

Approximately 5 to 10 % of breast cancers have a genetic origin [1]. The French National Cancer Institute (INCA) recommends bilateral mastectomy with or without breast reconstruction (immediate or delayed) from the age of 30 as part of a strategy to reduce breast cancer risk for patients carrying genetic mutations (BRCA 1/2, PALB2, p53) [2]. This procedure may also be proposed in the absence of a genetic predisposition and after validation by a multidisciplinary consultation meetings (MCM) namely, in the presence of family history of cancer, or history of contralateral cancer [3,4].

Nipple-sparing mastectomy (NSM) has become the reference technique in this indication [5], and its oncological safety is widely recognized [6-10]. However, the psychological impact of preventive mastectomy remains significant and is mainly due to esthetic factors (changes in body image, reduced sexual attractiveness, or problems with scar acceptance) [11]. Scar placement during prophylactic mastectomy is a key issue. Positioning must meet technical (complete removal of the gland), safety (vascularization of the Nipple-Areolar Complex – NAC, and risk of infection) and esthetic requirements [7,8]. In Conventional NSM (C—NSM), this positioning is always either on the breast or in its immediate periphery, and the scar is visible anteriorly (external radial,

<footnote><sup>a</sup> Department of gynaecological and breast surgery, CHU Arnaud de Villeneuve, 371 Av. du Doyen Gaston Giraud, 34090 Montpellier, France</footnote>

<footnote><sup>b</sup> Clinical Research and Epidemiology Unit, Montpellier University Hospital, Univ Montpellier, Montpellier, France</footnote>

<footnote><sup>c</sup> IDESP, INSERM, Univ Montpellier, CHU Montpellier, Montpellier, France</footnote>

<footnote>* Corresponding author at: CHU Arnaud de Villeneuve, 371 avenue du Doyen Gaston Giraud, 34090 Montpellier.</footnote>

<footnote>E-mail addresses: g-rathat@chu-montpellier.fr (G. Rathat), maude_chaumette@orange.fr (M. Chaumette), l-rebel@chu-montpellier.fr (L. Rebel), joana.dasilvapissarra@chu-montpellier.fr (J. Pissarra), c-duflos@chu-montpellier.fr (C. Duflos), m-duraes@chu-montpellier.fr (M. Duraes).</footnote>
sub mammary or areolar fold). Since 2015, robotic surgery has made it
possible to shift this scar to the axillary line (robotic NSM: R-NSM) [12].
In France, Sarfati et al. have published the results of 63 R-NSM pro-
cedures, using three robotic trocars and a prepectoral prosthetic implant
[13,14]. However, R-NSM still presents a problem of cost and access due
to regional disparities of centers equipped with robotics and difficult
access to such centers for this indication. The use of endoscopy in breast
surgery without robotic assistance is not new [15]. The triad defining
Endoscopic NSM (E-NSM) is more recent: a single incision hidden on the
axillary line, using endoscopic devices, with insufflation [16].

The aim of the MRIMOP study (“Mastectomie Reconstruction Im-
mediate par MOnotrocart et Pneumoscopie”, ClinicalTrials.gov identi-
fier: NCT03838549) is to assess the feasibility of prophylactic E-
NSMtechnique via an axillary incision. The secondary objectives are to
describe short- and medium-term outcomes, esthetic results, and patient
satisfaction. The total number of subjects to be included is 20, and we
present here the preliminary results on 10 patients;

Material and methods

Population

The first 10 patients were included between April 2019 and June 2022. Inclusion criteria were women aged 20 and over, with an indication for uni or bilateral prophylactic mastectomy, desiring immediate breast reconstruction, WHO performance index <3, breast volumes as follows: A, B or C bra cup size and glandular ptosis not exceeding 2 according to the Regnault classification [17].

The non-inclusion criteria were a history of oncological breast sur-
gery on the side concerned by the prophylactic mastectomy, history of
radiation treatment, breast hypertrophy requiring a nipple flap, smoking
over 10 cigarettes per day, BMI > 30 kg/m², large breast volume
requiring prostheses > 500 mL, chronic shoulder pain on the side to
operate, or on both shoulders, history of shoulder joint pathology on the
side to operate (retractile capsulitis, cuff tendinopathy) with persistent
deficit in active shoulder elevation.

Study design

This was a prospective, single-center interventional clinical study
carried out in the Obstetrics and Gynecology department and sponsored
by Montpellier University Hospital.

The primary endpoint was the rate of complete surgical procedures using this technique (removal of the gland through an incision in the axillary line, fitting of a definitive smooth prosthesis and no conversion to a conventional approach).

The secondary endpoints were to evaluate the intraoperative, im-
mediate postoperative and delayed postoperative effects.

During surgery, we recorded the operative time, the optimal insuf-
flation pressure, the existence of subcutaneous crepitus, the distance
between scar and outer edge of the gland, the size of the prosthesis, and
any complications with the skin sheath.

In the immediate postoperative period, the length of hospital stay, postoperative pain, postoperative hematomas requiring reoperation, NAC ischemia, infectious outcomes and the occurrence of seroma were evaluated.

Finally, for remote post-operative data, reconstruction quality was
assessed by self-questionnaires (breast Q) at months 3 and 12, combined
with a quality-of-life questionnaire (EQ5D). During this one-year follow-
up, serious complications requiring reintervention (implant change,
infection, NAC necrosis) and minor complications requiring no reinter-
vention (seroma, partial NAC ischemia) were noted during follow-up
consultations carried out at 1, 3, 6 months and 1 year after surgery.

Surgical technique

The surgical procedures were performed according to a previously
described technique [16], demonstrated in a published video (https://
ars.els-cdn.com/content/image/1-s2.0-S2468718924002290-mmc1.
mp4) [18]. All the procedures were performed by the same trained
practitioner. Preoperative drawings were made the preceding day. The
patient was placed in the supine position, with the contralateral arm in
abduction and the homolateral arm above the head, elbow flexed at 90°,
under general anesthesia. The first step consisted of a 4 cm skin incision
on the axillary line, centered on the NAC meridian. Then, subcutaneous
dissection using scissors was performed to reach the external quadrants,
after abundant infiltration of the cutaneous and glandular space with
adrenaline serum. Once the monotrocart was placed, subcutaneous CO2
insufflation was started. Subcutaneous dissection and prepectoral
detachment were continued using monopolar scissors. The breast spec-
imen was extracted through the skin incision at the same time as the
monotrocart.

Immediate breast reconstruction was performed by placing a
smooth, round silicone implant in the prepectoral pocket. The skin was
closed in two planes with Vicryl 2.0 stitches, followed by a Monosyn 4.0
intradermal suture (Fig. 1).

Statistical analysis

Qualitative variables were described by their number and percent-
age, quantitative variables by their mean, standard deviation, extrema,
median and quartiles. Analyses were performed using SAS Enterprise
Guide software (version 8.2, SAS Institute, Cary, NC, USA).

Ethics

The research was conducted in accordance with the French legisla-
tion, in particular the provisions relating to research involving the
human person in the Public Health Code, articles L1121-1 et seq., the
Bioethics laws, law N°78-17 of 6 January 1978 relating to information
technology, files and liberties, the Helsinki declaration, and Good
Clinical Practice. This study was validated by the French Ethics Com-
mittee (approval number 2018-A02591-54). All patients received clear
information and signed an informed consent form.

Results

Flow charts

From April 2019 to June 2022, 29 patients had an indication of prophylactic mastectomy. One patient had a low BMI (< 20 kg/m²) and required retropectoral implantation of prostheses to conceal their contours. Eighteen patients were excluded, mainly due to ptosis greater than grade 2 according to the Regnault classification, and large breast volume (Fig. 2). A total of 10 patients were included and underwent prophylactic E-NSM in the gynecological surgery department of Montpellier University Hospital. Nine patients underwent bilateral E-NSM, and one patient underwent unilateral E-NSM (history of breast cancer and irradiation on the other side), for a total of 19 prophylactic mastectomies (Table 1).

Primary endpoint

- Surgery feasibility

All surgical procedures were complete, meaning removal of the
gland through an incision on the axillary line and successful immediate
prosthesis placement was achieved, and no conversion to conventional
surgery was required. Details of the surgical procedures are given in
Table 2.
<figure><img src="image_4.png" /><figcaption>**Fig. 1.** Stages of endoscopic mastectomy using the Endoscopic Mastectomy technique. a) Preoperative drawing to identify the skin incision on the axillary line. b) Skin incision. c) Infiltration of the skin-glandular space using adrenaline serum. d) Placement of the monotrocart. e) Endoscopic view of the subcutaneous glandular dissection. f) Removal of the mammary gland through the skin incision. g) Insertion of a pre-pectoral smooth round breast prosthesis. h) Final appearance after closure and insertion of a drain.</figcaption></figure>

Secondary endpoint:

- Intraoperative data

The average operating time, defined by the time between skin opening and closure, was 125.1 ± 30.6 min per breast. The average distance between the scar and the outer edge of the gland was 3 ± 0.7 cm. With practice, the optimal insufflation pressure was stabilized at 8mmHG by the 3rd patient, and was not modified thereafter. A

complication related to subcutaneous insufflation occurred in one patient but did not lead to discontinuation of the procedure (discreet subcuatneal emphysema regressed spontaneously) One patient suffered a 2 cm² s-degree burn on one of the two breasts during the procedure. The main prosthesis volume was 307 ml.

- Immediate postoperative data

Hospital stays lasted on average 5 (± 1.2) days. Pain was at 1.5 (±
<figure><img src="image_5.png" /><figcaption>Fig. 2. Study flowchart.</figcaption></figure>

<table><caption>**Table 1**

Patients' baseline characteristics (N = 10).</caption><thead><tr><th></th><th>N = 10</th></tr></thead><tbody><tr><td>Age (years), mean (range)</td><td>39.2 (30–52)</td></tr><tr><td>BMI (kg/m²), mean (range)</td><td>21.7 (19.1–24.1)</td></tr><tr><td>Menopausal status, n (%)</td><td></td></tr><tr><td>Premenopausal</td><td>7 (88)</td></tr><tr><td>Postmenopausal</td><td>3 (30)</td></tr><tr><td>Breast volume – cup size, n (%)</td><td></td></tr><tr><td>B</td><td>7 (70)</td></tr><tr><td>C</td><td>3 (30)</td></tr><tr><td>Breast volume – chest size, n (%)</td><td></td></tr><tr><td>85 cm</td><td>9 (90)</td></tr><tr><td>95 cm</td><td>1 (10)</td></tr><tr><td>Regnault classification of ptosis, n (%)</td><td></td></tr><tr><td>0</td><td>8 (80)</td></tr><tr><td>1</td><td>2 (20)</td></tr><tr><td>Smoking status, n (%)</td><td></td></tr><tr><td>Non smoker</td><td>4 (40)</td></tr><tr><td>Ex-smoker</td><td>5 (50)</td></tr><tr><td>Smoking</td><td>1 (10)</td></tr><tr><td>Genetic mutation, n (%)</td><td></td></tr><tr><td>BRCA 1</td><td>4 (40)</td></tr><tr><td>BRCA 2</td><td>3 (30)</td></tr><tr><td>CDH1</td><td>1 (10)</td></tr><tr><td>Other<sup>a</sup></td><td>2 (20)</td></tr></tbody></table>

<table><caption>**Table 2**

Characteristics and intraoperative complications (N = 19).</caption><thead><tr><th>Characteristics</th><th>N = 19</th></tr></thead><tbody><tr><td>Insufflation pressure (mmHg), mean (range)</td><td>7.2 (6–8)</td></tr><tr><td>Specimen weight (g), mean (range)</td><td>228.9 (106–465)</td></tr><tr><td>Gel implant size (mL), mean (range)</td><td>339.0 (215–560)</td></tr><tr><td>Blood loss (mL), mean (range)</td><td>63.1 (49–120)</td></tr><tr><td>Effective operation times (min), mean (range)</td><td>125.1 (70–164)</td></tr><tr><td>Intraoperative complications, n (%)</td><td></td></tr><tr><td>Refractive hypercapnia</td><td>0 (0)</td></tr><tr><td>Skin burns</td><td>1 (5)</td></tr><tr><td>Haematoma</td><td>1 (5)</td></tr></tbody></table>

2.3)/10 on average, assessed with a Visual Analogue Scale (VAS) on day one. One patient had skin damage secondary to the intraoperative burn on one of the two breasts at 3-days post-op. One patient had bilateral partial superficial ischemia of the NAC and a hematoma of the right

breast at 1-day post-op, requiring repeat surgery to evacuate the hematoma without removal of the prosthesis.

## Late postoperative data

### Delayed Complications:

The patient who had an intraoperative burn consulted for skin necrosis at day 15 and exposure of the prosthesis at day 19 (5%). With the exception of this thermal injury, there was no spontaneous exposure for mechanical reasons. A second patient had an infection at day 14. None of these repeat operations required definitive removal of the prosthesis, and complete healing was achieved at 3 months post-operatively. One seroma was detected in one patient at 3 months, which healed by the 6-month visit. Healing of bilateral partial superficial NAC ischemia was achieved at 3 months after surgery. No total NAC necrosis was observed (Table 3).

### Esthetic, functional and quality of life (QOL) results

Detailed BreastQ score results at 3 and 12 months are shown in the Table 4.

Regarding patient satisfaction with their breasts (Question 1 from breast Q), the average satisfaction rate was 52 out of 64 maximum points at 3 months and was 54 out of 64 maximum points at 12 months. For the sexual well-being score, the median was 22 at 3 and 12 months, for a score between 6 and 30. Psychosocial well-being scores were 41 and 44 respectively, with a range from 10 to 50. All patients said they would do the same operation.

According to the surgeon's assessment, the aesthetic result is judged to be 90% symmetrical at 1 month, and 53% less so at 1 year. This was likely related to the formation of capsular contracture (41% type III according to Baker's classification at 12 months after surgery). No severe capsular contracture (Baker type IV) was observed. One-month

<table><caption>**Table 3**

Delayed postoperative complications (N = 19).</caption><thead><tr><th></th><th>1 month after surgery</th><th>3 month after surgery</th></tr></thead><tbody><tr><td>Major complications, n (%)</td><td>2 (11)</td><td>0 (0)</td></tr><tr><td>Infection</td><td>1 (5)</td><td>0 (0)</td></tr><tr><td>Prothesis exposure</td><td>1 (5)</td><td>0 (0)</td></tr><tr><td>Minor complications, n (%)</td><td>3 (16)</td><td>1 (5)</td></tr><tr><td>Delayed hematoma</td><td>0 (0)</td><td>0 (0)</td></tr><tr><td>Seroma</td><td>1 (5)</td><td>1 (5)</td></tr><tr><td>Partial NAC ischemia</td><td>2 (11)</td><td>0 (0)</td></tr></tbody></table>

<footnote>* Two patients did not have a genetic mutation but had significant family history of cancer.</footnote>

<footnote n="1">¹ time between incision and closing.</footnote>
<table><caption>**Table 4**
Results from Breast Q at 3 and 12 months.</caption><thead><tr><th>BREAST-Q c</th><th></th><th>Median M3</th><th>Median M12</th><th>Range</th></tr></thead><tbody><tr><td rowspan="3">Quality of life domains</td><td>psychosocial well being (Q4)</td><td>41</td><td>44</td><td>10–50</td></tr><tr><td>sexual well being (Q5)</td><td>22</td><td>22</td><td>6–30</td></tr><tr><td>physical well being (Q6)</td><td>41</td><td>34</td><td>16–80</td></tr><tr><td rowspan="7">Satisfaction domains</td><td>satisfaction with breast (Q1)</td><td>52</td><td>54</td><td>16–64</td></tr><tr><td>satisfaction with prothesis (Q2)</td><td>6</td><td>5</td><td>2–8</td></tr><tr><td>satisfaction with prothesis (Q3)</td><td>20</td><td>20</td><td>7–21</td></tr><tr><td>Satisfaction with care information (Q11)</td><td>54</td><td>56</td><td>15–60</td></tr><tr><td>Satisfaction with care surgeon (Q12)</td><td>48</td><td>48</td><td>12–48</td></tr><tr><td>Satisfaction with care medical stuff (Q13)</td><td>28</td><td>28</td><td>7–28</td></tr><tr><td>Satisfaction with care nursing (Q14)</td><td>28</td><td>28</td><td>7–28</td></tr></tbody></table>

post-operative results of two patients are shown in Fig. 3.

A second esthetic operation (one single session of lipofilling) was necessary in 50 % of patients. One patient underwent a change of prostheses to reduce the volume.

Shoulder function was assessed at 3 months after surgery using the Constant score and was evaluated at 88.0 ± 15 % of normal function expected for age. The most affected feature was muscle strength during lateral elevation of the shoulder.

The results of the EQ5D questionnaire (QOL) showed a median rate of 83 (50–100) at 3 months post-operatively, and 90 (20–100) at 12 months. The same rate had been evaluated pre-operatively at 90.

## Discussion

E-NSM appears to be a well-accepted surgical technique. No patient refused to take part in this pioneering study. This reinforces our

hypothesis that scar concealment is an important issue for these patients, even though there are no studies evaluating the impact on patients of scar concealment at the time of mastectomy. However, it should not be proposed to all patients with an indication of prophylactic mastectomy. As we observed in this study, 62 % of the patients selected had non-inclusion criteria, the main ones were ptosis greater than grade 2 according to the Regnault classification and too large breast volume. For these patients, the need for remodeling the skin flap was not compatible with the E-NSM.

This technique is an alternative to C—NSM and R-NSM, with the advantage of being accessible to any structure and less expensive than R-NSM [13,19]. According to Lai et al., the total cost of R-NSM is between $10,000 and $12,000 [19]. A medico-economic study comparing R-NSM and E-NSM will be necessary to support the economic interest of the endoscopic approach.

The E-NSM technique allows the prosthesis to be positioned in the prepectoral space. Locating the incision at distance from the prosthetic cavity probably limits the risk of exposure. Therefore, the use of endoscopic instruments could limit the risk of infection. Prepectoral implantation has several additional advantages: it reduces the risk of hematoma, limits shoulder pain and stiffness by limiting dissection, improves esthetic results with a non-visible scar, and reduces the risk of animation deformity [20]. The prepectoral localization also allows for one-stage reconstruction, without a tissue expansion phase. The use of an acellular matrix seems feasible and could reduce the rate of seromas [21,22].

In our study, the scar was located 3 cm from the prosthetic site and outside the breast contour on average. However, this incision size is incompatible with a large glandular volume or excessive implantation. E-NSM is well-suited for small or medium volume breasts, without the need for skin flap redraping, where an incision in the inframammary fold would be visible. In this study, the average volume of the implant was 339 mL, comparable to those found in the literature for E-NSM (304.3 ± 70.1 cc [23]) and R-NSM (312.5 cc [13]).

The mean operating time was just over 2 h (125.1 ± 30.6 min), which appears to be shorter than the operating times for E-NSM in other studies (previously described at 181.8 ± 32 min [24], 282.1 ± 113.4 min [25], or 197 min [26]). In patients requiring bilateral prophylactic mastectomy, it was necessary to reposition the patient completely to perform the mastectomy on the contralateral breast. The results in terms

<figure><img src="image_6.png" /><figcaption>**Fig. 3.** Results after bilateral mastectomy using the Endoscopic Mastectomy technique. Preoperative (left), 1 month after surgery (center), appearance of the axillary scar at 1 month after surgery (right).</figcaption></figure>
of operating time for R-NSM vary widely in the literature, ranging from 257.0 ± 59.7 min [27], to 279.8 ± 79.3 min for Lai et al. [19], and from 85 to 214 min per breast for Sarfati et al. [13,14]. The use of robotic assistance reduces procedure times, but at a higher cost and with less accessibility. In our study, the operating time was reduced from the ninth patient. Other studies reported the reduction in operating time started from the 15th patient in endoscopic mastectomies [28], and from the 10th [19] to the 13th if robotic assistance is used [27].

The average length of stay is somewhat excessive in our study, longer than for C—NSM. We explain this by the innovative nature of the technique and the desire for prolonged monitoring in this setting. This LOS is now shorter.

The complication rates in our study appeared to be comparable to those observed in the literature. We observed only one partial superficial NAC ischemia (5 %) compared with 8.5 % for Lai et al. with video-assisted mastectomy techniques without insufflation [25]. In another case, and outside of the NAC, a tiny partial skin necrosis was secondary to an intraoperative skin burn. Insufflation seems to prevent the use of retractors by creating sufficient working space, which can have an impact on the vascularization of the skin sheath. Combined with the fact that there is no scar on the breast, this could help to limit NAC ischemia. No implant removal or conversion to open surgery was observed in these preliminary results, unlike the study about R-NSM of Sarfati et al. [14] (6.5 % and 1.4 %, respectively). The infection rate in our study (5 %) was comparable to the rate found in the comparable study about R-NSM by Sarfati et al. (6.5 % [14]).

The use of lipofilling after immediate prosthetic reconstruction mastectomy is common. [29]. The rate of lipofilling in our study appeared to be comparable to existing literature (65.7 % [30]).

Like in our study, we found a plebiscite from patients for this scarless surgery in the literature: 100 % of patients would choose the same technique for E-NSM [23] and 95 % for R-NSM [19]). In a study evaluating C—NSM with mesh, the median score evaluating the satisfaction with breast was found at 51, comparing to 54 in our study [31].

The main strength of our preliminary results in this study is that it was prospective, with a one-year follow-up carried out in all patients in the study (no patient was lost to follow-up), and supported by validated scales (EROQUOL, BREASTQ and Constant Score).

The limitations were the monocentric nature, the partial nature of these preliminary results, the small number of patients and a single specifically trained surgeon. After this feasibility study, it would be interesting to confirm the results in a multicenter study involving several investigators and a larger patient cohort.

## Conclusion

The preliminary results of this study showed that E-NSM with a monotocraft and axillary approach is technically feasible. It allowed a prepectoral prosthesis to be fitted without the use of a matrix, with low complication rates and comparable to those in the literature. The esthetic results are satisfying from both the surgeon's and the patients' point of view. These results must be confirmed in a larger cohort.

## Sources of funding received for the work

Financial support through donations from the Montpellier Reine.

## Authors' contributions

G. Rathat: study design, inclusion, writing. M. Chaumette: writing, literature review. V. Fontaine: data collection. L. Rebel: help with inclusion. C. Duflos: statistics. J. Pissarra: writing assistance. M. Duraes: proofreading.

## Disclosure of interests

The corresponding author is consultancy for Applied Medical, that's the only conflict of interest to disclose.

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