CLINICAL ADVANTAGES OF ENDOSCOPIC SUBMUCOSAL DISSECTION FOR GASTRIC CANCERS IN REMNANT STOMACH SURPASS CONVENTIONAL ENDOSCOPIC MUCOSAL RESECTION

Aim: Endoscopic submucosal dissection was developed to address the shortcomings of conventional endoscopic mucosal resection. The present study evaluated the benefits of endoscopic submucosal dissection compared with conventional endoscopic mucosal resection for the treatment of neoplasms arising from the remnant stomach after gastrectomy or esophagectomy. Methods: This study, which was designed as a historical control study, evaluated 22 gastric cancers in remnant cancers treated by conventional endoscopic mucosal resection and another 40 cancers treated by endoscopic submucosal dissection. Results: Patient characteristic between the two groups were not different except for tumor size, which was larger in patients with endoscopic submucosal dissection. The local complete resection rate and the curative resection rate were significantly higher in the endoscopic submucosal dissection group compared to those in the mucosal resection group (95.0% vs 40.9% and 80.0% vs 40.9%, respectively). Complication rate showed no significant difference in the two groups, although submucosal dissection required a longer operation time. Conclusion: Endoscopic submucosal dissection represents a reliable treatment for gastric cancers in the remnant stomach, surpassing endoscopic mucosal resection.     

MANAGEMENT TO PREVENT BLEEDING DURING ENDOSCOPIC SUBMUCOSAL DISSECTION USING THE FLUSH KNIFE FOR GASTRIC TUMORS

The gastric vasculature responsible for intraoperative bleeding in endosocpic submucosal dissection (ESD) is the ramified vascular network occupying the middle of the submucosal layer and large vessels penetrating the muscle layer. Appropriate management for these vessels must be addressed. The trimming of the ramified vascular network can be safely performed with coagulation mode following shallow mucosal cutting. A large penetrating vessel usually requires precoagulation prior to dissection. These procedures are effectively performed with the water jet short needle knife (Flush knife).     

NEW DEVICE TO PERFORM COAGULATION AND IRRIGATION SIMULTANEOUSLY DURING ENDOSCOPIC SUBMUCOSAL DISSECTION USING AN INSULATION‐TIPPED ELECTROSURGICAL KNIFE

Background: Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously. Methods: Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole. Results: Our new hood was useful for hemorrhage during ESD using IT knife. Conclusions: With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy.     

Endoscopic submucosal dissection for gastric neoplasia: experience with the flex-knife

Although the standard treatment for gastric neoplasia is still surgical resection, endoscopic resection has been accepted for some of these lesions in an early stage. Among several methods of endoscopic resection, endoscopic submucosal dissection has been developed to remove the lesions in an en bloc fashion regardless of size, shape, coexisting ulcer, and location. However, indication of endoscopic submucosal dissection is strictly confined by two aspects; those are the possibility of nodal metastases and technical difficulty. Nowadays, several knives for endoscopic submucosal dissection are available and each of them has some merits and demerits. We describe how to perform endoscopic submucosal dissection in the stomach by using the flex-knife, a new endoscopic device specifically designed for submucosal dissection, emphasizing its special features from our experience.     

Advantages of endoscopic submucosal dissection over conventional endoscopic mucosal resection

BACKGROUND: Endoscopic mucosal resection is an established method for treating intramucosal gastric neoplasms. Conventional endoscopic mucosal resection has predominantly been performed using strip biopsy, but local recurrence sometimes occurs due to such piecemeal resection. Endoscopic submucosal dissection has recently been performed in Japan using new devices such as an insulation-tip diathermic knife. The efficacy and problems associated with endoscopic submucosal dissection were evaluated by comparison with conventional endoscopic mucosal resection. METHODS: Treatment consisted of conventional endoscopic mucosal resection for 48 lesions from January 1999 to October 2002, and endoscopic submucosal dissection for 59 lesions from November 2002 to June 2005. Endoscopic submucosal dissection was performed using an insulation-tip diathermic knife and flex and hook knives, as appropriate. RESULTS: For lesions >or=11 mm in size, en bloc resection rates were significantly higher with endoscopic submucosal dissection than with conventional endoscopic mucosal resection, but treatment time was significantly longer. En bloc resection rates were higher with endoscopic submucosal dissection than with conventional endoscopic mucosal resection in all areas. Treatment of lesions in the upper one-third of the stomach took a long time using endoscopic submucosal dissection, and intraoperative bleeding was frequent. However, en bloc resection rates and intraoperative bleeding with endoscopic submucosal dissection were improved using various knives. CONCLUSIONS: Endoscopic submucosal dissection can take a long time, but is superior to conventional endoscopic mucosal resection for treating intramucosal gastric neoplasms.     

Application of blunt dissection in ESD of a gastric submucosal tumor

We performed endoscopic submucosal dissection of a gastric fundus tumor.It was difficult to strip the tumor completely due to space limitation,and we used blunt dissection to remove the tumor quickly and safely.Firstly,the basal area of the 2.5 cm submucosal tumor located in the gastric fundus was cut open,and the mucosa was dissected.The tumor was difficult to peel,therefore,a snare was used and the tumor was pulled and tightened slightly.Short electronic coagulation was used during the procedure.The tumor was then bluntly dissected.This method ensured rapid and complete removal of the tumor.     

Endoscopic submucosal tunnel dissection salvage technique for ulcerative early gastric cancer

Endoscopic submucosal dissection is an effective treatment modality for early gastric cancer (EGC), though the submucosal fibrosis found in ulcerative EGC is an obstacle for successful treatment. This report presents two cases of ulcerative EGC in two males, 73- and 80-year-old, with severe fibrosis. As endoscopic ultrasonography suggested that the EGCs had invaded the submucosal layer, the endoscopic submucosal tunnel dissection salvage technique was utilized for complete resection of the lesions. Although surgical gastrectomy was originally scheduled, the two patients had severe coronary heart disease, and surgeries were refused because of the risks associated with their heart conditions. The endoscopic submucosal tunnel dissection salvage technique procedures described in these cases were performed under conscious sedation, and were completed within 30 min. The complete en bloc resection of EGC using endoscopic submucosal tunnel dissection salvage technique was possible with a free resection margin, and no other complications were noted during the procedure. This is the first known report concerning the use of the endoscopic submucosal tunnel dissection salvage technique salvage technique for treatment of ulcerative EGC. We demonstrate that endoscopic submucosal tunnel dissection salvage technique it is a feasible method showing several advantages over endoscopic submucosal dissection for cases of EGC with fibrosis.     

Resection of early esophageal neoplasms: The pendulum swings from surgical to endoscopic management

Esophageal cancer is a highly lethal disease and is the sixth leading cause of cancer related mortality in the world. The standard treatment is esophagectomy which is associated with significant morbidity and mortality. This led to development of minimally invasive, organ sparing endoscopic therapies which have comparable outcomes to esophagectomy in early cancer. These include endoscopic mucosal resection and endoscopic submucosal dissection. In early squamous cell cancer, endoscopic submucosal dissection is preferred as it is associated with cause specific 5-year survival rates of 100% for M1 and M2 tumors and 85% for M3 and SM1 tumors and low recurrence rates. In early adenocarcinoma, endoscopic resection of visible abnormalities is followed by ablation of the remaining flat Barrett's mucosa to prevent recurrences.Radiofrequency ablation is the most widely used ablation modality with others being cryotherapy and argon plasma coagulation. Focal endoscopic mucosal resection followed by radiofrequency ablation leads to eradication of neoplasia in93.4% of patients and eradication of intestinal metaplasia in 73.1% of patients.Innovative techniques such as submucosal tunneling with endoscopic resection are developed for management of submucosal tumors of the esophagus. This review includes a discussion of various endoscopic techniques and their clinical outcomes in early squamous cell cancer, adenocarcinoma and submucosal tumors. An overview of comparison between esophagectomy and endoscopic therapy are also presented.     

RISK MANAGEMENT IN ENDOSCOPIC SUBMUCOSAL DISSECTION USING NEEDLE KNIFE IN KOREA

The needle knife is used for mucosal incision during endoscopic mucosal resection (EMR). The first author has used the needle knife for EMR since 1996 to overcome several limitations. Conventional EMR is not able to be used to remove tumors >15 mm. Excessive burning effect on the margin during strip biopsy leads to misdiagnosis during evaluation of resection margins. Relatively larger specimens could be resected and resection margins evaluated effectively with EMR with needle knife. Nowadays the needle knife is used to perform endoscopic submucosal dissection (ESD) from mucosal incision to submucosal dissection. The advantages of needle knife are as follows: (i) the lumen of the stomach can be kept clear during the whole procedure because of less burning effect; (ii) the procedure time for ESD is short because the needle knife has a very thin body, enabling the mucosal and submucosal layer to be cut quickly; and (iii) the needle knife can provide cutting action with the tip. In contrast, the needle knife has a high potential to cause perforation during incision and dissection. Only experts can use the needle knife safely. The perforated site can be closed endoscopically using hemoclips. To prevent perforation the needle knife should be kept parallel to the gastric wall during dissection. In conclusion, the needle knife has many advantages as well as a higher risk of perforation. However, the success rate for ESD using the needle knife increases with sufficient experience.     

口袋式内镜黏膜下剥离术在消化道早期肿瘤治疗中的应用

内镜黏膜下剥离术是胃肠道早期肿瘤的有效治疗方法，但在部分病例中，由于病变大小、部位等原因，无法取得预期疗效。口袋式内镜黏膜下剥离术是在内镜黏膜下剥离术的基础上发展而来的一项新兴内镜技术，具有手术时间短、病灶整块切除率高、并发症发生率低等优点，逐渐应用于消化道早期肿瘤的治疗中。     

Esophageal Mucosal Autograft for Preventing Stricture After Widespread Endoscopic Submucosal Dissection of Superficial Esophageal Lesions

Background: Although esophageal mucosal autograft prevents esophageal stricture after widespread endoscopic submucosal dissection and has been reported as a new technique, it is relatively unproven in clinical practice. This prospective study was conducted to evaluate our experience using esophageal mucosal autograft to prevent strictures after widespread endoscopic submucosal dissection in patients with widespread superficial esophageal lesions.Methods: Between October 2017 and June 2018, 15 patients with widespread superficial esophageal lesions were consecutively treated with widespread endoscopic submucosal dissection and then underwent esophageal mucosal autograft. The main outcomes measured included esophageal epithelialization and esophageal stricture.Results: The median longitudinal diameter of the widespread superficial esophageal lesions was 5.2 cm. All 15 patients were successfully treated with widespread endoscopic submucosal dissection and esophageal mucosal autograft, and the median procedural time was 182 minutes. During follow-up (median, 23 months), esophageal epithelialization was found in 13 patients (86.7%), and 7 patients experienced esophageal stricture (46.7%). In those 7 patients, the esophageal strictures were successfully relieved after endoscopic balloon dilation or endoscopic radial incision. No complications related to endoscopic balloon dilation/endoscopic radial incision occurred. Additionally, local recurrence was found in 1 patient with poorly differentiated squamous cell carcinoma, and further surgical resection was performed.Conclusions: Esophageal mucosal autograft appears to be an efficient approach to reconstructing local esophageal epithelium and might have a potential role in preventing esophageal stricture after widespread endoscopic submucosal dissection. However, as a new technique, it needs more improvement to enhance its role in preventing esophageal stricture after widespread endoscopic submucosal dissection.     

Acute Intestinal Obstruction after Endoscopic Submucosal Dissection: Report of a Case

The endoscopic submucosal dissection is a novel noninvasive therapeutic procedure for the early stage colorectal neoplasm. Endoscopic submucosal dissection has an advantage over endoscopic mucosal resection by en bloc resection of the mucosal lesion regardless of the size. As endoscopic submucosal dissection becomes popular, the rate of complication is expected to increase. Although uncommon, complications of endoscopic submucosal dissection have been reported including hemorrhage and perforation. Acute colon obstruction is a very rare complication of endoscopic submucosal dissection, but can be potentially lethal if the diagnosis is delayed. We report a case of acute intestinal obstruction after ESD of early colon cancer located in the cecal base.     

Endoscopic submucosal dissection as a staging measure may not lead to worse prognosis in early gastric cancer patients with additional gastrectomy

BACKGROUND: Endoscopic submucosal dissection is a novel endoluminal technique that enables resection of early stage gastrointestinal malignancies in an en bloc fashion. AIM: To assess whether preceding endoscopic submucosal dissection affected the prognoses of patients who underwent additional gastrectomy with lymph node dissection due to suspicion of nodal metastasis from endoscopic submucosal dissection specimens. PATIENTS AND METHODS: Thirty-one patients with early gastric cancer who underwent gastrectomy after endoscopic submucosal dissection were retrospectively investigated in terms of their survival and tumour recurrence. Additional gastrectomy was performed when histology of the endoscopic submucosal dissection specimens revealed that the tumours did not meet the criteria for node-negative cancers. RESULTS: Twenty-three (74%) and eight (26%) patients had undergone endoscopic submucosal dissection previously due to clinical diagnoses of node-negative cancers and possible node-positive cancers, respectively. Histology of the resected stomachs and lymph nodes revealed residual carcinoma of the stomach in two (6.5%) patients and nodal metastases in four (13%) patients. All patients remain alive without recurrence (median follow-up, 3.4 years; range, 0.6-5.2 years). CONCLUSIONS: Based on the histology of endoscopic submucosal dissection specimens, preceding endoscopic submucosal dissection itself had no negative influence on a patient's prognosis when additional gastrectomy was performed. It may be permissible to resect some early gastric cancers by endoscopic submucosal dissection as a first step to prevent unnecessary gastrectomy, if technically resectable.     

Endoscopic options for treatment of dysplasia in Barrett's esophagus

Recent advances in the endoscopic treatment of dysplasia in Barrett's esophagus(BE) have allowed endoscopists to provide effective and durable eradication therapies. This review summarizes the available endoscopic eradication techniques for dysplasia in patients with BE including endoscopic mucosal resection, endoscopic submucosal dissection, photodynamic therapy, argon plasma coagulation, radiofrequency ablation and cryotherapy.     

25例消化道病变ESD治疗体会

目的探讨内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)处理消化道病灶的实用性及安全性。方法对7例消化道早期癌肿及18例深度未超过黏膜下层的黏膜下肿瘤共25例行ESD治疗。结果 25例患者均一次性完整切除病灶。所有治疗中均伴有术中出血,用ESD专用热止血钳、APC、金属止血夹成功止血,未发生术后迟发出血。术中穿孔1例,穿孔率为4%(1/25),以金属夹成功夹闭,无术后迟发穿孔。术后随访20例(包括7例消化道早期癌肿及13例黏膜下肿瘤),随访期为7～17个月(平均12.2个月),随访创面均完全愈合,未见复发病灶。结论ESD作为一种微创治疗方法,对于浸润深度不超过黏膜下层的病灶可以一次性大块剥离,从而获得完整的病理学诊断资料,安全性较好。但操作过程复杂,技术难度高。     

Endoscopic submucosal dissection of stomach neoplasms after unsuccessful endoscopic resection

BACKGROUND: Endoscopic submucosal dissection is a novel endoluminal endoscopic surgery that enables resection of pre-malignant and early-stage malignant gastrointestinal neoplasms in an en bloc fashion. AIM: To assess the feasibility of endoscopic submucosal dissection of stomach neoplasms with submucosal fibrosis caused by unsuccessful endoscopic resection. PATIENTS AND METHODS: Stomach endoscopic submucosal dissection was performed in ten consecutive patients who had unsuccessful endoscopic tumour resection at another hospital between 2003 and 2006. Seven patients had recurrent tumours after complete endoscopic resection, and three patients had incomplete resections due to complications or technical difficulties. Technical feasibility and follow-up data were collected from the patients' reports. RESULTS: All tumours were resected by endoscopic submucosal dissection in one piece without complications. R0 resection (en bloc resection with tumour-free margins) was achieved in nine patients (90%). One patient received additional surgery (gastrectomy) because of submucosal deep invasion with vascular infiltration of the cancer. All patients, including the patient with gastrectomy, have survived without recurrence during a mean follow-up period of 21.4 months (range 3-36 months). CONCLUSIONS: Endoscopic submucosal dissection is an effective and safe method for resection of stomach neoplasms after unsuccessful endoscopic resection.     

Randomized controlled trial comparing submucosal endoscopy with mucosal resection and endoscopic submucosal dissection in the esophagus and stomach: Animal study

Background and Aim

In Western countries, endoscopic submucosal dissection (ESD) has not prevailed as a result of training problems and a target patient population. We have previously reported a hybrid ESD technique, submucosal endoscopy with mucosal resection (SEMR), in which the submucosal dissection is carried out chiefly by blunt balloon dissection. We have also reported successful application in the porcine colon. In the present study, we compared the safety and efficacy of SEMR with ESD in the porcine esophagus and stomach.

Methods

SEMR and ESD were carried out in eight domestic pigs under general anesthesia. Resection sites were marked by circumferential coagulation. After circumferential ESD knife mucosal incision, submucosal fluid cushion (SFC) was created. In the SEMR group, the balloon catheter was inserted deep into the SFC. The balloon was then inflated and pulled back toward the endoscope tip repeatedly, altering the direction, to disrupt the submucosa. Residual strands were cut with an IT‐knife. En bloc resection rates, procedure times, complications and dissection difficulty scales (DDS) were recorded prospectively. DDS were rated using a visual analog scale.

Results

Thirty‐two resections (8 SEMR/8 ESD in the esophagus; 8 SEMR/8 ESD in the stomach) were done with no major adverse events. There was no statistical difference between the two techniques in either location in the above categories measured.

Conclusions

SEMR and traditional ESD are comparable techniques in safety and effectiveness when carried out in the esophagus and stomach. SEMR may serve as a more appealing technical option for endoscopists who are unable to sustain a traditional ESD practice volume.     

HEMOSTASIS WITH HOOK KNIFE DURING ENDOSCOPIC SUBMUCOSAL DISSECTION

Major complications reported with endoscopic submucosal dissection are bleeding and perforation. The most important step in preventing such complications is to maintain visualization of the submucosal layer. The hook knife is not only a useful cutting device for submucosal dissection, but the device also provides effective means for hemostasis and prevention of bleeding during endoscopic submucosal dissection. Vessels with a diameter of 1 mm or less do not bleed if cut with a hook knife using spray mode coagulation.     

Technique of the double-channel ESD method performed with an EEMR tube

Endoscopic submucosal dissection (ESD) recently has been aggressively performed to treat superficial esophageal cancer; however, it is difficult to secure a good field of view for mucosal dissection, and the technique requires considerable skill. We have developed a double-channel ESD method using an endoscopic esophageal mucosal resection (EEMR) tube that makes it possible to perform the submucosal dissection with a good field of view while applying countertraction. Countertraction is achieved by maneuvering a fine grasping forceps inserted through the side channel of the EEMR tube, and the field of view of the submucosal dissection layer can be easily exposed. This technique can be performed while constantly observing the submucosal dissection layer with a stable field of view, and it is also easy to handle the blood vessels. Moreover, there is no disturbance of the field of view by the dissected mucosa.     

Endoscopic submucosal dissection in dogs in a World Gastroenterology Organisation training center

AIM: To evaluate if canine models are appropriate for teaching endoscopy fellows the techniques of endoscopic submucosal dissection (ESD). METHODS: ESD was performed in 10 canine models under general anesthesia, on artificial lesions of the esophagus or stomach marked with coagulation points. After ESD, each canine model was euthanized and surgical resection of the esophagus or stomach was carried out according to “The Principles of Humane Experimental Technique, Russel and Burch“. The ESD specimens were fi...