DOI: https://doi.org/10.21203/rs.3.rs-1983639/v1
Background: Endoscopic submucosal dissection（ESD）has the advantages of high complete resection rate, less trauma and higher safety than open surgery. However, ESD has high technical requirements and is difficult to operate, especially when submucosal dissection fails to fully expose the submucosa. To create a good operational field of vision and achieve accurate cutting, a variety of endoscopic assisted traction methods have emerged. Our study team has invented a new traction method, that is, snare combined with rubber band assisted ESD in the treatment of early gastric cancer.
Methods: Retrospective study was performed in 35 patients diagnosed as having early gastric cancer and received ESD assisted by snare and rubber band method from January 2016 to December 2018.The en bloc excision rate, procedure time, complication rate were analyzed.
Results: All lesions received en bloc resection. The lesion size ranged ２～6ｃｍ.The median procedure time was 30min (ranging 25～45min). There was no bleeding or perforation occurred during and after the procedure.
Conclusion: Snare-rubber band assisted traction method can provide good vision during the ESD procedure for early gastric cancer, and increase resection efficiency, reduce the operation time and complication rate.
Endoscopic submucosal dissection(ESD) is a new technique for the treatment of early cancers of the digestive tract, which has the advantages of high complete resection rate, less trauma and higher safety than open surgery. However, ESD has high technical requirements and is difficult to operate, especially when submucosal dissection fails to fully expose the submucosa, which increases the operation difficulty, time, postoperative bleeding and perforation complications[1–3]。In order to create a good operational field of vision and achieve accurate cutting, a variety of endoscopic assisted traction methods have emerged, such as oral floss traction, snare traction, metal clip-elastic band combined traction[4–7]。Inspired by these assisted traction technologies, our department started the innovative ESD treatment of early gastric cancer with the new methods of snare combined with rubber ring assisted traction in January 2016, and the efficacy was satisfactory, as reported below.
Patients data: Between January 2016 and December 2018, a total of 35 patients with lesions diagnosed histologically as early gastric cancer were consecutively enrolled. In the process of intraoperative submucosal dissection, the visual field was not fully exposed, so 14 cases of female patients and 21 cases of male patients were treated with ESD assisted by Snare and rubber band combined traction. The age ranges from 42 years to 76 years, with an average age of 59 years. All patients signed informed consent for endoscopic treatment before the ESD procedure, and fasting and water deprivation before ESD.
Apparatus and equipment： GIFQ260J、GIF-HQ290 gastroscope( Olympus Optical Co. Ltd., Tokyo, Japan ), ERBE ICC-200 high frequency electric knife, CO2 air pump, olympus Dual knife, IT knife，olympus SD-210U-10 snare，1.5cm diameter and 1mm thickness rubber band, olympus HX-610-135 hemostatic clip.
Operation methods
(1) To expose the lesion, the boundary of the lesion was determined endoscopic staining and magnifying endoscopy, and the mark was made at 0.5cm away from the lesion boundary with Dual knife. (2) Glycerol fructose with epinephrine were injected into the submucosal layer of the lesion to fully elevate the lesion.(3) The transparent cap was fixed at the front end of the endoscope, and Dual knife was inserted into the endoscope to reach the lesion, and the peripheral mucosa or part of the mucosa was opened with a Dual knife or IT knife to separate the lesion along the submucosa, and the endoscope was withdrawn when the visual field exposure was difficult during the dissection.(4) The rubber band is inserted into the snare and fixed with the snare, and the snare is tightened outside of the transparent cap. The snare is 1-3mm away from the end of the transparent cap, and the assistant holds the handle of the snare. After re-entering the endoscope to reach the lesion of dissection, release and push out the entrapment device, tighten the entrapment device moderately, adjust the handle of the entrapment device and place the rubber band at the edge of the incision mucosa. The metal clip releaser enters stomach through the endoscopic passage, opens the metal clip to draw the rubber band, and then fixes the rubber band to the open mucosal edge of the lesion. The surgeon or assistant can pushes or pulls the snare device to fully expose the submucosa, continues submucosal injection and dissection, and finally removes the lesion completely. The lesion and snare device exit together with the endoscope, flattens out in vitro, and the fine needle is fixed on the foam plate for pathological examination.
Pathological evaluation: To determine whether the tumor was removed at one time and whether the tumor body was intact. If there is no residual tumor tissue, the tumor is considered to be en bloc resected under endoscope. The main pathological examination indicators of the specimen were pathological type, differentiation degree, infiltration depth, horizontal and vertical incisions, and whether there was lymphatic and vascular infiltration.
Postoperative management and follow-up: All cases were treated with proton pump inhibitors postoperatively and hemostatic drugs were routinely used. Fasting for 1-2 days after operation. To observe whether there was bleeding in the digestive tract, abdominal pain and abdominal distension. If there were no special conditions, fluid diet was allowed on the 3rd day postoperatively. Oral proton pump inhibitors were administered for 2 months after discharge. Three months, six months and twelve months after the operation, gastroscopy was repeated.
All the 35 cases were treated with en bloc resection at one time, and there were no complications such as uncontrolled bleeding and perforation during the ESD procedure. The lesions had a diameter of 2-6cm, the operation time was 25- 45min, and the average time was 30min. Pathological results showed that among the lesions of early gastric cancer, 2 cases had low-grade intraepithelial neoplasia, 19 had high-grade intraepithelial neoplasia, and 14 had high-grade intraepithelial neoplasia with focal canceration. All excised lesions had negative incised margins without vascular infiltration. The short-term follow-up patients had good wound healing without tumor recurrence and long-term postoperative complications of gastric stricture.
ESD is effective in the treatment of early gastric cancer and precancerous lesions. The key to the success of ESD surgery is submucosal dissection. Good exposure of the operation visual field during submucosal dissection can shorten the operation time and significantly reduce the occurrence of bleeding, perforation and residual tumor tissue. In order to better expose the operational field of vision, various clinical attempts have been made, such as internal traction, external floss or snare traction, magnetic traction, etc. Each method has its limitations. For example, floss traction method, the texture of floss is hard, thin, there may be potential cutting damage to the surrounding tissue; Floss can only pull the lesion towards the oral direction, but cannot push the lesion in the anal direction. In the snare traction method, the snare is rigidly connected with the lesion, which is easy to tear the lesion during the operation, resulting in lesion damage and affecting the postoperative pathological evaluation. Excessive tension caused by excessive tightening of snare can cause leison damage, even bleeding and perforation[1, 8, 9]。
The key points of the snare and rubber band combined assisted traction method: (1) timing of use: in the process of conventional ESD, when the submucosa is not fully exposed, the traction method can be considered. The rubber band connected with the snare was clipped on the lesion at the cut edge with a metal clip, and the snare was pulled to the oral side or pushed to the anal side according to the location of the lesion and the degree of submucosal exposure. (2) The extracorporeal snare and the rubber band should be firmly connected to prevent the rubber band from escaping during the process of conveying to the stomach. The snare connected with the rubber band is tightened on the outside of the transparent cap, but not on the top of the transparent cap, so as not to increase the difficulty of releasing the snare device. (3) When the snare tip reached the vicinity of the lesion, the snare was released carefully and slowly to avoid damage to the lesion. Under endoscopic observation, the metal ring at the front end of the snare was received into the plastic sheath tube, and during tighten the snare metal ring to prevent it from trapping the lesion and surrounding mucosa.(4) During the process of metal clip clamping, the rubber band was moderately pulled so that the middle point of the distal end of the rubber band was clipped on the mucosal surface of the lesion.(5) Although the snare used as traction is connected with the lesion by elastic rubber band ring, it is still not allowed to exert too much force in the process of pulling or pushing, so as to avoid the lesion damage.
The advantages of the snare combined with the rubber band traction method: (1)The required materials are readily available, the snare and metal clips are the common instruments in endoscopic central, and the rubber bands are cheap and available for sale. The operation method is simple and easy to master. (2) The trap appliance has certain hardness, can play a supporting role; The sheath tube of the snare is smooth and the diameter is larger than that of all kinds of traction line equipment, so that there is no cutting damage to the surrounding mucosa; The elastic action of the rubber band makes the pulling force relatively constant, which makes it easier to fully expose the surgical field and reduce the damage to the lesion.(3) Through the aid of the snare, the pull and push traction method can be realized, with flexible operation and stronger practicability. (4) During the process of assisted traction, the traction position of the distal end of snare can be adjusted appropriately through the endoscope, which is more conducive to exposing the surgical field of vision. (5) ESD may operate by only one person. The trap can maintain the current traction state without extra force after pushing or pulling to the appropriate position, so there is no need to be equipped with assistant traction. (6) The excised lesion can be taken out of the stomach directly through the snare-rubber band-metal clip.
In conclusion, the new technique of traction assisted by the snare device and rubber band can provide a good surgical field of view, shorten the operation time, and reduce the incidence of bleeding, perforation and other complications in the ESD of early upper gastrointestinal cancer. For beginners can reduce the difficulty of operation, improve the operator's treatment confidence.
Endoscopic submucosal dissection
Ethics approval and consent to participate
The participant in our study provided signed informed consent. This study was approved by the ethics committee of the Zhengzhou University.
Consent for publication Not applicable
Availability of data and material: The data and material used during the current study are available from the corresponding author.
Competing interests
All the authors have no possible competing interests
Funding
Not applicable
Authors contributions
Author contributions: Bai B, Li Z，Mao CS,，Kuang SL and Zhou BX contributed equally to this work; Bai B designed the research study; Mao CS performed the case search; Li Z analyzed the data; Kuang SL and Zhou BX wrote the manuscript; all authors have read and approved the final manuscript.nuscript.
Acknowledgements
We would like to acknowledge the reviewers for their helpful comments on this paper.