PDF
Citation
Print
INTRODUCTION
The clutch cutter (CC) was designed to mitigate the risk of adverse effects associated with endoscopic submucosal dissection (ESD) when using standard knives. This device uses electrosurgical currents to grasp, pull, coagulate, and incise the target tissue.1,2 In previous studies focusing on early stage epithelial neoplasms, ESD performed with CC (ESD-CC) demonstrated a high histologic complete resection (R0 resection) rate and a low incidence rate of adverse events.3-7 However, the outcomes of treating subepithelial lesions within the esophagogastric submucosa (SELEGSM) using ESD-CC have not yet been investigated. This study aimed to evaluate the efficacy and safety of ESD-CC for the treatment of SELEGSM.
METHODS
Patients and lesions
This prospective study enrolled 15 patients with 18 SELEGSMs who underwent ESD-CC at Aso Iizuka Hospital between June 2007 and April 2020. The inclusion criterion for ESD-CC was the presence of SELEGSM which were not continuous with the muscularis propria, as diagnosed by preoperative endoscopic ultrasound (EUS).
CC short type
The short-type Clutch Cutter (model DP2618DT-35; Fujifilm) (Fig. 1) features serrated jaws that enable the endoscopist to securely grasp the targeted tissue. These jaws measure 0.4 mm in width and 3.5 mm in length, can rotate 360°, and has insulated external surfaces to minimize electrical tissue damage.2,7 The insert was 2.7 mm in diameter. CC facilitates the management of the entire ESD process. The high-frequency generator used is the VIO 300D (Erbe). For marking, the forced coagulation mode was set to 30 W with an effect level of 3. Mucosal incision and submucosal dissection were performed using the Endocut-Q mode (effect 2, duration 3, interval 1), whereas the soft coagulation mode (effect 5, 100 W) was used for preventive coagulation and hemostasis.
ESD-CC procedures
ESD-CC was performed using a single working channel procedural endoscope with a water jet system (EG-450RD5, EG-530RD5: Fujifilm; Q260J: Olympus). To ensure the adequacy of the endoscopic view and to apply tension to the submucosal tissue in the field of view during ESD-CC, a clear hood was fitted to the endoscope tip. The techniques used for ESD-CC have been detailed elsewhere.2,7 The ESD-CC method involves injection of a solution containing 10% glycerin, 0.9% NaCl, and 5% fructose (Glyceol; Chugai Pharmaceutical Co.) or hyaluronic acid (MucoUp; Boston) combined with a small volume of epinephrine and indigo carmine dye into the submucosal layer. Mucosal incision and submucosal dissection were performed to excise the lesion completely using the CC. Bleeding veins or arteries were secured, maneuvered, and coagulated with the CC using an electrosurgical current to halt the bleeding. All incisions and coagulation procedures were performed after the target area was secured and moved away from the proper muscle layer. The lesion was completely resected.
Histopathological evaluation
The excised specimens were sectioned at 2-mm intervals perpendicular to the surface. Tumor diameter, depth of infiltration, histological type, vascular and lymphatic involvement, and presence of tumors at the vertical and horizontal margins were assessed.
Evaluation of ESD-CC efficacy and adverse effects
The operating time was measured from initial injection into the submucosa to completion of submucosal dissection. If the lesion was removed in a single piece and the resection margin was visibly tumor-negative, the resection was considered en bloc. Resection was deemed tumor-negative (R0) if the vertical and lateral sections showed no microscopic evidence of tumor cells, irrespective of the histological characteristics.
Perforation during ESD-CC was identified endoscopically, whereas perforation after ESD-CC was judged based on abdominal pain and/or the detection of free air through plain radiography and/or computed tomography following ESD-CC. Bleeding after ESD-CC was defined as the clinical evidence of bleeding that necessitated endoscopic hemostasis.7
RESULTS
The clinicopathological characteristics are detailed in Table 1. Table 2 summarizes the technical outcomes. The technique of grasping and pulling or lifting the target tissue before excision facilitated precise cutting of the target area and enabled application of adequate pre-cut coagulation (Supplementary Video 1). The en bloc resection rate was 94.4% (esophagus, 100%; stomach, 91.7%) and the R0 resection rate was 88.9% (esophagus, 100%; stomach, 83.3%). Figure 2 shows a representative example of ESD-CC applied to an esophageal granular cell tumor. In cases where R0 resection was unattainable, ESD-CC was discontinued in one instance (case no. 12) (Fig. 3) because of tumor invasion into the muscularis propria, which was identified during ESD (the postsurgical resection diagnosis was a granular cell tumor infiltrating the muscularis propria). In another case (case no. 14), the vertical margin could not be evaluated because of thermal degeneration. The median operation duration was 39 min (esophagus, 27.5; stomach, 45). No complications were observed. The final diagnoses for esophageal lesions were granular cell tumors in five cases (83.3%) and leiomyoma in one case (16.7%). Gastric lesions were diagnosed as neuroendocrine tumors in six cases (50.0%), ectopic pancreas in two cases (16.7%), granular cell tumor in one case (8.3%), inflammatory fibroid polyp in one case (8.3%), lipoma in one case (8.3%), and leiomyosarcoma in one case (8.3%).
DISCUSSION
SELEGSM encompasses a broad spectrum of diseases ranging from benign to malignant conditions.8,9 Despite this diversity, a significant proportion of these tumors penetrate deeply into the submucosa,10 necessitating the use of specialized techniques to achieve curative resection with clear vertical margins.11-15 Conventional endoscopic polypectomy and endoscopic mucosal resection (EMR) for SELEGSM have a high rate of positive vertical margins (0%–16.7%); therefore, several modified EMRs (band ligation-assisted, cap-assisted, and underwater) have been developed, which have lowered the rates of positive vertical margins (0%–3.7%) in retrospective case series.14-16 These methods are effective, simple, safe, and low-cost, but are limited to small lesions and theoretically do not allow direct endoscopic visual control of the resection depth. Kim et al.16 reported that ESD (2.6%) had a significantly lower rate of positive vertical margins than did EMR (16.7%) in the endoscopic resection of gastric neuroendocrine tumors. In this context, ESD is preferred over conventional EMR as it involves precise submucosal dissection immediately above the proper muscle layer under endoscopic visualization, coupled with accurate histologic evaluation of the resected specimen.17-20 However, technical literature on the use of a conventional knife for ESD in SELEGSM is limited.12,13,18,19,21 Furthermore, data on ESD-CC are lacking. To our knowledge, this is the first prospective study to investigate the technical efficacy of ESD-CC in SELEGSM.
ESD presents technical challenges and carries a considerable risk of complications such as bleeding and perforation.22 Each stage of the procedure requires specialized instruments including special knives or hemostatic forceps.2,23 ESD-CC offers four safety advantages: (1) accurate targeting through tissue fixation, (2) reliable hemostasis via tissue compression, (3) reduced electrical tissue injury to the muscularis propria by elevating the grasped tissue, and (4) minimal external electrical damage through external insulation.2,7 This study demonstrated that intraoperative bleeding could be efficiently managed using CC alone without the need for hemostats, allowing all ESD phases to be executed exclusively with CC (1-device ESD method). Previous studies have established ESD-CC as a safe (perforation rate: 0%–3.6%, delayed bleeding rate: 0%–4.2%) and effective (en bloc resection rate: 88.9%–100%) technique for the removal of early gastrointestinal epithelial tumors using a single device.2-7 This method is straightforward and easy to learn, involving merely the repetitive actions of grasping and elevating the target tissue, followed by coagulation or incision with an electrosurgical current. Notably, the self-completion rates of ESD by novice endoscopists were significantly higher with CC than with conventional knives (61.7% vs. 24.5%; p<0.001).5
Table 3 shows a comparison of the SELEGSM ESD outcomes between conventional knives12,13,18,19 and CC (this study). The en bloc and R0 resection rates for ESD using conventional knives were 88.2% to 100% and 73.3% to 100%, respectively. In contrast, the en bloc and R0 resection rates for ESD with CC were 94.4% and 88.9%, respectively. The en bloc and R0 resection rates were comparable between the ESD-conventional knives knives and ESD-CC methods. Perforation, a significant adverse event of ESD for SELEGSM, has a reported frequency of 0% to 11.7%.12,13,18,19 In this study, the perforation rate of ESD-CC was 0%. Delayed bleeding, another major adverse effect of ESD, has a reported frequency of 0% to 13.3%. Meanwhile, the frequency of delayed bleeding in patients who underwent ESD-CC was 0%, and the frequencies of perforation and delayed bleeding were comparable between the ESD-conventional and ESD-CC methods. The precise and effective hemostatic capabilities of the CC, akin to hemostatic forceps,2 are crucial for preventing perforation and delayed bleeding post-ESD. This and previous studies2-7 highlight the ability of CC to perform effective pre-cut coagulation, while ensuring immediate cessation of unintentional bleeding without the need to switch hemostatic forceps. This method, therefore, significantly reduces the risk of ESD-related adverse events. However, to date, studies on the technical outcomes of ESD for SELEGSM have reported only a small number of cases from advanced ESD centers.12,13,18,19 Further case studies are required to validate these findings.
The present study had a specific limitation: it involved a small sample size of 15 patients from a single center. To thoroughly assess the effectiveness of our method, further large controlled randomized trials comparing CC with an insulation-tipped knife, needle-type knife, or other devices should be conducted.
In conclusion, our preliminary outcomes suggest that ESD-CC is a viable choice for endoscopic treatment of SELEGSMs. This method requires only a single resection device (CC) and is effective, safe, and technically straightforward.
XML Download