Portal de Periódicos da CAPES

What we want for ESD is a second hand! Traction method

2013; Elsevier BV; Volume: 78; Issue: 2 Linguagem: Inglês

10.1016/j.gie.2013.04.192

1097-6779

Norio Fukami,

Esophageal and GI Pathology

Endoscopic submucosal dissection (ESD) has enabled unlimited size resection of the GI mucosa. This technique has also been applied to the removal of submucosal lesions effectively and safely while minimizing morbidity. Still, this special technique demands a high level of skill from the endoscopist and carries risks for serious adverse events. Physicians need to be trained by experts before performing their own procedures to carry out ESD proficiently, effectively, and safely.Surgeons use 2 hands for open abdominal surgery, and they currently expand their skill sets to include hand-assisted laparoscopic surgery, laparoscopic surgery through multiple or single ports, and robotic surgery. In other words, there is a significant benefit to using countertraction by the other hand in all surgical methods, exposing the area of surgical field and cutting plane clearly for swift operation. Intraluminal endoscopic surgery is very limited in this sense.Endoscopists use the accessory channel of the endoscope as a conduit to the operative field. Only a single accessory can be used at a time. Therefore, the history of advanced endoscopic procedures is composed mostly of the improvement of the accessories specifically designed for such procedures.Over the years, ESD has called for modifications of technique with devices to improve the process and the outcome of the procedure, such as cushion fluids, specialty knives, and countertraction methods.Countertraction to assist ESD (ie, the surgeon's other hand in flexible endoscopic procedures) has been attempted with various methods, and this can be very helpful. Simple countertraction is currently achieved by applying pressure on to the tissue with a transparent attachment hood or cap placed on to the endoscope tip. Although it works for providing modest countertraction, its effect is not optimal. Some of these attempts have been clip-with-thread traction (clip-with-line method); alongside-the-scope, percutaneous, or intraluminal traction methods; (eg, forceps traction method, magnet anchor method, spring device method, and second-endoscope method); and the double-channel endoscope method.1Oyama T. Counter traction makes endoscopic submucosal dissection easier.Clin Endosc. 2012; 45: 375-378Crossref PubMed Scopus (110) Google Scholar, 2Okamoto K. Okamura S. Muguruma N. et al.Endoscopic submucosal dissection for early gastric cancer using a cross-counter technique.Surg Endosc. 2012; 26: 3676-3681Crossref PubMed Scopus (18) Google Scholar, 3Jeon W.J. You I.Y. Chae H.B. et al.A new technique for gastric endoscopic submucosal dissection: peroral traction-assisted endoscopic submucosal dissection.Gastrointest Endosc. 2009; 69: 29-33Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar, 4Imaeda H. Hosoe N. Ida Y. et al.Novel technique of endoscopic submucosal dissection by using external forceps for early rectal cancer (with videos).Gastrointest Endosc. 2012; 75: 1253-1257Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar, 5Kondo H. Gotoda T. Ono H. et al.Percutaneous traction-assisted EMR by using an insulation-tipped electrosurgical knife for early stage gastric cancer.Gastrointest Endosc. 2004; 59: 284-288Abstract Full Text Full Text PDF PubMed Scopus (92) Google Scholar, 6Kobayashi T. Gotohda T. Tamakawa K. et al.Magnetic anchor for more effective endoscopic mucosal resection.Jpn J Clin Oncol. 2004; 34: 118-123Crossref PubMed Scopus (75) Google Scholar, 7Gotoda T. Oda I. Tamakawa K. et al.Prospective clinical trial of magnetic-anchor-guided endoscopic submucosal dissection for large early gastric cancer (with videos).Gastrointest Endosc. 2009; 69: 10-15Abstract Full Text Full Text PDF PubMed Scopus (116) Google Scholar, 8Kuwano H. Mochiki E. Asao T. et al.Double endoscopic intraluminal operation for upper digestive tract diseases: proposal of a novel procedure.Ann Surg. 2004; 239: 22-27Crossref PubMed Scopus (24) Google Scholar, 9Fusaroli P. Grillo A. Zanarini S. et al.Usefulness of a second endoscopic arm to improve therapeutic endoscopy in the lower gastrointestinal tract. Preliminary experience - a case series.Endoscopy. 2009; 41: 997-1000Crossref PubMed Scopus (7) Google Scholar, 10Mochiki E. Yanai M. Toyomasu Y. et al.Clinical outcomes of double endoscopic intralumenal surgery for early gastric cancer.Surg Endosc. 2010; 24: 631-636Crossref PubMed Scopus (11) Google Scholar, 11Sakurazawa N. Kato S. Miyashita M. et al.An innovative technique for endoscopic submucosal dissection of early gastric cancer using a new spring device.Endoscopy. 2009; 41: 929-933Crossref PubMed Scopus (20) Google ScholarThis traction assistance is far more important for difficult ESD in specific locations, such as the upper part of the stomach or with healed ulcer scars, and probably for the expansion of the ESD indication to submucosal tumors (SMT).12Toyokawa T. Inaba T. Omote S. et al.Risk factors for perforation and delayed bleeding associated with endoscopic submucosal dissection for early gastric neoplasms: analysis of 1123 lesions.J Gastroenterol Hepatol. 2012; 27: 907-912Crossref PubMed Scopus (119) Google Scholar, 13Yoo J.H. Shin S.J. Lee K.M. et al.Risk factors for perforations associated with endoscopic submucosal dissection in gastric lesions: emphasis on perforation type.Surg Endosc. 2012; 26: 2456-2464Crossref PubMed Scopus (48) Google Scholar, 14Jeong J.Y. Oh Y.H. Yu Y.H. et al.Does submucosal fibrosis affect the results of endoscopic submucosal dissection of early gastric tumors?.Gastrointest Endosc. 2012; 76: 59-66Abstract Full Text Full Text PDF PubMed Scopus (41) Google ScholarIn this issue, 2 publications shed insight on how traction with a second endoscope can help in special situations where ESD can be very challenging. Higuchi et al15Higuchi K. Tanabe S. Azuma M. et al.Double-endoscope endoscopic submucosal dissection for the treatment of early gastric cancer accompanied by an ulcer scar (with video).Gastrointest Endosc. 2013; 78: 266-273Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar report the findings in a series of patients who underwent gastric ESD for lesions with ulcer scars. Countertraction was provided by a second small-caliber endoscope with forceps inserted alongside the conventional upper endoscope (double-scope ESD). They disconnected the second endoscope from a light source once adequate grasping of the edge of the tissue was obtained, making this procedure more applicable to common practice, wherein a single light source is used in each procedure room. Double-scope ESD was feasible without the use of an overtube, in contrast with a previous report.8Kuwano H. Mochiki E. Asao T. et al.Double endoscopic intraluminal operation for upper digestive tract diseases: proposal of a novel procedure.Ann Surg. 2004; 239: 22-27Crossref PubMed Scopus (24) Google Scholar With countertraction, all 30 lesions with ulcer scars underwent en bloc resection (100%), which was better than in the compared historical control group (89%). Cutting into the lesions or specimens occurs because of the technical difficulty caused by poor lifting or inadequate separation between mucosa and muscularis propria resulting from fibrosis. This mishap did occur less frequently with traction (7% compared with 35%). Although it is not relevant to clinical outcome, this shows that countertraction does increase the feasibility of resection of lesions with fibrosis. The resection time appeared shorter but was not statistically significant (80 minutes vs 101 minutes with lesions of similar size, P = .22). The authors admit that a limitation was the retrospective nature of the study, and there was a crossover to double-scope ESD from conventional ESD, making the overall resection time longer. This report also did not include the lesions at difficult locations (upper gastric body/greater curvature, fornix), and it potentially underestimated the benefits of this technique.Another report, by Fujii et al,16Fujii L. Onkendi E.O. Bingener-Casey J. et al.Dual-scope endoscopic deep dissection of proximal gastric tumors (with video).Gastrointest Endosc. 2013; 78: 365-369Abstract Full Text Full Text PDF PubMed Scopus (9) Google Scholar addresses the feasibility and potential benefits of an additional endoscope that applies countertraction (dual-scope deep dissection) to facilitate the resection of SMT at the gastroesophageal junction (GEJ), which can be technically challenging. Combined laparoscopic and endoscopic or laparoscopic transgastric approaches have been reported for the treatment of SMT at this location to avoid gastrectomy or esophagectomy.17Tagaya N. Mikami H. Kogure H. et al.Laparoscopic intragastric stapled resection of gastric submucosal tumors located near the esophagogastric junction.Surg Endosc. 2002; 16: 177-179Crossref PubMed Scopus (81) Google Scholar, 18Granger S.R. Rollins M.D. Mulvihill S.J. et al.Lessons learned from laparoscopic treatment of gastric and gastroesophageal junction stromal cell tumors.Surg Endosc. 2006; 20: 1299-1304Crossref PubMed Scopus (40) Google Scholar, 19Song K.Y. Kim S.N. Park C.H. Tailored-approach of laparoscopic wedge resection for treatment of submucosal tumor near the esophagogastric junction.Surg Endosc. 2007; 21: 2272-2276Crossref PubMed Scopus (49) Google Scholar, 20Shim J.H. Lee H.H. Yoo H.M. et al.Intragastric approach for submucosal tumors located near the Z-line: a hybrid laparoscopic and endoscopic technique.J Surg Oncol. 2011; 104: 312-315Crossref PubMed Scopus (33) Google Scholar Nevertheless, a surgical approach is more invasive than a solely endoscopic approach. To complete endoscopic treatment for SMT at the GEJ, these authors have used a dual-scope approach. Countertraction was provided by the second small-caliber endoscope by a snare capturing the endoloop placed over the tumor. Four cases with this technique were reported, and all large tumors (2-6 cm; median 3.25 cm) were removed successfully, with procedure times of 190 to 390 minutes. There was one case of perforation, which needed laparoscopic surgical closure but had a good clinical outcome. The procedure time was significantly longer than in other large case series, which suggests that there may be a significant learning curve for the ESD procedure for SMT at the GEJ and that it would be increasingly difficult as tumors become larger.21Li Q.L. Yao L.Q. Zhou P.H. et al.Submucosal tumors of the esophagogastric junction originating from the muscularis propria layer: a large study of endoscopic submucosal dissection (with video).Gastrointest Endosc. 2012; 75: 1153-1158Abstract Full Text Full Text PDF PubMed Scopus (92) Google ScholarBoth reports state that there was no significant interendoscope interference despite the side-by-side endoscopic position.How can we best achieve countertraction? The traditional double-channel endoscope does not operate as 2 hands because both instruments passed through the accessory channels move along with the tip of the endoscope, and the double-channel endoscope does not allow adequate freedom to provide stable countertraction. To address this issue, a prototype endoscope (“R-scope”) was invented and tested.22Yonezawa J. Kaise M. Sumiyama K. et al.A novel double-channel therapeutic endoscope (“R-scope”) facilitates endoscopic submucosal dissection of superficial gastric neoplasms.Endoscopy. 2006; 38: 1011-1015Crossref PubMed Scopus (74) Google Scholar, 23Neuhaus H. Costamagna G. Deviere J. et al.Endoscopic submucosal dissection (ESD) of early neoplastic gastric lesions using a new double-channel endoscope (the “R-scope”).Endoscopy. 2006; 38: 1016-1023Crossref PubMed Scopus (119) Google Scholar, 24Lee S.H. Gromski M.A. Derevianko A. et al.Efficacy of a prototype endoscope with two deflecting working channels for endoscopic submucosal dissection: a prospective, comparative, ex vivo study.Gastrointest Endosc. 2010; 72: 155-160Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar This R-scope had 2 independent movable channels directing perpendicular directions, one of which was to provide countertraction. Even though the concept was good, this endoscope required a significant learning period to enable proficiency in its use. Additionally, it was difficult to use at a retroflexed position; thus, it was difficult to use for certain locations.Later, to mimic a surgical approach with 2 hands, a new multitasking platform was developed and compared with the double-channel endoscope for endoscopic full-thickness resection in an ex vivo animal model.25Ikeda K. Sumiyama K. Tajiri H. et al.Evaluation of a new multitasking platform for endoscopic full-thickness resection.Gastrointest Endosc. 2011; 73: 117-122Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar This completely different and innovative platform performed well within a large gastric lumen. However, it needs further refinement with additional features and dedicated accessory devices to be clinically useful. Robotic-enhanced endosurgical system had been tested in ex vivo models as well as in live pigs. Its feasibility was proven for gastric ESD and its human trial is in progress. A recently developed endoscopic suturing device was used to create traction by a “pulley technique” to facilitate tissue removal of gastric mucosa by the ESD technique in an animal model.26Ho K.Y. Phee S.J. Shabbir A. et al.Endoscopic submucosal dissection of gastric lesions by using a Master and Slave Transluminal Endoscopic Robot (MASTER).Gastrointest Endosc. 2010; 72: 593-599Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar Reports of a new endoscopic approach to the resection of SMT without countertraction have also been published.27Wang Z. Phee S.J. Lomanto D. et al.Endoscopic submucosal dissection of gastric lesions by using a master and slave transluminal endoscopic robot: an animal survival study.Endoscopy. 2012; 44: 690-694Crossref PubMed Scopus (50) Google Scholar, 28Rieder E. Makris K.I. Martinec D.V. et al.The suture-pulley method for endolumenal triangulation in endoscopic submucosal dissection.Endoscopy. 2011; 43 (UCTN:E319–E320)PubMed Google Scholar, 29Inoue H. Ikeda H. Hosoya T. et al.Submucosal endoscopic tumor resection for subepithelial tumors in the esophagus and cardia.Endoscopy. 2012; 44: 225-230Crossref PubMed Scopus (181) Google Scholar, 30Lee C.K. Lee S.H. Chung I.K. et al.Endoscopic full-thickness resection of a gastric subepithelial tumor by using the submucosal tunnel technique with the patient under conscious sedation (with video).Gastrointest Endosc. 2012; 75: 457-459Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar, 31Gong W. Xiong Y. Zhi F. et al.Preliminary experience of endoscopic submucosal tunnel dissection for upper gastrointestinal submucosal tumors.Endoscopy. 2012; 44: 231-235Crossref PubMed Scopus (92) Google Scholar Submucosal tunneling is first used to access the tumor, and the tumor is removed “under the mucosa” within the intestinal wall. This approach to the resection of SMT needs further study comparing it with conventional ESD or countertraction-assisted ESD to validate its concept, benefit, and feasibility for larger tumors or those at various locations.We are in an exciting era when new and innovative ideas for techniques and endoscopic equipment are developed to treat tumors in the GI tract. An additional “hand” would immensely facilitate the endoscopic resection procedure while reducing technical difficulty, and would certainly be helpful for physicians who are starting to learn the ESD procedure. Endoscopic submucosal dissection (ESD) has enabled unlimited size resection of the GI mucosa. This technique has also been applied to the removal of submucosal lesions effectively and safely while minimizing morbidity. Still, this special technique demands a high level of skill from the endoscopist and carries risks for serious adverse events. Physicians need to be trained by experts before performing their own procedures to carry out ESD proficiently, effectively, and safely. Surgeons use 2 hands for open abdominal surgery, and they currently expand their skill sets to include hand-assisted laparoscopic surgery, laparoscopic surgery through multiple or single ports, and robotic surgery. In other words, there is a significant benefit to using countertraction by the other hand in all surgical methods, exposing the area of surgical field and cutting plane clearly for swift operation. Intraluminal endoscopic surgery is very limited in this sense. Endoscopists use the accessory channel of the endoscope as a conduit to the operative field. Only a single accessory can be used at a time. Therefore, the history of advanced endoscopic procedures is composed mostly of the improvement of the accessories specifically designed for such procedures. Over the years, ESD has called for modifications of technique with devices to improve the process and the outcome of the procedure, such as cushion fluids, specialty knives, and countertraction methods. Countertraction to assist ESD (ie, the surgeon's other hand in flexible endoscopic procedures) has been attempted with various methods, and this can be very helpful. Simple countertraction is currently achieved by applying pressure on to the tissue with a transparent attachment hood or cap placed on to the endoscope tip. Although it works for providing modest countertraction, its effect is not optimal. Some of these attempts have been clip-with-thread traction (clip-with-line method); alongside-the-scope, percutaneous, or intraluminal traction methods; (eg, forceps traction method, magnet anchor method, spring device method, and second-endoscope method); and the double-channel endoscope method.1Oyama T. Counter traction makes endoscopic submucosal dissection easier.Clin Endosc. 2012; 45: 375-378Crossref PubMed Scopus (110) Google Scholar, 2Okamoto K. Okamura S. Muguruma N. et al.Endoscopic submucosal dissection for early gastric cancer using a cross-counter technique.Surg Endosc. 2012; 26: 3676-3681Crossref PubMed Scopus (18) Google Scholar, 3Jeon W.J. You I.Y. Chae H.B. et al.A new technique for gastric endoscopic submucosal dissection: peroral traction-assisted endoscopic submucosal dissection.Gastrointest Endosc. 2009; 69: 29-33Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar, 4Imaeda H. Hosoe N. Ida Y. et al.Novel technique of endoscopic submucosal dissection by using external forceps for early rectal cancer (with videos).Gastrointest Endosc. 2012; 75: 1253-1257Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar, 5Kondo H. Gotoda T. Ono H. et al.Percutaneous traction-assisted EMR by using an insulation-tipped electrosurgical knife for early stage gastric cancer.Gastrointest Endosc. 2004; 59: 284-288Abstract Full Text Full Text PDF PubMed Scopus (92) Google Scholar, 6Kobayashi T. Gotohda T. Tamakawa K. et al.Magnetic anchor for more effective endoscopic mucosal resection.Jpn J Clin Oncol. 2004; 34: 118-123Crossref PubMed Scopus (75) Google Scholar, 7Gotoda T. Oda I. Tamakawa K. et al.Prospective clinical trial of magnetic-anchor-guided endoscopic submucosal dissection for large early gastric cancer (with videos).Gastrointest Endosc. 2009; 69: 10-15Abstract Full Text Full Text PDF PubMed Scopus (116) Google Scholar, 8Kuwano H. Mochiki E. Asao T. et al.Double endoscopic intraluminal operation for upper digestive tract diseases: proposal of a novel procedure.Ann Surg. 2004; 239: 22-27Crossref PubMed Scopus (24) Google Scholar, 9Fusaroli P. Grillo A. Zanarini S. et al.Usefulness of a second endoscopic arm to improve therapeutic endoscopy in the lower gastrointestinal tract. Preliminary experience - a case series.Endoscopy. 2009; 41: 997-1000Crossref PubMed Scopus (7) Google Scholar, 10Mochiki E. Yanai M. Toyomasu Y. et al.Clinical outcomes of double endoscopic intralumenal surgery for early gastric cancer.Surg Endosc. 2010; 24: 631-636Crossref PubMed Scopus (11) Google Scholar, 11Sakurazawa N. Kato S. Miyashita M. et al.An innovative technique for endoscopic submucosal dissection of early gastric cancer using a new spring device.Endoscopy. 2009; 41: 929-933Crossref PubMed Scopus (20) Google Scholar This traction assistance is far more important for difficult ESD in specific locations, such as the upper part of the stomach or with healed ulcer scars, and probably for the expansion of the ESD indication to submucosal tumors (SMT).12Toyokawa T. Inaba T. Omote S. et al.Risk factors for perforation and delayed bleeding associated with endoscopic submucosal dissection for early gastric neoplasms: analysis of 1123 lesions.J Gastroenterol Hepatol. 2012; 27: 907-912Crossref PubMed Scopus (119) Google Scholar, 13Yoo J.H. Shin S.J. Lee K.M. et al.Risk factors for perforations associated with endoscopic submucosal dissection in gastric lesions: emphasis on perforation type.Surg Endosc. 2012; 26: 2456-2464Crossref PubMed Scopus (48) Google Scholar, 14Jeong J.Y. Oh Y.H. Yu Y.H. et al.Does submucosal fibrosis affect the results of endoscopic submucosal dissection of early gastric tumors?.Gastrointest Endosc. 2012; 76: 59-66Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar In this issue, 2 publications shed insight on how traction with a second endoscope can help in special situations where ESD can be very challenging. Higuchi et al15Higuchi K. Tanabe S. Azuma M. et al.Double-endoscope endoscopic submucosal dissection for the treatment of early gastric cancer accompanied by an ulcer scar (with video).Gastrointest Endosc. 2013; 78: 266-273Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar report the findings in a series of patients who underwent gastric ESD for lesions with ulcer scars. Countertraction was provided by a second small-caliber endoscope with forceps inserted alongside the conventional upper endoscope (double-scope ESD). They disconnected the second endoscope from a light source once adequate grasping of the edge of the tissue was obtained, making this procedure more applicable to common practice, wherein a single light source is used in each procedure room. Double-scope ESD was feasible without the use of an overtube, in contrast with a previous report.8Kuwano H. Mochiki E. Asao T. et al.Double endoscopic intraluminal operation for upper digestive tract diseases: proposal of a novel procedure.Ann Surg. 2004; 239: 22-27Crossref PubMed Scopus (24) Google Scholar With countertraction, all 30 lesions with ulcer scars underwent en bloc resection (100%), which was better than in the compared historical control group (89%). Cutting into the lesions or specimens occurs because of the technical difficulty caused by poor lifting or inadequate separation between mucosa and muscularis propria resulting from fibrosis. This mishap did occur less frequently with traction (7% compared with 35%). Although it is not relevant to clinical outcome, this shows that countertraction does increase the feasibility of resection of lesions with fibrosis. The resection time appeared shorter but was not statistically significant (80 minutes vs 101 minutes with lesions of similar size, P = .22). The authors admit that a limitation was the retrospective nature of the study, and there was a crossover to double-scope ESD from conventional ESD, making the overall resection time longer. This report also did not include the lesions at difficult locations (upper gastric body/greater curvature, fornix), and it potentially underestimated the benefits of this technique. Another report, by Fujii et al,16Fujii L. Onkendi E.O. Bingener-Casey J. et al.Dual-scope endoscopic deep dissection of proximal gastric tumors (with video).Gastrointest Endosc. 2013; 78: 365-369Abstract Full Text Full Text PDF PubMed Scopus (9) Google Scholar addresses the feasibility and potential benefits of an additional endoscope that applies countertraction (dual-scope deep dissection) to facilitate the resection of SMT at the gastroesophageal junction (GEJ), which can be technically challenging. Combined laparoscopic and endoscopic or laparoscopic transgastric approaches have been reported for the treatment of SMT at this location to avoid gastrectomy or esophagectomy.17Tagaya N. Mikami H. Kogure H. et al.Laparoscopic intragastric stapled resection of gastric submucosal tumors located near the esophagogastric junction.Surg Endosc. 2002; 16: 177-179Crossref PubMed Scopus (81) Google Scholar, 18Granger S.R. Rollins M.D. Mulvihill S.J. et al.Lessons learned from laparoscopic treatment of gastric and gastroesophageal junction stromal cell tumors.Surg Endosc. 2006; 20: 1299-1304Crossref PubMed Scopus (40) Google Scholar, 19Song K.Y. Kim S.N. Park C.H. Tailored-approach of laparoscopic wedge resection for treatment of submucosal tumor near the esophagogastric junction.Surg Endosc. 2007; 21: 2272-2276Crossref PubMed Scopus (49) Google Scholar, 20Shim J.H. Lee H.H. Yoo H.M. et al.Intragastric approach for submucosal tumors located near the Z-line: a hybrid laparoscopic and endoscopic technique.J Surg Oncol. 2011; 104: 312-315Crossref PubMed Scopus (33) Google Scholar Nevertheless, a surgical approach is more invasive than a solely endoscopic approach. To complete endoscopic treatment for SMT at the GEJ, these authors have used a dual-scope approach. Countertraction was provided by the second small-caliber endoscope by a snare capturing the endoloop placed over the tumor. Four cases with this technique were reported, and all large tumors (2-6 cm; median 3.25 cm) were removed successfully, with procedure times of 190 to 390 minutes. There was one case of perforation, which needed laparoscopic surgical closure but had a good clinical outcome. The procedure time was significantly longer than in other large case series, which suggests that there may be a significant learning curve for the ESD procedure for SMT at the GEJ and that it would be increasingly difficult as tumors become larger.21Li Q.L. Yao L.Q. Zhou P.H. et al.Submucosal tumors of the esophagogastric junction originating from the muscularis propria layer: a large study of endoscopic submucosal dissection (with video).Gastrointest Endosc. 2012; 75: 1153-1158Abstract Full Text Full Text PDF PubMed Scopus (92) Google Scholar Both reports state that there was no significant interendoscope interference despite the side-by-side endoscopic position. How can we best achieve countertraction? The traditional double-channel endoscope does not operate as 2 hands because both instruments passed through the accessory channels move along with the tip of the endoscope, and the double-channel endoscope does not allow adequate freedom to provide stable countertraction. To address this issue, a prototype endoscope (“R-scope”) was invented and tested.22Yonezawa J. Kaise M. Sumiyama K. et al.A novel double-channel therapeutic endoscope (“R-scope”) facilitates endoscopic submucosal dissection of superficial gastric neoplasms.Endoscopy. 2006; 38: 1011-1015Crossref PubMed Scopus (74) Google Scholar, 23Neuhaus H. Costamagna G. Deviere J. et al.Endoscopic submucosal dissection (ESD) of early neoplastic gastric lesions using a new double-channel endoscope (the “R-scope”).Endoscopy. 2006; 38: 1016-1023Crossref PubMed Scopus (119) Google Scholar, 24Lee S.H. Gromski M.A. Derevianko A. et al.Efficacy of a prototype endoscope with two deflecting working channels for endoscopic submucosal dissection: a prospective, comparative, ex vivo study.Gastrointest Endosc. 2010; 72: 155-160Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar This R-scope had 2 independent movable channels directing perpendicular directions, one of which was to provide countertraction. Even though the concept was good, this endoscope required a significant learning period to enable proficiency in its use. Additionally, it was difficult to use at a retroflexed position; thus, it was difficult to use for certain locations. Later, to mimic a surgical approach with 2 hands, a new multitasking platform was developed and compared with the double-channel endoscope for endoscopic full-thickness resection in an ex vivo animal model.25Ikeda K. Sumiyama K. Tajiri H. et al.Evaluation of a new multitasking platform for endoscopic full-thickness resection.Gastrointest Endosc. 2011; 73: 117-122Abstract Full Text Full Text PDF PubMed Scopus (37) Google Scholar This completely different and innovative platform performed well within a large gastric lumen. However, it needs further refinement with additional features and dedicated accessory devices to be clinically useful. Robotic-enhanced endosurgical system had been tested in ex vivo models as well as in live pigs. Its feasibility was proven for gastric ESD and its human trial is in progress. A recently developed endoscopic suturing device was used to create traction by a “pulley technique” to facilitate tissue removal of gastric mucosa by the ESD technique in an animal model.26Ho K.Y. Phee S.J. Shabbir A. et al.Endoscopic submucosal dissection of gastric lesions by using a Master and Slave Transluminal Endoscopic Robot (MASTER).Gastrointest Endosc. 2010; 72: 593-599Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar Reports of a new endoscopic approach to the resection of SMT without countertraction have also been published.27Wang Z. Phee S.J. Lomanto D. et al.Endoscopic submucosal dissection of gastric lesions by using a master and slave transluminal endoscopic robot: an animal survival study.Endoscopy. 2012; 44: 690-694Crossref PubMed Scopus (50) Google Scholar, 28Rieder E. Makris K.I. Martinec D.V. et al.The suture-pulley method for endolumenal triangulation in endoscopic submucosal dissection.Endoscopy. 2011; 43 (UCTN:E319–E320)PubMed Google Scholar, 29Inoue H. Ikeda H. Hosoya T. et al.Submucosal endoscopic tumor resection for subepithelial tumors in the esophagus and cardia.Endoscopy. 2012; 44: 225-230Crossref PubMed Scopus (181) Google Scholar, 30Lee C.K. Lee S.H. Chung I.K. et al.Endoscopic full-thickness resection of a gastric subepithelial tumor by using the submucosal tunnel technique with the patient under conscious sedation (with video).Gastrointest Endosc. 2012; 75: 457-459Abstract Full Text Full Text PDF PubMed Scopus (20) Google Scholar, 31Gong W. Xiong Y. Zhi F. et al.Preliminary experience of endoscopic submucosal tunnel dissection for upper gastrointestinal submucosal tumors.Endoscopy. 2012; 44: 231-235Crossref PubMed Scopus (92) Google Scholar Submucosal tunneling is first used to access the tumor, and the tumor is removed “under the mucosa” within the intestinal wall. This approach to the resection of SMT needs further study comparing it with conventional ESD or countertraction-assisted ESD to validate its concept, benefit, and feasibility for larger tumors or those at various locations. We are in an exciting era when new and innovative ideas for techniques and endoscopic equipment are developed to treat tumors in the GI tract. An additional “hand” would immensely facilitate the endoscopic resection procedure while reducing technical difficulty, and would certainly be helpful for physicians who are starting to learn the ESD procedure. Double-endoscope endoscopic submucosal dissection for the treatment of early gastric cancer accompanied by an ulcer scar (with video)Gastrointestinal EndoscopyVol. 78Issue 2PreviewEndoscopic submucosal dissection (ESD) for early gastric cancer accompanied by an ulcer scar remains challenging. Several counter-traction techniques have been attempted to facilitate ESD, but a standard procedure remains to be established. 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