Subjects
We investigated 123 lesions in 121 consecutive patients who underwent gastric ESD in the Department of Gastroenterology at Kushiro Rosai Hospital between April 2018 and January 2020. Surgeons of gastric ESD were an endoscopist (S.A.) and some trainees with experience of less than 30 ESD procedures in humans. All of the procedures were tutored by one endoscopist (S.A.). Up until March 2018, ESD was performed in 169 patients (in the pharynx in 1 patient, esophagus in 16 patients, stomach in 128 patients and large intestine in 24 patients) under the guidance of tutors at other institutions. Perforation and delayed perforation did not occur in any cases, and DB occurred in 4 cases (3.1%, ESD of the stomach). From April 2018, the endoscopist (S.A.) was only a tutor at our institution. Patients at a high risk for DB were defined as patients being administered direct oral anticoagulants (DOAC) or warfarin, patients on dialysis and patients who had received heparin replacement. Other patients were defined as patients at a low risk for DB. We evaluated en bloc R0 resection, curative resection, length of the tumor, length of the resected specimen, resection area, resection time, resection speed, method for preventing DB, number of clips used for the MSCC method, time and speed of the PEC, MSCC and PMSCC methods with or without the use of second-look endoscopy and vonoprazan, procedures at the second-look or follow-up endoscopy, and procedural and delayed procedural adverse events including perforation during ESD, delayed perforation, DB and post-ESD stenosis. En bloc R0 resection was defined as tumor resection in a single piece with tumor-free lateral and vertical margins. Resection time was the duration from the first injection until achieving complete resection. The resection speed was defined as the resection area divided by resection time (cm2/h). The resection area was regarded to be approximately oval in shape. The time of the PEC, MSCC and PMSCC methods was defined as the interval from insertion of the first device for the prevention of DB until completion of the method. The speed of the PEC, MSCC and PMSCC methods was defined as the resection area divided by 10 × the time of PEC, MSCC and PMSCC method (cm2/10 min). Perforation was defined as the creation of an immediately recognized hole in the gastric wall. Delayed perforation was defined as the presence of free air on abdominal computed tomography or X-ray after completion of the procedure in patients without perforation during ESD and no symptoms of peritoneal irritation after ESD. DB was defined as bleeding requiring emergency endoscopic hemostasis or transfusion or the presence of hemoglobin loss ≥ 2 g/dL following ESD [11]. Delayed procedural adverse events were assessed for 30 days post-ESD. Continuation or cessation of antithrombotic agents was determined according to the Guidelines for Gastroenterological Endoscopy in Patients Undergoing Antithrombotic Treatment [12–13]. We examined ABO blood type because it has been reported that blood type O may be less likely to clot than other types [14].
Esd Method And Management After Esd
GIF-H290Z (Olympus Optical, Tokyo, Japan) and a needle knife were used for assessing the lesion margin and marking around the lesion. ESD was performed under conscious sedation using a single-channel gastrointestinal endoscope with a transparent attachment hood fitted to the tip (GIF-Q260J; Olympus Optical). When some difficulties were observed, we used another twin-channel gastrointestinal endoscope (GIF-2TQ260M; Olympus Optical). The GIF-2TQ260M endoscope has a multi-bending and a water jet function. Hyaluronic acid solution was injected into the submucosal layer before mucosal and submucosal cutting. After injection, we mainly performed mucosal cutting with a needle knife and dissection beneath the lesion using an IT knife-2 (Olympus Optical). When some difficulties were observed, we used another knife: hook knife (Olympus Optical), flush knife (Fujifilm Optical) or clutch cutter (Fujifilm Optical). We used a VIO 200D electrosurgical generator (ERBE Elektromedizin, GmbH, Tübingen, Germany). Hemorrhage was controlled using hemostatic forceps such as Coagrasper (Olympus Optical, monopolar hot hemostasis forceps) for the upper digestive tract.
After ESD, a proton-pump inhibitor (omeprazole at 20 mg, twice a day) was intravenously injected. The patient’s doctor in the ward rarely instructed a second-look endoscopy to be performed on postoperative day (POD) 1. If there were no problems, oral food intake was started on POD 2. Then an oral proton-pump inhibitor (esomeprazole at 20 mg/day or lansoprazole at 30 mg/day or rabeprazole at 20 mg/day) or vonoprazan (20 mg/day) was administered for a minimum of eight weeks. Sodium alginate (60 ml/day) and aluminum hydroxide gel, magnesium hydroxide (160 ml/day) were administered for a minimum of three days. Before the patient was discharged from the hospital, follow-up endoscopy was performed on PODs 5–7
Method For Prevention Of Db
We previously described a new method combining the use of PGA sheets and fibrin glue with a modified SCC method for preventing DB after gastric ESD [10]. First, a coagulation procedure was performed after lesion resection, mainly in the vessels at the margin of the ulcer base. Then, perforator vessels emerging between muscle layers were actively sought and clipped using short hemoclips (HX-610-135S, Olympus). Because perforator vessels may also be present in carbonized areas of the ulcer base, clipping was also actively performed in such areas, this constituted the modification of the search, coagulation, and clipping method. For patients at low risk of DB, we ended with this procedure. For patients at high risk of DB, we moved on to the next procedure. In the next procedure, several large and small PGA sheets were placed (based on the size of the ulcer base), using methods proposed by Kobayashi et al. [15] and Takimoto et al. [16], respectively. Finally, fibrin glue was sprayed. All these steps constitute the polyglycolic acid sheets, fibrin glue, and modified search, coagulation, and clipping (PMSCC) method.
Pathological Assessment Of Resected Specimens And Ethics
All resected specimens from the stomach were cut into longitudinal slices of 2–3 mm in width and were embedded in paaraffin. Each slice was stained with hematoxylin–eosin and examined microscopically. Curative resection of adenocarcinoma was previously described by the Japanese Gastric Cancer Association. [17].
This study was conducted in accordance with the rules and regulations of the Kushiro Rosai Hospital Institutional Review Board (study registration number: 19233). Written informed consent was obtained from all study subjects. The design of this study is a retrospective case series.
Statistical analysis
All statistical analyses were performed with EZR (Saitama Medical Center, Jichi Medical University, Saitama, Japan), which is a graphical user interface for R (The R Foundation for Statistical Computing, Vienna, Austria). More precisely, EZR is a modified version of R commander designed to add statistical functions frequently used in biostatistics [18]. Continuous and non-parametric variables were expressed as medians with 25th and 75th percentile values.