Jean Bouquet de Jolinière
A. Major1- 1Department of Gynecology Obstetrics, Cantonal Hospital, HFR, Fribourg, Switzerland
- 2Argotlab and Synlab Laboratories, Department of Pathology, Lausanne, Switzerland
The presence of tumor cells can be identified in the lymph node when metastasis has occurred from the primary cancer site into the lymph node (1) If the sentinel lymph node ganglion is negative for the presence of tumor cells at the time of histological examination, the other lymph nodes are also negative in 99% of cases. If no tumor cells are identified in the sentinel lymph node ganglion by histological examination, the other lymph nodes are also negative for the presence of tumor cells in 99% of cases. The sentinel lymph node advantageously replaces axillary dissection as a staging method in breast cancer T1 and T2 (2). Approximately 40% of breast cancers metastasize to axillary lymph nodes and metastatic extension depends on disease stage. Sentinel lymph nodes are affected in the following stages: T1a (4.3%), T1b (19.5%), T1c (23.8%), T2 (48.9%), T3 (66.7%).
Introduction
In recent years the management of breast cancer has changed considerably. One such example of this is the disappearance of great axillary curage. The study of lymph nodes has a prognostic value and guides decision making for further treatment (3–6). Examination of the sentinel lymph node has become the gold standard. Before performing axillary clearing, evidence of metastatic invasion of at least three lymph nodes is recommended. The examination of the sentinel node during surgery remains arbitrary as micro-metastases cannot be detected. The sensitivity of this technique is dependent on the sections obtained, and interpretation can be challenging for pathologists. Oftentimes, further examination in the laboratory is necessary to obtain and validate reliable results.
Sections are conditioning this examination and many pathologists and many pathologists don't want to take this responsibility. Only the laboratory examination reassures the results.
The purpose of the present article is to demonstrate how and why through a review of the current literature.
Two techniques are currently available: standard and advanced. The present article provides a review of the current literature, and discusses the advantages and disadvantages of examination during surgery of the sentinel node (7–12).
Standard Histological Analysis of the Sentinel Node
Analysis of the Sentinel Node Ganglion Have Revolutionized Breast Cancer Surgery
• Aims: detect macro metastases (>2 mm), micro metastases (0.2–2 mm). Isolated tumor cells or clusters ≤ 0.2 mm are often only detected by immunohistochemistry.
• Technical:
- Imperative: cut the ganglion every 2 mm, either vertically (small ganglion ≤ 4 mm) or transversely (ganglion> 4 mm).
- Recommended: 3 depths (minimum).
• Results: All macroscopic and micro metastases are detected.
A Brief History of Sentinel Node Examination
Surgery has always used minimally invasive techniques in order to limit associated morbidities and facilitate post-operative surgical recovery. The examination of sentinel nodes was first performed in other types of cancer, before being applied to breast cancer. Below are some examples of this:
• 1977: The sentinel node technique was developed by R.M. Cabanas to evaluate nodal extension in penile cancers.
• 1992: The sentinel node technique was applied to melanoma:
• 1993: The sentinel node technique was applied to breast cancer.
• 2013: 20 years later, there is still no standardized and universally accepted protocol for anatomo-pathology analysis of the sentinel node. But, fortunately, there are recommendations and guidelines.
Standard Analysis Techniques for the Ganglion Examination in Classical Pathology: (13)
There are some rules to follow that demonstrate how an extemporaneous examination can be arbitrary. In a standard analysis, the different sections used make it possible to examine the sentinel lymph nodes perfectly, without omitting the minimal attacks or even isolated cells. All macro and micro metastases are detected. It is necessary to make deep cuts (at least 3) on each. It is necessary to obtain thick sections.
It is then possible to evaluate: The size of the macro metastases are noted in mm and the distance to the capsule, the presence or absence of a capsular rupture, the number and size of micro metastases and their locations, at last the presence or absence of isolated tumor cells (IHC) (14–16). As previously described, each section of lymph node should not exceed 2 mm in thickness.
On each block, do make at least three deep cuts to avoid missing metastasis. On the diagrams, in red are the metastases and the lines correspond to the cuts made. The lymph node thickness is important to consider as it is the reason why the serial cuts are important (Schema Images 1, 2, 3).
Meaning of the Presence of Tumor in the Sentinel Lymph Node
The presence of tumor in the sentinel lymph node must be considered according to different stages. In case of:
• Macro metastases (picture 5): There is a high risk of axillary residual disease (other positive lymph nodes frequently observed).
• Micro metastases (picture 4): There is an axillary residual disease in 10% of patients.
• Isolated tumor cells (picture 6): Rarely associated with an axillary residual disease and have no proven prognostic significance.
These slides show how difficult and random it is to carry out in both cases an examination during surgery.
This is why an immuno-histochemical analysis makes the diagnosis more reliable. Thus, it will be the final analysis of the node that will allow a finer diagnosis and the discovery of isolated tumor cells. While this result may not affect future treatment, it has the advantage of avoiding diagnostic errors.
Sentinel Lymph Node: Advanced Histological Analysis
Immunohistochemistry
This examination facilitates the detection of isolated micro metastases and tumor cells (Ac anti cytokeratin), however false positives may be observed (benign epithelial inclusions, degenerative cells in transit, keratin-positive dendritic cells, epidermal cells in transit, etc.).
This is why the technique is become facultative according to current American clinical .society of pathology recommendations.
Molecular Biology
Technique intended for the detection of isolated tumor cells. This technique is not performed routinely. The identification of certain molecular subtypes of cancers (luminal A and luminal B), in a positive sentinel lymph node, would be associated with a higher risk of axillary residual disease and would lead to complementary lymph node dissection (17).
Surgical Technique of Sentinel Node Analysis
The currently surgical technique of sentinel node analysis is globally accepted (18–24). The patient receives an injection of colloid (TC 99M) the day before or the morning of the procedure and undergoes a lympho-scintigraphy. A card is given to the surgeon for the result.
On the day of surgery, at the beginning of the operation, the patient is anesthetized, a mini dose of blue patent is injected in peri-areolar and subcutaneously? A mini incision is made and the surgeon with a probe reads the radio activity, and looks for the blue of the ganglion (picture 9), which is removed and checked with the probe (picture 10). A noise of radioactivity is given and the piece is sent to the pathologist for the continuation of the examination.
However, it is necessary to discuss the differences between the histological and cytological analysis of a lymph sentinel node during surgery, as the results can be discordant (25).
Histological Analysis (Per-Operative) of Sentinel Lymph Node
Conventional Indications (Currently Questioned)
The challenge is how identifying the location of extemporaneous examination of the sentinel lymph node in breast cancer given that:
• Detect macro metastases (>2 mm) to perform complementary axillary dissection at the same operative stage (but macro metastases can be seen in radiology (CT/MRI) and punctured/biopsied before the operation).
• Detected micro metastases (but the presence of micro metastases is no longer a formal indication for complementary axillary lymph node dissection)
• Isolated tumor cells are not taken into account.
Technical Consider Another Word Choice Like Technique, or Method
Histologically, it is necessary to cut the lymph node every 2 mm and examine all sections extemporaneously. Particular attention must be paid to avoid using all material and allow for proper standard histological examination after fixation.
It is also necessary carrying out cytological fingerprints.
Results and Benefits
This type of examination allows either a reliable diagnosis (90% of the cases) that conditions the practice of a complementary axillary clearing. There is a variable false negative rate (0–48%), inversely proportional to the number of deep cuts performed. The reliability through cytological fingerprinting is increased. Sometimes, an immuno-histo-chemical examination can be performed. But a lengthy and difficult reading is necessary as there are many artifacts due to frozen tissue: This examination requires an experienced and specialized pathologist, who is not always accessible. Lastly, the permanent loss of part of tissue for standard histological diagnosis is a risk as it may distort the final review.
Cytological Analysis (Per-Operative) of Sentinel Lymph Node
This procedure has satisfactory specificity. Several advantages and disadvantages are described below (26, 27):
Advantages
• It allows a reliable diagnosis in 95% of the cases that condition complementary axillary dissection (28).
• The false negative rate is 5–10%.
• Rapid immuno-histochemical examination is possible (rare).
• This technique is simple and cheap.
• Importantly, there is no tissue loss, unlike histological examination.
Disadvantages
• Reading the tissues histologically during the operation is too long.
• This examination requires experience and training of the pathologist.
• Size and location of metastatic site not to be specified.
• Differentiation between macro and micro metastases is not possible.
Discussion and Literature Review
Knowledge of sentinel lymph node status remains the most powerful prognostic factor in defining the adjuvant strategy of the majority of solid tumors (29).
The difficulty of the methods described demonstrates the necessity of having an experienced pathologist to evaluate extemporaneously micro metastases or isolated metastasis cells. As proposed by the American Society of Breast Surgeons, accreditation should be given to surgeons practicing sentinel node examination in breast cancer after teaching and evaluating their technique.
The axillary dissection gives only a prognostic indication (30). The tumors being diagnosed smaller and smaller, the technique of the GS has taken its place. The adjuvant therapeutic strategies depend on its results.
Indeed, the presence of isolated tumor cells has no predictive value for residual axillary disease. No pejorative prognostic value either the presence of micro metastases is associated in 10–12% of cases with residual axillary disease. No significant prognostic difference in terms of overall survival and survival without recurrence (Acozog 2011). Therefore no complementary axillary clearing is use full (28).
At the Lyon South Hospital Center (29), one study evaluated the value of lymph node and axillary sentinel node (GS) biopsy in 243 invasive breast cancers with non-palpable lymph nodes, according to the colorimetric (Evans blue and patent blue) and combined (colorimetric + technetium 99 m colloid) techniques. The sentinel lymph node (GS) detection rate was 225/243 (92.59%), with the colorimetric method of 89.94% and the combined method of 100%. The false negative rate was less than 2%.
In the literature, it is interesting to note that no per- unsure of meaning of per operative examination has been carried out to date.
The incidence of ganglion metastasis was studied in the GS in multiple-section HPS staining. If this examination was negative, the GS was examined using immunohistochemistry. The other axillary lymph nodes were examined in HPS on two sections. They are fixed in Bouin's liquid. After 24 h, they were cut into sections of 3 mm after having been included in paraffin and stained with hematoxylin phloxin saffron (HPS). If no metastasis was found in HPS, immunohistochemistry (IHC) was performed with cytokeratin KL1 (1/100 Immuno-tech dilution) on 4 mm thick sections fixed with the immuno-peroxidase method amplified by the streptavidin complex/Biotone and revealed by diaminobenzidine (Kit L. Sab. Dako®, Denmark)(29).
There must be not only a standardization of the technique of lymphatic marking, but also of the anatomo -pathological study of the GS, in particular by immunohistochemistry. It should be emphasized that for specialized teams, whatever the technique used, the results obtained are very similar with detection rates of GS>90%.
In their text, the literature is explicit. The false negative rate (FN) is certainly the most important element to consider for this diagnostic test (number of axillary adenopathies p N1 when the GS is p N0/total p N1). For the American Society of Breast Surgeons for a GS rate of 85%, the acceptable FN rate is ≤ 5% (40). In their study, the rate of FN is 7/92 (7.60%), but if FN is removed macroscopically obviously malignant for the surgeon where the detection of the GS no longer has interest, the rate of FN Is acceptable (1/91–1.09%) -Unsure of meaning here. Currently, the FN rate varies from one team to another, but it must be emphasized that in trained teams it is less than 10% (11, 24, 31). Using the colorimetric method, Giuliano has a FN rate of 0% (31). Miltemburg of the 1,335 cases with a GS identification rate of 83.6%, have an FN rate of 5.1% (30). In a study by Viale et al., the negative predictive value was 90.3 to 100% with a concordance between GS histology and axillary node status from 97.1 to 100% (45). These figures are found by Albertini (32).
By multiplying the sections on the axillary lymph nodes (multiple serial sections) compared to a conventional method, the rate of p N1 is increased by an average of 9% (from 4 to more than 20%). By an immuno-histo-chemical study, the p N1 level due to micro metastases increases by an average of 20% (8 to more than 40%). This is why we are not in favor of the intraoperative examination of the GS. This examination may result in loss of material and may not permit an accurate immuno-histochemical study. The extemporaneous examination of the GS only seems justified if the surgeon suspects metastasis due to macroscopic examination of this ganglion (27). The false negative rate of the extemporaneous examination of the GS is 18% for Hill et al., 17% for Veronesi (11) and 13% for Van Diest (33). False negatives are due to micro metastases detected only by serial ganglion sections or by immunohistochemistry.
In their study, the total number of micro metastases was 23/85 p N1 sentinel lymph node, with a detection rate of only 9% in IHC. For Giuliano, the micro metastases axillary level was 7.7%, 9% for Lineham et al., 10.6%, for Cox (34) and 17% for Veronesi (11, 31). In a study by Dowlasthahi, this rate was very high for small tumors as it reached 58% (35). But 50% of micro metastatic p N1 is invaded by less than ten malignant cells (34). Thus, by extensive GS study by immunohistochemistry, the number of patients with stage II cancer is increased compared with conventional histopathological examination. It is therefore necessary to remove the current controversy over the prognostic value of these micro metastases detected by immunohistochemistry and molecular biology in order to define an appropriate strategy (34–37).
In our study, the risk of leaving invaded lymph nodes in the armpit would be 35/85 (41.17%). For Veronesi (11) it would be 62 and 43% for Albertini (32).The greater the size of the micro metastases in the sentinel lymph node (GS), the greater the risk of non-GS lymph node involvement (28). It is therefore necessary to define a maximum size of micro metastases for which the risk of p N1 outside the GS is zero and does not require an axillary dissection.
Conclusion
It is difficult to accurately identify micro metastases in the breast sentinel lymph node by extemporaneous examination. Therefore, the authors of the present article avoid performing it.
Should we continue to do extemporaneous examinations on sentinel lymph nodes?
Is it necessary to perform a lymph node dissection in the presence of micro metastases?
According to updated international guidelines, 3 invaded lymph nodes are required to perform an axillary clearing. Lastly, there is a current discussion regarding the ablation under local anesthesia of the GS at the same time as diagnostic biopsy in order to allow multidisciplinary teams to take an ad hoc decision and avoid two surgical interventions.
Author Contributions
All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.
Conflict of Interest Statement
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
The reviewer LL and the handling editor declared their shared affiliation at the time of the review.
References
1. Coutant C, Rouzier R, Olivier C, Bezu C. Modèles prédictifsd'envahissement des ganglions non sentinelles en cas de métastases des ganglons sentinelles dans le cancer du sein. Gynecol Obstet Fertil. (2009) 37:160–6. doi: 10.1016/j.gyobfe.2008.09.021
2. Erb KM, Julian TB. Completion of axillary dissection for a positive sentinel node: necessary or not ? Curr Oncol Rep. (2009) 11:15–20. doi: 10.1007/s11912-009-0004-8
3. Ogasawara Y, Yoshitomi S, Sato S, Doihara H. Clinical signifiance of preoperative lymphoscintigraphy for sentinel lymph node biopsy in breast cancer. J Surg Res. (2008) 148:191–6. doi: 10.1016/j.jss.2007.10.022
4. Tulpin L, Morel O, Akerman G, Malartic C. Intérêt de la lymphoscintigraphie dans la procédure du ganglion sentinelle en cancérologie mammaire. Gynecol Obstet Fertil. (2008) 36:808–14. doi: 10.1016/j.gyobfe.2008.06.006
5. Rodier JF, Velten M, Wilt M, Martel P. Prospective mullticentric randomized study comparing periareolar and peritumoral injection of radiotracer and blue dye for the detection of sentinel lymph node in breast sparing procedures. J Clin Oncol. (2007) 25:3664–9. doi: 10.1200/JCO.2006.08.4228
6. Wang L, Yu JM, Wang YS, Zuo WS. Preoperative lymphoscintigraphy predicts the successful identification but is not necessary in sentinel lymph nodes biopsy in breast cancer. Ann Surg Oncol. (2007) 14:2215–20. doi: 10.1245/s10434-007-9418-4
7. Zavagno G, De Salvo GL, Scalco G, Bozza F, Barutta L. A Randomized clinical trial on sentinel lymph node biopsy versus axillary lymph node dissection in breast cancer: results of the Sentinella/GIVOM trial. Ann Surg. (2008) 247:207–13. doi: 10.1097/SLA.0b013e31812e6a73
8. Zavagno G, Del Bianco P, Koussis H, Artioli G, Carraro P. Clinical impact of false-negative sentinels lymph nodes in breast cancer. Eur J Surg Oncol. (2008) 34:620–5. doi: 10.1016/j.ejso.2007.07.003
9. Langer I, Guller U, Berclaz G, Koechli OR, Schaer G. Morbidity of sentinel lymph node biopsy (SLN) alone versus SLN and completion axillary lymph node dissection after breast cancer surgery: a prospective Swiss multicenter study on 659 patients. Ann Surg. (2007) 245:452–61. doi: 10.1097/01.sla.0000245472.47748.ec
10. Purushotham AD, Macmillan RD, Wishart GC. Advances in axillary surgery for breast cancer: time for a tailored approach. Eur J Surg Oncol. (2005) 31: 929–31. doi: 10.1016/j.ejso.2005.07.008
11. Veronesi U, Paganelli G, Galimberti V, Viale G, Zurrida S. Sentinel node biopsy to avoid axillary dissection in breast cancer with clinically negative lymph nodes. Lancet (1997) 349:1864–7. doi: 10.1016/S0140-6736(97)01004-0
12. Mansel RE, Fallowfield L, Kissin M, Goyal A, Newcombe RG. Randomized multicenter trial of sentinel node biopsy versus standard axillary treatment in operable breast cancer: The ALMANAC Trial. J Natl Cancer Inst. (2006) 98:599–609. doi: 10.1093/jnci/djj158
13. Straver ME, Meijnen P, van Tienhoven G, van de Velde CJ, Mansel RE. Sentinel node identification rate and nodal involvement in the EORTC 10981-22023 AMAROS trial. Ann Surg Oncol. (2010) 17:1854–61. doi: 10.1245/s10434-010-0945-z
14. Houvenaeghel G, Nos C, Giard S, Mignotte H. A nomogram predictive of non-sentinel lymph node involvement in breast cancer patients with a sentinel lymph node micrometastasis. Eur J Surg Oncol. (2009) 35:690–5. doi: 10.1016/j.ejso.2008.10.003
15. Reed J, Rosman M, Verbanac KM, Mannie A. Prognostic implications of isolated tumor cells and micrometastases in sentinel nodes of patients with invasive breast cancer: 10-year analysis of patients enrolled in the prospective East Carolina University/Anne Arrundel Medical Center Sentinel Node Multicenter Study. J Am Coll Surg. (2009) 208:333–40. doi: 10.1016/j.jamcollsurg.2008.10.036
16. Weaver DL. The prognostic importance of isolated tumor cell clusters and micrometastases in sentinel lymph nodes. Cancer Investig. (2009) 27:121–8. doi: 10.1080/07357900802572029
17. Wang M, Zhou W, Zhao Y, Xia T, Zha X, Ding Q, et al. A novel finding of sentinel lymphatic channels in early stage breast cancer patients: which may influence detection rate and false-negative rate of sentinel lymph node biopsy. PLoS ONE (2012) 7:e51226. doi: 10.1371/journal.pone.0051226
18. Suami H, Pan WR, Mann GB, Taylor GI. The lymphatic anatomy of the breast and its implications for sentinel lymph node biopsy: a human cadaver study. Ann Surg Oncol. (2008) 15:863–71. doi: 10.1245/s10434-007-9709-9
19. Sappey MPC. Anatomie, Physiologie, Pathologie des vaisseaux Lymphatiques consideres chez L'homme at les Vertebre. Paris: A. Delahaye and E. Lecrosnier. (1874)
20. Kern KA. Sentinel lymph node mapping in breast cancer using subareolar injection of blue dye. J Am Coll Surg. (1999)189:539–45. doi: 10.1016/S1072-7515(99)00200-8
21. Kern KA, Rosenberg RJ. Preoperative lymphoscintigraphy during lymphatic mapping for breast cancer: improved sentinel node imaging using subareolar injection of technetium 99m sulfur colloid. J Am Coll Surg. (2000)191:479–89. doi: 10.1016/S1072-7515(00)00720-1
22. Kern KA. Lymphoscintigraphic anatomy of sentinel lymphatic channels after subareolar injection of Technetium 99m sulfur colloid. J Am Coll Surg. (2001)193:601–8. doi: 10.1016/S1072-7515(01)01068-7
23. Bajen MT, Benitez A, Mora J, Ricart Y, Ferran N. Subdermal re-injection: a method to increase surgical detection of the sentinel node in breast cancer without increasing the false-negative rate. Eur J Nucl Med Mol Imaging (2006) 33:338–43. doi: 10.1007/s00259-005-1931-8
24. Krag DN, Anderson SJ, Julian TB, Brown AM, Harlow SP. Technical outcomes of sentinel-lymph-node resection and conventional axillary-lymph-node dissection in patients with clinically node-negative breast cancer: results from the NSABP B-32 randomised phase III trial. Lancet Oncol. (2007) 8:881–8. doi: 10.1016/S1470-2045(07)70278-4
25. Goyal A, Newcombe RG, Chhabra A, Mansel RE. Factors affecting failed localisation and false-negative rates of sentinel node biopsy in breast cancer–results of the ALMANAC validation phase. Breast Cancer Res Treat. (2006) 99:203–8. doi: 10.1007/s10549-006-9192-1
26. Miltenburg DM, Miller C, Karamlous TB, Brunicard I. Meta-analysis of sentinel node in breast cancer. Association for Academic Surgery. Abstract: November 20, 1998; Seattle.
27. Ku NN. Pathologic examination of sentinel lymph nodes in breast cancer. Surg Oncol Clin North Am. (1999) 8:469–79. doi: 10.1016/S1055-3207(18)30197-2
28. Chu KU, Turner RR, Hansen NM, Brennan MB, Bilchick A, Giuliano A. Do all patients with sentinel node metastasis from breast carcinoma need complete axillary node dissection? Ann Surg. (1999) 229:536–41. doi: 10.1097/00000658-199904000-00013
29. Bobin JY, Spirito C, Isaac S, Zinzindohoue C, Joualee A, Khaled M, et al. Lymph node mapping and axillary sentinel lymph node biopsy in 243 invasive breast cancers with no palpable nodes. The Lyon-Sud hospital experience. Ann Chir. (2000) 125, 861–70. doi: 10.1016/S0003-3944(00)00007-9
30. Abner AL, Collins L, Peiro G, Recht A, Come S, Shulman LN. Correlation of tumor size and axillary lymph node involment with prognosis in patients with T1 breast carcinoma. Cancer (1998) 93:2502–8. doi: 10.1002/(SICI)1097-0142(19981215)83:12<2502::AID-CNCR14>3.0.CO;2-I
31. Lyman GH, Giuliano AE, Somerfield MR, Benson AB 3rd, Bodurka DC. American Society of Clinical Oncology guideline recommendations for sentinel lymph node biopsy in early-stage breast cancer. J Clin Oncol. (2005) 23:7703–20. doi: 10.1200/JCO.2005.08.001
32. Albertini J, Lyman J, Cox GH, Yeatman C, Balducci T, Ku LN. Lymphatic mapping and sentinel node biopsy in the patient with breast cancer. JAMA (1996) 276:1818–22. doi: 10.1001/jama.1996.03540220042028
33. Van Diest PJ, Torrenga H, Borgstein PJ, Pijpers R, Bleichrodt RP, Rahusen FD, Meijer S. Reliability of intraoperative frozen section and imprint cytological of sentinel lymph nodes in breast cancer. Histopathology (1999) 35:14–8. doi: 10.1046/j.1365-2559.1999.00667.x
34. Allred DC, Elledge RM. Caution concerning micrometastatic carcinoma in sentinel lymph nodes. Cancer (1999) 86:905–7.
35. Dowlatshahi K, Fan M, Bloom KJ, Spitz DJ, Patel S, Snider HC. Occult metastases in sentinel lymph nodes of patients with early stage breast carcinoma. A preliminary study. Cancer (1999) 86:990–6.
36. Yeatman TJ, Cox CE. The significance of breast cancer lymph node micrometastases. Surg Oncol Clinic North Am. (1999) 8:481–96. doi: 10.1016/S1055-3207(18)30198-4
Keywords: sentinel node, examination during operation, breast cancer, immuno-histo chemistry, axillary curage
Citation: Bouquet de Jolinière J, Major A, Khomsi F, Ben Ali N, Guillou L and Feki A (2018) The Sentinel Lymph Node in Breast Cancer: Problems Posed by Examination During Surgery. A Review of Current Literature and Management. Front. Surg. 5:56. doi: 10.3389/fsurg.2018.00056
Received: 12 December 2017; Accepted: 16 August 2018;
Published: 14 November 2018.
Edited by:
Patrice Mathevet, Lausanne University Hospital (CHUV), SwitzerlandReviewed by:
Salim Alfred Bassil, Al-Arz Hospital, LebanonLoïc Lelievre, Lausanne University Hospital (CHUV), Switzerland
Copyright © 2018 Bouquet de Jolinière, Major, Khomsi, Ben Ali, Guillou and Feki. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Jean Bouquet de Jolinière, jean.bouquetdejoliniere@h-fr.ch