Makoto Oryu

Efficacy and safety of over-the-scope clip: Including complications after endoscopic submucosal dissection

AIM To retrospectively review the results of over-the-scope clip (OTSC) use in our hospital and to examine the feasibility of using the OTSC to treat perforations after endoscopic submucosal dissection (ESD). METHODS We enrolled 23 patients who presented with gastrointestinal (GI) bleeding, fistulae and perforations and were treated with OTSCs (Ovesco Endoscopy GmbH, Tuebingen, Germany) between November 2011 and September 2012. Maximum lesion size was defined as lesion diameter. The number of OTSCs to be used per patient was not decided until the lesion was completely closed. We used a twin grasper (Ovesco Endoscopy GmbH, Tuebingen, Germany) as a grasping device for all the patients. A 9 mm OTSC was chosen for use in the esophagus and colon, and a 10 mm device was used for the stomach, duodenum and rectum. The overall success rate and complications were evaluated, with a particular emphasis on patients who had undergone ESD due to adenocarcinoma. In technical successful cases we included not only complete closing by using OTSCs, but also partial closing where complete closure with OTSCs is almost difficult. In overall clinical successful cases we included only complete closing by using only OTSCs perfectly. All the OTSCs were placed by 2 experienced endoscopists. The sites closed after ESD included not only the perforation site but also all defective ulcers sites. RESULTS A total of 23 patients [mean age 77 years (range 64-98 years)] underwent OTSC placement during the study period. The indications for OTSC placement were GI bleeding (n = 9), perforation (n = 10), fistula (n = 4) and the prevention of post-ESD duodenal artificial ulcer perforation (n = 1). One patient had a perforation caused by a glycerin enema, after which a fistula formed. Lesion closure using the OTSC alone was successful in 19 out of 23 patients, and overall success rate was 82.6%. A large lesion size (greater than 20 mm) and a delayed diagnosis (more than 1 wk) were the major contributing factors for the overall unsuccessful clinical cases. The location of the unsuccessful lesion was in the stomach. The median operation time in the successful cases was 18 min, and the average observation time was 67 d. During the observation period, none of the patients experienced any complications associated with OTSC placement. In addition, we successfully used the OTSC to close the perforation site after ESD in 6 patients. This was a single-center, retrospective study with a small sample size. CONCLUSION The OTSC is effective for treating GI bleeding, fistulae as well as perforations, and the OTSC technique proofed effective treatment for perforation after ESD.

Metabolic syndrome, obesity, and gastrointestinal cancer.

Metabolic syndrome is a cluster of metabolic abnormalities and is defined as the presence of three or more of the following factors: increased waist circumference, elevated triglycerides, low high-density lipoprotein cholesterol, high blood pressure, and high fasting glucose. Obesity, which is accompanied by metabolic dysregulation often manifested in the metabolic syndrome, is an established risk factor for many cancers. Adipose tissue, particularly visceral fat, is an important metabolic tissue as it secretes systemic factors that alter the immunologic, metabolic, and endocrine milieu and also promotes insulin resistance. Within the growth-promoting, proinflammatory environment of the obese state, cross-talk between macrophages, adipocytes, and epithelial cells occurs via obesity-associated hormones, adipocytokines, and other mediators that may enhance cancer risk and progression. This paper synthesizes the evidence on key molecular mechanisms underlying the obesity-cancer link.

Outcomes of gastrointestinal defect closure with an over-the-scope clip system in a multicenter experience: An analysis of a successful suction method

AIM To demonstrate the clinical outcomes of a multicenter experience and to suggest guidelines for choosing a suction method. METHODS This retrospective study at 5 medical centers involved 58 consecutive patients undergoing over-the-scope clips (OTSCs) placement. The overall rates of technical success (TSR), clinical success (CSR), complications, and procedure time were analyzed as major outcomes. Subsequently, 56 patients, excluding two cases that used the Anchor device, were divided into two groups: 14 cases of simple suction (SS-group) and 42 cases using the Twin Grasper (TG-group). Secondary evaluation was performed to clarify the predictors of OTSC success. RESULTS The TSR, CSR, complication rate, and median procedure time were 89.7%, 84.5%, 1.8%, and 8 (range 1-36) min, respectively, demonstrating good outcomes. However, significant differences were observed between the two groups in terms of the mean procedure time (5.9 min vs 14.1 min). The CSR of the SS- and TG-groups among cases with a maximum defect size ≤ 10 mm and immediate or acute refractory bleeding was 100%, which suggests that SS is a better method than TG in terms of time efficacy. The CSR in the SS-group (78.6%), despite the technical success of the SS method (TSR, 100%), tended to decrease due to delayed leakage compared to that in the TG-group (TSR, CSR; 88.1%), indicating that TG may be desirable for leaks and fistulae with defects of the entire layer. CONCLUSION OTSC system is a safe and effective therapeutic option for gastrointestinal defects. Individualized selection of the suction method based on particular clinical conditions may contribute to the improvement of OTSC success.

Effects of Gastric Irrigation on Bacterial Counts before Endoscopic Submucosal Dissection: A Randomized Case Control Prospective Study

Objective The antiseptic effect of gastric irrigation before endoscopic submucosal dissection (ESD) has not yet been reported. The aim of the randomized prospective study is to evaluate the antiseptic effects of gastric irrigation of saline solution before ESD by evaluating bacterial count. Methods This prospective randomized controlled trial included 50 patients diagnosed with early gastric cancer who were randomly divided into 2 groups (25 patients in each group) by using the opaque envelope method: the clean group (irrigation with 2 L saline solution before ESD) and the regular group (no irrigation). The gastric juice was collected and cultured before ESD. The entire stomach was irrigated using a water jet attached to an endoscope. After ESD with resection and removal of the tumor specimen, a postoperative culture of the gastric juice was obtained using the same method as the preoperative culture. Results The mean log bacterial count of the post-gastric irrigation gastric juice was 5.08±0.75 in the regular group and 1.86±0.86 in the clean group. The difference in the bacterial counts was significant between the groups (P = 0.0004). The difference in the white blood cells (WBC) count on POD 1 was significant (P = 0.044). WBC count on POD 2 did not significantly differ between the groups (P = 0.3). The difference in the body temperature (BT) on POD 1 was significant (P = 0.017), On POD 2 the BT was not significant between the groups (P = 0.5). On POD 1, 88% of the patients in the regular group and 16% of the patients in the clean group had mild to moderate spontaneous pain (P = 0.0026). On POD 2 the proportion with mild to moderate spontaneous pain was 36% and 24% in the regular group and the clean group, respectively (P = 0.1). Conclusion Pre-ESD gastric irrigation with saline solution is effective and feasible for suppressing infection during the ESD procedure with favorable clinical outcomes. Trial registration information The university hospital medical information network (UMIN) #000008691.

Submucosal tunneling techniques: current perspectives

Advances in endoscopic submucosal dissection include a submucosal tunneling technique, involving the introduction of tunnels into the submucosa. These tunnels permit safer offset entry into the peritoneal cavity for natural orifice transluminal endoscopic surgery. Technical advantages include the visual identification of the layers of the gut, blood vessels, and subepithelial tumors. The creation of a mucosal flap that minimizes air and fluid leakage into the extraluminal cavity can enhance the safety and efficacy of surgery. This submucosal tunneling technique was adapted for esophageal myotomy, culminating in its application to patients with achalasia. This method, known as per oral endoscopic myotomy, has opened up the new discipline of submucosal endoscopic surgery. Other clinical applications of the submucosal tunneling technique include its use in the removal of gastrointestinal subepithelial tumors and endomicroscopy for the diagnosis of functional and motility disorders. This review suggests that the submucosal tunneling technique, involving a mucosal safety flap, can have potential values for future endoscopic developments.

Analysis of the amount of tissue sample necessary for mitotic count and Ki-67 index in gastrointestinal stromal tumor sampling

There are no established opinions concerning whether the amount of tissue affects the accuracy of histological analyses in gastrointestinal stromal tumors (GISTs). The aim of the present study was to investigate the appropriate amount of tissue sample needed for mitotic count based on the risk classification of GISTs and the Ki-67 index using the following three methods: endoscopic ultrasound-guided fine-needle aspiration (FNA), a novel sampling method called tunneling bloc biopsy (TBB), and biopsy forceps followed by TBB (Bf). Forty-three samples (12 FNA, 17 TBB and 14 Bf) diagnosed as GISTs by immunohistological analysis were utilized. The major and minor axes and overlay area of one piece of specimen (OPS) from the three sampling methods were measured using digital imaging software and were analyzed comparatively regarding the acquisition of histological data. The mean major and minor axes (mm) and overlay areas (mm2) were in the order of TBB > Bf > FNA. The evaluable rates by mitotic count and Ki-67 were, respectively, 75% (9/12) and 83.3% (10/12) for FNA samples, 100% (17/17) and 100% (17/17) for TBB samples, and 100% (14/14) and 100% (14/14) for Bf samples (P>0.05). Three FNA samples were judged unevaluable due to too small specimens in overall diagnosis including mitotic count and Ki-67, calculating the cut-off value for the overlay area of OPS as 0.17 mm2. Comparing the concordance rates between the pre- and post-operative samples, TBB samples was significantly better than FNA (P<0.05). Conclusively, while the amounts of tissues obtained by TBB and Bf are unnecessary for the histological assessment of mitotic count and Ki-67 index, developments of the FNA method are needed to minimize sample error. Considering the technical aspects, as well as the size of the specimens, could help to guide therapeutic planning and improve diagnostic yield for GI subepithelial tumors.

Cytomegalovirus-associated gastric ulcer: A side effect of steroid injections for pyloric stenosis

The local injection of triamcinolone acetonide (TA) is effective in preventing pyloric stenosis and deformity following large endoscopic submucosal dissection (ESD). However, because of its long-acting nature, TA can induce long-term local immunosuppression and subsequent adverse events. We report a case of a cytomegalovirus (CMV) ulcer that formed only at the TA local injection site. A 68-year-old man underwent ESD to treat early gastric cancer that formed over the pylorus. The lesion extended to the duodenum, and an artificial ulcer covered more than two-thirds of the circumference of the pylorus. To prevent pyloric stenosis, TA was locally injected into the ulcer floor. On day 12, a deeper ulcer 10 mm in diameter was discovered in the center of the post-ESD ulcer. Biopsies revealed large cells with intranuclear inclusion bodies, which stained positive for the anti-CMV antibody. Local TA injections are useful, however, CMV ulcer might occur as adverse events.

Accurate hemostasis with a new endoscopic overtube for emergency endoscopy

Endoscopic hemostasis performed in the emergency room is difficult due to the presence of blood clots and food residue that makes obtaining a clear view of the bleeding vessel difficult. We experienced the efficacy of a newly developed inverted overtube to shorten the hemostatic time and obtain a clear endoscopic view with upper gastrointestinal bleeding patient who were transferred by ambulance car and required emergency endoscopy. The technique improved the endoscopic views and enabled us to perform the hemostatic procedures from the conventional standing position while freely and easily changing the patients position. The presence of blood clots and food residue in the gastric fornix or upper gastric body makes identifying a bleeding exposed vessel impossible. This set-up significantly shortened the procedure time. The inverted overtube helped us obtain a clear view in patients who were laid in the right lateral position. Rapid identification of exposed vessels resulted in success of hemostasis.

New flexible endoscopic full-thickness suturing device: a triple-arm-bar suturing system.

BACKGROUND AND STUDY AIM A reliable full-thickness suturing device is necessary for pure natural orifice transluminal endoscopic surgery (NOTES). The present study focused on assessing the reliability of a new suturing device. METHODS A total of 60 single sutures were tested to close 5-cm incisions in 8-cm square pieces of resected swine stomach. Each incision was sutured by an over-the-scope clip (OTSC; n = 20), a single hand-sewn stitch (n = 20), or a single triple-arm-bar suturing system (TBSS) stitch. The maximum pulling force durability (MPD) of each suture was tested. To assess the reliability of the TBSS for endoscopic full-thickness resection (EFTR), 60 EFTRs of 50 mm diameter were performed on excised swine stomachs. After EFTR, full-thickness sutures were made using 3-stitch OTSCs (n = 20), 10-stitch hand-sewn sutures (n = 20), or 10-stitch TBSS sutures (n = 20). Outcomes were the MPD test for both single stitch and multiple stitch applications and the suturing time for single-stitch sutures. RESULTS In the single-stitch MPD tests, there were significant differences between OTSCs and hand-sewn sutures (P = 0.0002) and between OTSCs and TBSS sutures (P = 0.0001), but no significant difference between hand-sewn and TBSS sutures. The multiple-stitch sutures revealed significant differences between OTSCs and hand-sewn sutures (P = 0.0039), and between OTSCs and TBSS sutures (P = 0.013). There was no significant difference between hand-sewn and TBSS sutures. There were significant differences in suture times between OTSC, hand-sewn sutures, and TBSS sutures (P < 0.05). CONCLUSIONS Both single-stitch and multiple-stitch sutures using TBSS have similar strength to hand-sewn sutures. TBSS is a reliable suturing device.

Differences in the Characteristics of Barrett’s Esophagus and Barrett’s Adenocarcinoma between the United States and Japan

In Europe and the United States, the incidence of esophageal adenocarcinoma has increased 6-fold in the last 25 years and currently accounts for more than 50% of all esophageal cancers. Barretts esophagus is the source of Barretts adenocarcinoma and is characterized by the replacement of squamous epithelium with columnar epithelium in the lower esophagus due to chronic gastroesophageal reflux disease (GERD). Even though the prevalence of GERD has recently been increasing in Japan as well as in Europe and the United States, the clinical situation of Barretts esophagus and Barretts adenocarcinoma differs from that in Western countries. In this paper, we focus on specific differences in the background factors and pathophysiology of these lesions.