Transmesenteric approach for laparoscopic endoscopic cooperative surgery for a duodenal adenoma located in the third portion of the duodenum

We report our experience in a patient with adenoma located in the horizontal part of the duodenum, which was effectively treated with the transmesenteric laparoscopic endoscopic cooperative surgery (LECS) approach. This approach, which entails incising the mesentery of the colon, simplified laparoscopic access to the horizontal part of the duodenum, which was minimally mobilized. Thus, the bulb and descending part of the duodenum were fixed to the retroperitoneum, facilitating stable handling of the endoscope and enabled safe and effective excision of an adenoma located in the horizontal part of the duodenum. This approach enabled safe and effective excision of an adenoma located in the horizontal part of the duodenum. The advantages of this method include a secure field of view, lower probability of damage to large vessels, and minimizing the defect to the intestine caused by the incision.


| INTRODUCTION
Endoscopic submucosal dissection of duodenal lesions reportedly causes postoperative perforation in some patients due to issues associated with endoscope operability and a thin duodenal wall. 1 Therefore, laparoscopic and endoscopic cooperative surgery (LECS), which entails the simultaneous use of laparoscopy and endoscopy, was developed, which has found clinical application for duodenal lesions with relative safety.Herein, we report our experience in a patient with adenoma located in the horizontal part of the duodenum, which was effectively treated with the transmesenteric LECS approach, along with a detailed description of the transmesenteric approach.

| CASE PRESENTATION
The patient was a 40-year-old man, who was 177 cm tall, weighed 61 kg.Upper gastrointestinal endoscopy and contrast revealed a clearly circumscribed, flat, and protruding lesion in the horizontal part of the duodenum measuring 20 mm (Figure 1A, B).The tumor was diagnosed as an adenoma on biopsy.LECS was performed under general anesthesia.Part of the duodenum was visible through the mesentery of the colon (Figure 2A).The pedicle of the ileocolic vessels was grasped, the mesentery of the colon was incised dorsally, and dissection was performed between the mesentery of the colon and retroperitoneum using the inside approach (Figure 2B).Subsequently, the ileocolic artery and vein were taped and pulled (Figure 2C) to secure the field of view and working space (Figure 2D).Thereafter, the endoscope was inserted via the oral route, the location of the tumor was confirmed, and intraperitoneal marking was performed (Video S1).The endoscopic procedure was started from this point onward.Local injection of hyaluronic acid was administered to the mucosal tissue under endoscopic guidance (Figure 3A) and the entire tumor was excised.Subsequently, a peripheral incision was created endoscopically over the entire circumference of the tumor (Figure 3B, C).From the intraperitoneal perspective, it appeared partly perforated and a full-thickness incision was performed endoscopically up to half of the circumference (Figure 3D).Thereafter, an additional full-thickness incision was created laparoscopically and the resected tumor was placed as is, in a collection bag (Video S2).And the defect in the duodenum was sutured and closed laparoscopically (Figure 4A-C).The closed part was covered with a polyglycolic acid sheet (Figure 4D).Finally, a drain was inserted and the mesentery of the colon was sutured and closed, marking the completion of surgery (Video S3).The total operative time was 194 minutes.A small amount of perioperative bleeding was observed.The patient had a favorable postoperative course and was discharged from the hospital without complications.

| DISCUSSION
Hiki et al. developed LECS to facilitate local resection of gastric submucosal tumors, in order to avoid excessive resection and conserve gastric function. 2arious efforts have been made to prevent bacterial infection caused by the leakage of the contents of the stomach or peritoneal tumor seeding resulting from full-thickness resection (CLEAN-NET, NEWS). 3,4In contrast, the indications or surgical technique of LECS for the management of superficial non-ampullary duodenal epithelial tumor have not been established, and there is no consensually designated approach for tumors located deeper than the horizontal part with low frequency.For adenoma in the horizontal part of the duodenum, it is necessary to laparoscopically mobilize the bulb, descending part, and horizontal part of the duodenum for the cephalic approach in classical LECS. 5,6However, mobilization from the descending to the horizontal part with the Kocher maneuver renders subsequent handling of the endoscope very difficult.This is because nothing supports (holds) the endoscope since the structures supporting the duodenum are removed during the Kocher maneuver.Hence, the current approach that entails incising the mesentery of the colon (inside approach) simplifies laparoscopic access to the horizontal part of the duodenum, which is minimally mobilized.Thus, the bulb and descending part of the duodenum are fixed to the retroperitoneum, facilitating stable handling of the endoscope during the endoscopic procedure.This approach is effective for tumors situated in the descending to horizontal part of the duodenum, located on the anal side of the Vater's papilla.However, it poses challenges for duodenal tumors positioned more orally than the Vater's papilla.This method is particularly advantageous when the tumor is on the side opposite to the pancreas.If the tumor is on the anterior or posterior wall and is at a safe distance from the pancreas, adequate resection can be achieved using this technique.The light from the intraoperative endoscope illuminates the duodenum and can highlight the boundaries of the pancreas where light cannot penetrate.Conversely, if the intestinal incision extends toward the pancreatic side, or if the tumor is in close proximity to the Vater's papilla, conventional open surgery or an open transition is often the favored choice.
Assessing the location of the tumor before surgery is crucial in order to determine the suitability of this method.By administering Gastrografin contrast during endoscopy, it is possible to verify whether the tumor is located anorectally to the Vater's papilla and to ensure that the tumor is not positioned on the pancreatic side.If these two conditions are met, this method is indicated.

F
I G U R E 1 Endoscopy (A) and gastrointestinal contrast (B) showed a clearly circumscribed, flat and protruding lesion measuring 20 mm which can be seen in the horizontal part of the duodenum.F I G U R E 2 Intraoperative findings (mobilization of the duodenum).(A) The duodenum is visible through the mesentery of the colon.(B) The pedicle of the ileocolic artery and vein was grasped and the mesentery of the colon was dissected from the duodenum.(C) The pedicle of the ileocolic artery and vein was taped and pulled.(D) End of mobilization of the duodenum.

F I G U R E 3
Intraoperative endoscopic operation.(A) Local injection was administered endoscopically to the mucosal tissue.(B) A peripheral incision was created endoscopically.(C) Incision of the entire circumference was performed endoscopically.(D) A part of the incision was perforated.

F I G U R E 4
Suture and closure.(A) After extraction of the specimen.(B) All layers were closed using continuous sutures.(C) An additional suture was placed in the muscular serosa.(D) A polyglycolic acid sheet was attached.