Researchers describe a robotic, flexible endoscopy system that can be safely used to remove early-stage stomach tumors in the October issue of Clinical Gastroenterology and Hepatology.
Endoscopic submucosal dissection (ESD) is an effective technique to remove early-stage gastrointestinal tumors. However, it is difficult to master because it requires submucosal dissection from different angles, through manipulation of the endoscope, while keeping a clear view of the submucosa. A slight deviation from the submucosal plane can result in perforation.
Soo Jay Phee et al. developed a robotic system they call MASTER to reduce the technical difficulties of this procedure. They added robotic arms to a flexible endoscope, with end effectors, which included a monopolar diathermy L-shaped hook and a grasper (see below figure).
The system requires 2 operators—1 steers the endoscope while the other performs the submucosal dissection with the robotic arms.
Phee et al. performed a multi-center prospective trial of the feasibility and safety of the MASTER ESD system in 5 patients with early-stage gastric neoplasias that were limited to the mucosa.
They found that the mean submucosal dissection time was 18.6 minutes, without any perioperative complications— shorter than for similar cases performed by standard ESD techniques. Three patients were discharged from the hospital within 12 hours and 2 on the third day after the procedures. Two patients were found to have intramucosal adenocarcinoma—1 had high-grade dysplasia, 1 had low-grade dysplasia, and 1 had a hyperplastic polyp. The resection margins were clear of tumors in all 5 patients. A month later, none of the patients had residual or recurrent tumors or complications from the procedure.
The patients recruited in this study had gastric neoplasias of 1–3 cm in size, located at antrum and body. Phee et al. propose a trial to examine the feasibility, safety, and effectiveness of MASTER in patients with early-stage gastric tumors of different sizes, at different positions of the stomach.
Nonetheless, they state that this is an important milestone toward future application of robotics in endoscopy. Further advances to the system, such as development of different and swappable end effectors, will increase the functionality of the system, so it can expanded to be used in other endoluminal procedures and transluminal surgery.
In an editorial that accompanies the article, Robert Hawes and Steve Eubanks explain that several companies have made initial efforts to develop new flexible endoscopic platforms, with arms that would allow for exchangeable accessories and some degree of triangulation. None of these systems had a computer interface and all directly translated hand movements to end effectors. However, the system described by Phee et al. is a true robotic system with a computer interface to allow transmission of hand motion to the end effectors.
Debate continues among surgeons about the value of robotic procedures for patients. However, Hawes and Eubanks state that there can be little debate about advantages such as enhanced high-definition visualization, a stable visualization and working platform, and tremor-free dissection.
They point out that the endoscopists involved this study were fully trained in ESD but had limited experience with MASTER. Nonetheless, they completed the ESD quickly, compared to historical controls. Hawes and Eubanks conclude that MASTER significantly facilitates rapid and safe completion of the dissection.
Further studies are needed to determine if physicians who have limited training in current ESD techniques can be taught to do a robotic assisted ESD more easily and quickly than the standard technique. If this proves to be the case, then robotic assisted endoluminal therapies are likely to be widely adopted.
Read the article online.
Phee SJ, Reddy N, Chiu PWY, et al. Robot-assisted endoscopic submucosal dissection is effective in treating patients with early-stage gastric neoplasia. Clin Gastroenterol Hepatol 2012;10:1117-1121.
Read the accompanying editorial.
Hawes RH, Eubanks S. Robotic endoscopy: A small case series, a giant step for endoscopy. Clin Gastroenterol Hepatol 2012;10:1122-1123.