The Application of Rigid and Flexible Mediastinoscopy in Esophagectomy: Our Experience and a New Technology

doi:10.21203/rs.3.rs-525371/v1

Download PDF

Research Article

The Application of Rigid and Flexible Mediastinoscopy in Esophagectomy: Our Experience and a New Technology

https://doi.org/10.21203/rs.3.rs-525371/v1

This work is licensed under a CC BY 4.0 License

Journal Publication

published 07 Aug, 2021

Read the published version in World Journal of Surgical Oncology →

You are reading this latest preprint version

Background: To avoid the inconvenience of triangulation among various rigid operating instruments in Mediastinoscopy-Assisted Esophagectomy，we invent a new technique: Using a flexible endoscope to mobilize thoracic esophagus and dissect mediastinal lymph nodes through the left cervical incision. In this study, we introduce our long-term experience and demonstrate this new technique.

Methods: 29 patients with early esophageal cancer underwent Mediastinoscopy-Assisted Esophagectomy in our hospital from June 2018 to September 2020. Among them, 12 patients used flexible mediastinoscopy, and 17 patients used conventional rigid mediastinoscopy and instruments to observe their therapeutic effect.

Results: There were no significant differences between the two groups in gender, average age, body mass index, incidence of adverse reactions, bleeding volume and postoperative hospital stay. The operation time of flexible mediastinoscopy group was significantly shorter than that of rigid mediastinoscopy group (192.9±13.0 vs 246.8±6.9 min, p<0.01). The number of lymph nodes removed by flexible endoscopy was significantly more than that of rigid endoscopy (8.5±0.6 vs 6.0±0.3, P<0.01). Postoperative follow-up was completed for all patients, and the average follow-up time was 11.6±7.2 months. During the follow-up period, no recurrence or death was observed.

Conclusions: Mediastinoscopy-Assisted Esophagectomy is an effective way to treat early esophageal cancer. The application of flexible mediastinoscopy provides more convenience and better stability. It can facilitate the operation of the surgeon and lymph node dissection, which proved to be a feasible technology.

Surgery

Oncology

Flexible Mediastinoscopy. Mediastinoscopy-Assisted Esophagectomy MAE. Flexible Endoscopy. Minimally Invasive Esophagectomy MIE. Early esophageal cancer

Numerous literatures indicate that mediastinoscopy treatment of esophageal cancer is a feasible operation since Mediastinoscopy-Assisted Esophagectomy (MAE) was proposed in 1990[1, 2]. MAE is an advanced surgical technique, but due to its rigid characteristics and the limitation of other rigid equipment (ultrasonic scalpel, suction device, etc.) required in a narrow space during the surgery, it is inconvenient and only used as an alternative to conventional surgery in early esophageal cancer patients with cardiopulmonary dysfunction. In addition, the almost horizontal angle has limitations in mediastinal lymphadenectomy.

In order to reduce the damage to the mediastinum caused by the equipment and its rigid characteristic, and perform lymphadenectomy more conveniently, we have developed a new surgical technique: Flexible Mediastinoscopy. The flexible endoscope is used for the operation of thoracic esophagus and lymphadenectomy. So far, there is no report on the clinical application of this technology.

Patients

From January 2018 to December 2020, 29 early esophageal cancer patients (Tis-T1) were incapable of endoscopic treatment due to extensive lesions or the deeper infiltration. So they underwent MAE in our hospital, and 12 patients among them underwent surgery with flexible mediastinoscopy. After explaining the difference between the two operations, the attending doctor determined the operating instruments according to the patients’ own choice.

All the patients came from the same outpatient department. Rigid mediastinoscopy, laparoscopy and gastroesophageal anastomosis were performed by the same surgical team. Flexible mediastinoscopy was operated by experienced endoscopists under the guidance of thoracic surgeons.

Surgical technique

According to standard surgical procedures, mediastinoscopy and laparoscopy were performed at the same time. Dissociated the stomach under laparoscopy; converged with the mediastinoscopy; made a tubular stomach; performed the gastroesophageal anastomosis in the neck. Mediastinal drainage tube and enteral nutrition tube were indwelled after operation. Mediastinoscopy was performed through a 5 cm long transverse incision on the left clavicle. After we fully dissociated and severed the cervical esophagus, the distal esophagus resection edge was connected to a rubber tube for traction to facilitate the dissection of the upper esophagus. Generally, chest CT scan was performed on the fourth day after surgery, and the mediastinal drainage tube was pulled out when the CT showed no massive pleural effusion. The enteral nutrition tube was left for 1 month after leaving the hospital.

Rigid Mediastinoscopy:

A sealed Lap-Protector was inserted into the cervical incision. CO2 gas was blown in to provide a stable surgical field (Pressure 15mmHg, Flow 20L/h), and then we carefully pushed the operating instrument into the mediastinum cavity from the left side of esophagus (Fig. 1a). Surgery on the neck required the cooperation of the surgeon, assistant, and another doctor holding the mediastinoscope. The assistant mainly used the long retractor to assist in exposing the operating vision (Fig. 1b). Dissecting the esophagus clockwise downwards, the left recurrent laryngeal nerve, posterior thoracic duct and important vessels should be protected or ligated. The dissection was mainly assisted by the LaparoSonic CoagulatingShears (LCS) and duckbill pliers. The azygos arch and bronchial arteries were exposed by LCS at the right side of the esophagus. The anterior tracheoesophageal ligament was directly dissociated, and trachea bifurcation/hilar lymph nodes were visible. We separated the visible lymph nodes by blunt dissection or hemostatic clips. Due to the limitation of the angle, we dissociated the esophagus to the inferior pulmonary vein level and merged with the laparoscope.

Flexible Mediastinoscopy:

This operation was a joint effort of the skilled endoscopists and the experienced thoracic surgeons. The neck incision was not sealed and placed with a conventional lap-protector. A cap-based flexible mediastinoscope entered the mediastinum in this way. The neck operation required two doctors, the endoscopist performing the operation, and the assistant required to assist in the movement of the flexible endoscope (Fig. 2). The flexible mediastinoscopy group also required CO2 insufflation. Articulatory hook or IT Knife was used for the endoscopic esophageal dissection (Fig. 3). A small amount of bleeding could be controlled by electrocoagulation snares. We flushed some water to provide a clear surgical field. Articulator grasper blunt dissection and IT knife were combined for lymphadenectomy (Fig. 4). Under endoscopy, we could confirm the carina, pulmonary vein, superior vena cava and lymph nodes at every station. The carbon dioxide expanded the space in the mediastinal cavity, that made the tiny structures around the aortic arch, such as nerves, bronchial arteries, and lymphatic vessels, clearly visible. The flexible mediastinoscopy dissociated downward to the diaphragmatic hiatus and converges with the laparoscope.

Routine abdominal operation under laparoscopy: Gastric dissociation and abdominal lymphadenectomy were performed. After combining the mediastinum, esophagus was extracted through subxiphoid incision. Made a tubular stomach. Performed the gastroesophageal anastomosis in the neck. Placed a mediastinal drainage tube through subxiphoid incision.

Data collection and analyses

Clinical data was collected from the medical records, and the patients were followed up for 1 month after surgery, and then every 3–6 months. Assessed perioperative variables included operation time, intraoperative blood loss, number of thoracic lymph nodes, postoperative complications (recurrent laryngeal nerve injury, chylothorax, and pleural effusion), and postoperative hospital stay.

Statistical analysis was performed by SPSS software, version 22.0. All p values reported were two-sided, and p < 0.05 indicates statistical significance. Continuous variables were expressed as means ± standard deviation and compared by t test, whereas categorical variables were evaluated with Fisher’s exact test or the χ² test.

In this study, 12 patients underwent flexible mediastinoscopy and another 17 patients underwent traditional rigid endoscopy and instruments. Postoperative follow-up data were available for all patients. The following parameters were assessed: Age, Sex Ratio and Body Mass Index (BMI), and Tumor T Staging. These parameters had no significant difference between the two groups (Table 1).

All the patients underwent esophagectomy successfully. No serious complications such as tearing of azygos vein or artery and tracheal injury were observed in both groups. The operating time of the flexible mediastinoscopy group was significantly shorter than that of the traditional rigid mediastinoscopy group (192.9 ± 13.0 vs 246.8 ± 6.9 min, p < 0.01). As for the number of enucleated thoracic lymph nodes, flexible mediastinoscopy had an obvious advantage (8.5 ± 2.2 vs 6.0 ± 1.4, P < 0.01). There was no significant difference in intraoperative blood loss between the two groups (114.2 ± 17.5 vs 111.7 ± 16.0 ml, P > 0.05). In the rigid mediastinoscopy group, 1 patient had mild chylothorax and 1 patient had mild recurrent laryngeal nerve injury. However, they were cured with conservative treatment (11.8%). No recurrent laryngeal nerve injury was observed in the flexible mediastinoscopy group. 2 cases required catheter drainage because of postoperative pleural effusion (16.7%). No severe delayed hemorrhage, severe pulmonary infection or anastomotic fistula was observed in the two groups. There was no significant difference in postoperative hospital stay between the two groups (7.6 ± 1.3 vs 6.9 ± 1.2 days, P > 0.05). All patients completed postoperative follow-up, with an average follow-up time of 11.6 ± 7.2 months. As a new technique, the flexible mediastinoscopy developed late, and the mean follow-up time was shorter than that of the rigid mediastinoscopy group (8.9 ± 3.2 vs13.5 ± 8.5 months). No tumor recurrence was observed in either group during the follow-up period (Table 2).

Table 1

Comparison of baseline demographics between the two groups
Variables	Category	F group(n = 12)	R group(n = 17)	P
Age (years)	Range	41–78	41–75	0.46
	Mean ± SD	58.8 ± 10.3	61.9 ± 11.7
Gender	Female	5	9	0.71
	Male	7	8
BMI (kg/m2)	Range	20–29	21–29	0.32
	Mean ± SD	24.3 ± 3.1	25.4 ± 2.8
T staging	Tis	6	5	0.23
	T1a	4	7
	T1b	2	5

Table 2

Comparison of clinical data between the two groups
Variables	F group(n = 12)	R group(n = 17)	P
Operating details
Operating time (min)	192.9 ± 13.0	246.8 ± 6.9	< 0.001
Intraoperative blood loss(ml)	114.2 ± 17.5	111.7 ± 16.0	0.69
Number of thoracic lymph nodes	8.5 ± 2.2	6.0 ± 1.4	0.002
Postoperative Complications	11.8% VS 16.7%
Pleural effusion	2	0
Recurrent laryngeal nerve injury	0	1
Chylothorax	0	1
Postoperative hospital stay(days)	7.6 ± 1.3	6.9 ± 1.2	0.15
Follow-up time (month)	8.9 ± 3.2	13.5 ± 8.5

The 3rd day after surgery, all the patients performed chest CT to see if there was lung infection or pleural effusion. When there was no chylous exudation and drainage volume < 50 ml/day, the mediastinal drainage tube was removed. Enteral nutrition was given on the 4th day after surgery. That’s to say, the patients used a syringe to inject food into the gastrointestinal tract through a nasal feeding tube. After the nutrition tube was indwelling for 1 month, when the patients had upper gastrointestinal angiography and that showed no anastomotic stenosis or anastomotic leakage, the gastrointestinal nutrition tube was pulled out and the patient began to eat by mouth. Neither group of patients had undergone radiotherapy or chemotherapy during treatment.

Natural Orifice Transluminal Endoscopic surgery (NOTEs) is a unique emerging surgical concept that extends flexible endoscopy beyond the intestinal wall. At present, the application of NOTEs technology in the abdominal cavity has developed rapidly and has entered the stage of clinical operation. However, due to the existence of vital organs and the possibility of more severe complications in the mediastinal cavity, the application is mostly at the exploratory stage [3], and there are still technical limitations through natural orifices such as esophagus and trachea. The incision, closure and positioning are still urgent problems to be solved [4]. The mediastinum has higher requirements for sterility. The surgery is performed through non-sterile holes such as the gastrointestinal tract, so NOTEs approach sterile environment does not meet the requirements to some extent.

NOTEs technology pursues no surface incision. Numerous animal experiments have been conducted to realize this concept, and various pathways are on trial [3, 5–7]. However, for the patients with esophageal cancer who are not feasible for ESD/EMR and need total esophagectomy and gastrointestinal reconstruction, it may be available in the future. Studies have shown that flexible endoscopy can provide good vision during mediastinal exploration and can perform basic operations such as pleural biopsy. In addition, due to its flexibility, you can go wherever you want [3, 8]. Besides, it has been reported that the flexible endoscopy can create a connective tissue tunnel to the distal esophagus to perform Heller Myotomy [9]. The compact connective tissue tunnel has safe propulsion and stability for the endoscope [10]. Combining previous literatures with NOTEs concept, in our operation, advanced endoscopic techniques are used to assist surgical operation and replace rigid mediastinoscopy and instruments. The subxiphoid incision can indwell a mediastinal drainage tube to prevent mediastinal emphysema and serious infection to a certain extent. More advanced technology to minimize surgical trauma and alleviate patient suffering.

Flexible endoscopy may have absolute advantages in the mediastinum, such as the ability to identify avascular embryonic tissue planes and conform to the tortuous mediastinal structure. Shorter operation time and undifferentiated intraoperative blood loss can prove the advantages. The lymphadenectomy under previous animal experiments requires the endoscopic ultrasound-guidance, positioning or the support of technologies such as nano-carbon [11–14]. In our clinical application, we have enough experience in MAE. A low level of positive pressure carbon dioxide insufflation could provide ample exposure space, which is not a cumbersome operation.

The flexible mediastinoscopy can reach anywhere close enough through the endoscopic magnification. Blunt and sharp separation complete the lymphadenectomy jointly. Instead of lymph node polymer, select a single lymph node dissect. Some reports state that it is a safe strategy to dissect the left recurrent laryngeal nerve lymph nodes (RLN LNs) during esophageal cancer surgery under the flexible laparoscope [15]. Our results and experience also verify that it is safe and effective to perform this operation through articulator grasper and IT knife in the context of neuro-denseness. The transparent cap on the front can reduce the damage to the adjacent mediastinal structure theoretically and provide a more stable operating vision. In comparison, conventional mediastinoscopy requires some additional auxiliary rigid instruments to expose the surgical space. In the narrow space, it is not only necessary to overcome the triangular position of rigid instruments, but also to overcome the influence of breathing movement. For rigid instruments, it is difficult even impossible to access to the distant esophagus and mediastinum. It is hard to reach the level of inferior pulmonary vein.

Due to the LCS and trachea's nearly parallel angle and the poor visual field, it is not easy to dissociate the subcarinal lymph nodes. In contrast, since positioning the trachea is the easiest in the narrow endoscopic vision and the operational port is flexible, obviously the flexible mediastinoscopy is more suitable.

However, the risk of postoperative pleural effusion in the flexible mediastinoscopy group was higher than that in the conventional mediastinoscopy group. Our conjecture is that we were relatively unfamiliar with the esophageal outer boundary initially, which was caused by the injury of pleura, and it is proved by the fact that the latter 7 patients did not have such complications. Clear fluid drained from pleural canals, no bacterial infection found in hydrothorax culture, and no severe mediastinal infection found in postoperative CT, all of this proved that our aseptic operating environment was qualified.

So far, the indications and contraindications for the MAE are still controversial, and there is no comprehensive and recognized standard. Many comparative studies have demonstrated the feasibility of MAE, and in the course of long-term follow-up, the treatment effect is similar to transthoracic esophagectomy [2, 16, 17]. MAE avoids transthoracic operations, and it can be considered as a more friendly technique for patients with poor cardiac and pulmonary function, or a history of pleural disease [17]. It doesn’t need to change position. Besides, the operation time is relatively shortened. Early studies reported numerous instruments and methods to improve MAE, but the standard technology has not yet established [18]. Conventional mediastinoscopy has not been widely used due to the limited vision and operational inconveniences. Besides, it is just regarded as a palliative surgical treatment for the patients with significant tumor invasion or mediastinal lymph nodes involvement. We believe that the flexible mediastinoscopy could make MAE indications more extensive to some extent. As for the advanced tumors, we are making relevant attempts.

It is essential to be familiar with the esophageal anatomy and physiology in the application of flexible endoscopic techniques. The cardiothoracic surgeon's unfamiliarity with flexible endoscopes will undoubtedly slow the transition from research protocols to clinical applications in thoracic surgery. In our operation, the flexible mediastinoscopy is carried out with the joint efforts of particularly experienced endoscopists and under thoracic surgeons with rich MAE experience. We believe that both flexible and rigid mediastinoscopy can safely achieve the operation of the thoracic esophagus, while the flexible mediastinoscopy has better advantages due to its less aggressiveness, its stability in a narrow space, and its flexibility. It provides more possibilities for MAE. We proposed the concept of flexible mediastinoscopy. We believe that, with the development of more innovative endoscopic instruments, the flexible mediastinoscopy might have great application value.

Based on the NOTEs, we unveiled a new technology, proposed the concept of flexible mediastinoscopy, and applied it to the operation of thoracic esophagus and lymphadenectomy, which proved to be a feasible technique that could be transformed into an effective tool of thoracic surgery.

Authors’ Contributions

Chun-Li Wu: drafting and revising manuscript. Bo Dong: treated the patients and analysis data. Chun-Yang Zhang, Bin Wu and Yin-liang Sheng: Designed and participated in this surgery. Ya-Fei Liu and Guan-Chao Ye: Attend to the patients and figures processing. Lu Han; Shi-Hao Li: coordination. Yu Qi: Provided the overall supervision and the production of the manuscript.

Ethical considerations

The research was carried out in accordance with the World Medical Association Declaration of Helsinki. All the subjects provided written informed consent and we obtained informed consent from all the subjects. It was carried out with the approval of the Ethics Committee of the First Affiliated Hospital of Zhengzhou University. The methods were carried out strictly in accordance with institutional policies and relevant guidelines and regulations.

Conflicts of Interest

The authors declare that there are no conflicts of interest.

Tokairin Y, Nakajima Y, Kawada K, Hoshino A, Okada T, Ryotokuji T, Ogo T, Okuda M, Kume Y, Kawamura Y, Yamaguchi K, Nagai K, Kawano T, Kinugasa Y. A feasibility study of mediastinoscopic radical esophagectomy for thoracic esophageal cancer from the viewpoint of the dissected mediastinal lymph nodes validated with thoracoscopic procedure: a prospective clinical trial. Esophagus: official journal of the Japan Esophageal Society. 2019;16:214–9.
Feng MX, Wang H, Zhang Y, Tan LJ, Xu ZL. W. Qun. Minimally invasive esophagectomy for esophageal squamous cell carcinoma: a case-control study of thoracoscope versus mediastinoscope assistance. Surgical endoscopy. 2012;26:1573–8.
Gee DW, Willingham FF, Lauwers GY, Brugge WR. D. W. Rattner. Natural orifice transesophageal mediastinoscopy and thoracoscopy: a survival series in swine. Surgical endoscopy. 2008;22:2117–22.
Fritscher-Ravens A, Patel K, Ghanbari A, Kahle E, von Herbay A, Fritscher T, Niemann H. P. Koehler. Natural orifice transluminal endoscopic surgery (NOTES) in the mediastinum: long-term survival animal experiments in transesophageal access, including minor surgical procedures. Endoscopy. 2007;39:870–5.
Lima E, Henriques-Coelho T, Rolanda C, Pêgo JM, Silva D, Carvalho JL. J. Correia-Pinto. Transvesical thoracoscopy: a natural orifice translumenal endoscopic approach for thoracic surgery. Surgical endoscopy. 2007;21:854–8.
Yang C, Chu Y, Wu YC, Hsieh MJ, Lu MS, Liu CY, Yuan HC, Liu YH, Ko PJ. H. P. Liu. The lateral decubitus position improves transoral endoscopic access to the posterior aspects of the thorax. Surgical endoscopy. 2012;26:2988–92.
Khereba M, Thiffault V, Goudie E, Tahiri M, Hadjeres R, Razmpoosh M, Ferraro P. M. Liberman. Transtracheal thoracic natural orifice transluminal endoscopic surgery (NOTES) in a swine model. Surgical endoscopy. 2016;30:783–8.
Willingham FF, Gee DW, Lauwers GY, Brugge WR. D. W. Rattner. Natural orifice transesophageal mediastinoscopy and thoracoscopy. Surgical endoscopy. 2008;22:1042–7.
Spaun GO, Dunst CM, Arnold BN, Martinec DV, Cassera MA. L. L. Swanström. Transcervical heller myotomy using flexible endoscopy. Journal of gastrointestinal surgery: official journal of the Society for Surgery of the Alimentary Tract. 2010;14:1902–9.
Ikeda Y, Niimi M, Kan S, Sasaki Y, Shatari T, Takami H. S. Kodaira. Mediastinoscopic esophagectomy using carbon dioxide insufflation via the neck approach. Surgery. 2001;129:504–6.
Spaun GO, Dunst CM, Martinec DV, Arnold BN, Owens M. L. L. Swanstrom. Mediastinal surgery in connective tissue tunnels using flexible endoscopy. Surgical endoscopy. 2010;24:2120–7.
Liu BR, Ahmed MR, He D, Zhao L, Yang W, Zhang X, Shi Y, Zhou Y, Zhang D, Chen Y, Cao Z, He D, Yuan Y. D. Li. Endoscopic Mediastinal Lymph Node Identification and Resection Using Carbon Nanoparticles in a Porcine Model. Gastroenterology. 2019;156:1250–2.
Swanstrom LL, Dunst CM. G. O. Spaun. Future Applications of Flexible Endoscopy in Esophageal Surgery. J Gastrointest Surg. 2010;14:127–32.
Fritscher-Ravens A, Cuming T, Olagbaiye F, Holland C, Milla P, Seehusen F, Hadeler KG, Arlt A. K. Mannur. Endoscopic transesophageal vs. thoracoscopic removal of mediastinal lymph nodes: a prospective randomized trial in a long term animal survival model. Endoscopy. 2011;43:1090–6.
Fujiwara H, Shiozaki A, Konishi H, Kosuga T, Komatsu S, Ichikawa D, Okamoto K. E. Otsuji. Single-Port Mediastinoscopic Lymphadenectomy Along the Left Recurrent Laryngeal Nerve. Ann Thorac Surg. 2015;100:1115–7.
Koide N, Takeuchi D, Suzuki A, Miyagawa S. Mediastinoscopy-assisted esophagectomy for esophageal cancer in patients with serious comorbidities. Surg Today. 2012;42:127–34.
Wang QY, Tan LJ, Feng MX, Zhang XY, Zhang L, Jiang NQ, Wang ZL. Video-assisted mediastinoscopic resection compared with video-assisted thoracoscopic surgery in patients with esophageal cancer. Journal of thoracic disease. 2014;6:663–7.
Mimatsu K, Oida T, Kawasaki A, Kano H, Fukino N, Kuboi Y, Amano S. A novel technique of mediastinoscopy-assisted esophagectomy with a flexible laparoscope and endoscopic overtube. Surgical laparoscopy, endoscopy & percutaneous techniques 2010; 20: e44-46.

Download PDF

Journal Publication

published 07 Aug, 2021

Read the published version in World Journal of Surgical Oncology →

Editorial decision: Major Revision
02 Jul, 2021
Review #2 received at journal
22 Jun, 2021
Review #1 received at journal
22 Jun, 2021
Reviewer #3 agreed at journal
18 Jun, 2021
Reviewer #2 agreed at journal
17 Jun, 2021
Reviews received at journal
04 Jun, 2021
Reviewers invited by journal
04 Jun, 2021
Reviewer #1 agreed at journal
03 Jun, 2021
Editor assigned by journal
25 May, 2021
Submission checks completed at journal
24 May, 2021
Editor invited by journal
24 May, 2021
First submitted to journal
13 May, 2021

You are reading this latest preprint version

The Application of Rigid and Flexible Mediastinoscopy in Esophagectomy: Our Experience and a New Technology

Status:

Journal Publication

Version 1

Abstract

Figures

Introduction

Methods

Results

Discussion

Conclusions

Declarations

References

Supplementary Files

Status:

Journal Publication

Version 1