5. NEWS

several stitches, abdominal cavity contamination is prevented. This technique was named crown method because pulled-up stomach wall looks like a crown (Figure 16). Using the traction of the stitch, the resected specimen is inverted to the intragastric cavity. This technique

Figure 16. Surgeons pull up the incision line of the stomach with several stitches and pulled up stomach wall looks like a

crown.

32 Gastric Cancer - An Update

was named inverted LECS. Inverted LECS with crown method is not only useful for preventing tumor seeding into peritoneal cavity, but also for securing the visual field during the operation. The stitches are also used as a supporting tool when the incision line is closed with a laparoscopic stapling device (Figure 17). Although nonexposed endoscopic wallinversion surgery (NEWS) [26] and a combination of laparoscopic endoscopic approaches to neoplasia with a nonexposure technique (CLEAN-NET) [27] are described later as nonexposure procedures, inverted LECS with crown method has few limitations such as tumor size or tumor location in comparison with NEWS or CLEAN-NET. As such, it can make it possible

Figure 17. The stitches are also used as a supporting tool when the incision line is closed with a laparoscopic stapling

device. The Figures 16 and 17 are excerpted from Nunobe's report.

Classical LECS with crown method is an improved technique that reduces the risk of cancer cell dissemination. However, it can be difficult to completely prevent the contamination because of transmural communication during the procedure. Nonexposed endoscopic wallinversion surgery (NEWS) was first reported by Goto et al. in 2011 with the goal of minimizing transmural communication during the operation [26]. They performed NEWS in an ex vivo porcine model and described the usefulness of this procedure. By inverting the tumor into the inside of the stomach without opening the gastric lumen, complete resection with nonexposure was achieved. The procedure is as follows:

1. "Markings around a model lesion are made with electrocautery knife."

2. "A circumferential seromuscular incision is made from the outside."

3. "The muscle layer is linearly sutured at approximately 5 mm intervals with the lesion inverted into the inside."

6. CLEAN-NET

procedures are described below.

cautery knife."

A combination of laparoscopic endoscopic approaches to neoplasia with a nonexposure technique (CLEAN-NET) was first reported by Inoue et al. in [27]. This procedure also involves a nonexposure technique like NEWS, but with a difference. By preserving the continuity of the mucosa, the mucosa works as a barrier (a clean net), to prevent abdominal cavity contamination and seeding of tumor cells into the peritoneal cavity. The specimen is lifted from the peritoneal cavity, so it is retrieved laparoscopically. Inoue actively performs endoscopic and laparoscopic full-thickness resection for not only GISTs but also for early gastric cancer. The

Laparoscopic Endoscopic Cooperative Surgery: Current Status and Perspective

http://dx.doi.org/10.5772/intechopen.76983

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1. "Endoscopic markings are placed on the surrounding mucosa of the lesion with electro-

2. "The mucosal layer is fixed onto the seromuscular layer using four stay sutures."

3. "By pulling four stitches upward with laparoscopic forceps, selective seromuscular dissection outside the four stiches is performed using a laparoscopic electrocautery knife."

4. "A circumferential mucosubmucosal incision is performed from inside with electrocautery knife guided by the endoscope." These figures are excerpted from Goto's report.

He reported NEWS for three lesions (one anterior wall, one lesser curve and one posterior wall of the gastric body) using porcine stomach, and complete resection was achieved for all lesions safely and without perforation or air leakage. Nonexposure techniques such as NEWS and CLEAN-NET are adequate for SMT without ulceration as well as SMT with ulceration or even early gastric cancer. In his report, the maximal specimen size was 50 mm; however, there is a limit of removable tumor size. Because the resected tumor is removed through the pharynx by the endoscope, solid tumor such as GIST over 30 mm is thought to be difficult to retrieve.
