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

AIM: To retrospectively review the results of over-thescope 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.

Comparison between combination therapy of percutaneous ethanol injection and radiofrequency ablation and radiofrequency ablation alone for patients with hepatocellular carcinoma

AIM: In the present study, the characteristics of PEI-RFA treatment were further elucidated by analyzing the relationship between the volume of coagulated necrosis and the energy requirement for ablation or the amount of ethanol injected into HCC.METHODS: The volume of coagulated necrosis, total energy requirement and energy requirement for coagulation of per unit volume were examined in the groups of PEI-RFA and RFA alone using the Cool-tip RF system.RESULTS: The results showed that the volume of coagulated necrosis induced was significantly larger in PEI-RFA group than in routine RFA group, when the total energy administered was comparable in both groups.In PEI-RFA, enlargement of coagulated necrosis was admitted in 3 dimensions and the amount of energy requirement per unit volume of coagulated necrosis was negatively correlated with the amount of ethanol injected into HCC.CONCLUSION: These results suggest that, compared to RFA alone, PEI-RFA enables to induce comparable coagulated necrosis with smaller energy requirement, and that PEI-RFA is likely to be less invasive than RFA alone irrespective of inducing enhanced coagulated necrosis.Thus, simple prior injection of ethanol may make RFA treatment more effective and less invasive for the treatment of patients with HCC.

Management of a large mucosal defect after duodenal endoscopic resection

Duodenal endoscopic resection is the most difficult type of endoscopic treatment in the gastrointestinal tract(GI) and is technically challenging because of anatomical specificities. In addition to these technical difficulties, this procedure is associated with a significantly higher rate of complication than endoscopic treatment in other parts of the GI tract. Postoperative delayed perforation and bleeding are hazardous complications, and emergency surgical intervention is sometimes required. Therefore, it is urgently necessary to establish a management protocol for preventing serious complications. For instance, the prophylactic closure of large mucosal defects after endoscopic resection may reduce the risk of hazardous complications. However, the size of mucosal defects after endoscopic submucosal dissection(ESD) is relatively large compared with the size after endoscopic mucosal resection, making it impossible to achieve complete closure using only conventional clips. The over-the-scope clip and polyglycolic acid sheets with fibrin gel make it possible to close large mucosal defects after duodenal ESD. In addition to the combination of laparoscopic surgery and endoscopic resection, endoscopic full-thickness resection holds therapeutic potential for difficult duodenal lesions and may overcome the disadvantages of endoscopic resection in the near future. This review aims to summarize the complications and closure techniques of large mucosal defects and to highlight some directions for management after duodenal endoscopic treatment.

A rare case of hyaline-type Castleman disease in the liver

Castleman disease often develops in the neck, mediastinum and pulmonary hilum. Its onset in the peritoneal cavity is very rare. The patient, a woman in her 70s, was referred to our department for a detailed examination of an abdominal mass. On abdominal ultrasonography, computed tomography scan, magnetic resonance imaging and positron emission tomography, a mass approximately 15 mm in diameter was noted in the hepatic S6. We attempted radical treatment and conducted a laparoscope-assisted right lobectomy. On the basis of histopathological findings, the patient was diagnosed as having hyaline type Castleman disease in the liver, a very rare condition.

Diabetes mellitus and metformin in hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is the leading cause of cancer-related death worldwide. Diabetes mellitus, a risk factor for cancer, is also globally endemic. The clinical link between these two diseases has been the subject of investigation for a century, and diabetes mellitus has been established as a risk factor for HCC. Accordingly, metformin, a first-line oral anti-diabetic, was first proposed as a candidate anti-cancer agent in 2005 in a cohort study in Scotland. Several subsequent large cohort studies and randomized controlled trials have not demonstrated significant efficacy for metformin in suppressing HCC incidence and mortality in diabetic patients; however, two recent randomized controlled trials have reported positive data for the tumor-preventive potential of metformin in non-diabetic subjects. The search for biological links between cancer and diabetes has revealed intracellular pathways that are shared by cancer and diabetes. The signal transduction mechanisms by which metformin suppresses carcinogenesis in cell lines or xenograft tissues and improves chemoresistance in cancer stem cells have also been elucidated. This review addresses the clinical and biological links between HCC and diabetes mellitus and the anti-cancer activity of metformin in clinical studies and basic experiments.

Reduction effect of bacterial counts by preoperative saline lavage of the stomach in performing laparoscopic and endoscopic cooperative surgery

AIM: To investigate the effects of gastric lavage with 2000 mL of saline in laparoscopic and endoscopic cooperative surgery.

A combination therapy of ethanol injection and radiofrequency ablation under general anesthesia for the treatment of hepatocellular carcinoma

AIM: To summarize the effects of laparoscopic ethanol injection and radiofrequency ablation (L-EI-RFA), thora- coscopic (T-EI-RFA) and open-surgery assisted EI-RFA (O-EI-RFA) under general anesthesia for the treatment of hepatocellular carcinoma (HCC). METHODS: Time-lag performance of RFA after ethanol injection (Time-lag PEI-RFA) was performed in all cases. The volume of coagulated necrosis and the applied en- ergy for total and per unit volume coagulated necrosis were examined in the groups treated under general (group G) or local anesthesia (group L). RESULTS: The results showed that the total applied energy and the applied energy per unit volume of whole and marginal, coagulated necrosis were significantly larger in group G than those in the group L, resulting in a larger volume of coagulated necrosis in the group G. The rate of local tumor recurrence within one year was extremely low in group G. CONCLUSION: These results suggest that EI-RFA, un- der general anesthesia, may be effective for the treat- ment of HCC because a larger quantity of ethanol and energy could be applied during treatment under pain- free condition for the patients.

Two rare gastric hamartomatous inverted polyp cases suggest the pathogenesis of growth

Gastric hamartomatous inverted polyps(GHIP)are difficult to diagnose accurately because of inversion into the submucosal layer.GHIP are diagnosed using the pathological characteristics of the tumor,including the fibroblast cells,smooth muscle,nerve components,glandular hyperplasia,and cystic gland dilatation.Although Peutz-Jeghers syndrome,juvenile polyposis,and Cowden disease are hereditary,it is rare to encounter 2 cases of monostotic and asymptomatic gastric hamartomas.The pathogeneses of hamartomatous inverted polyps and inverted hyperplastic polyps remain controversial because of the paucity of reported cases.There are 3 hypotheses regarding the pathogenesis of complete gastric inverted polyps.Based on our experience with 2 successive,rare GHIP cases,we affirm the hypothesis that after a hamartomatous change occurs in the submucosal layer,some of these components are exposed to the gastric mucosa and,consequently,form a hypertrophic lesion.In Case 1,our hypothesis explains why a tiny hypertrophic change was first detected on the top of the submucosal tumor using a detailed narrow band imaging-magnified endoscopy.There was no confirmation that the milky white mucous and calcification structures were exuding directly from the biopsy site like Case 1,and in Case 2 the presence of this mucous was indirectly confirmed during an endoscopic submucosal dissection(ESD).Regarding the pathogenesis of GHIP,a submucosal hamartomatous change may occur prior to the growth of hypertrophic portions.An en bloc resection using ESD is recommended for treatment.

Bleeding duodenal hemangioma: Morphological changes and endoscopic mucosal resection

Recently, the development of endoscopic procedures has increased the availability of minimally invasive treatments; however, there have been few case reports of duodenal hemangioma treated by endoscopic mucosal resection. The present report describes a case of duodenal hemangioma that showed various endoscopic changes over time and was treated by endoscopic mucosal resection. An 80-year-old woman presented with tarry stools and a loss of appetite. An examination of her blood revealed severe anemia, and her hemoglobin level was 4.2 g/dL. An emergency upper gastrointestinal endoscopy was performed. A red, protrusive, semipedunculated tumor (approximately 20 mm in diameter) with spontaneous bleeding on its surface was found in the superior duodenal angle. Given the semipedunculated appearance of the tumor, it was suspected to be an epithelial tumor with a differential diagnosis of hyperplastic polyp. The biopsy results suggested a telangiectatic hemangioma. Because this lesion was considered to be responsible for her anemia, endoscopic mucosal resection was performed for diagnostic and treatment purposes after informed consent was obtained. A histopathological examination of the resected specimen revealed dilated and proliferated capillary lumens of various sizes, which confirmed the final diagnosis of duodenal hemangioma. Neither anemia nor tumor recurrence has been observed since the endoscopic mucosal resection (approximately 1 year). Duodenal hemangiomas can be treated endoscopically provided that sufficient consideration is given to all of the possible treatment strategies. Interestingly, duodenal hemangiomas show morphological changes that are influenced by various factors, such as mechanical stimuli.

Targeting receptor tyrosine kinases in gastric cancer

Molecularly targeted therapeutic agents are constantly being developed and have been shown to be effective in various clinical trials. One group of representative targeted oncogenic kinases, the receptor tyrosine kinases (RTKs), has been associated with gastric cancer development. Trastuzumab, an inhibitor of ERBB2, has been approved for the treatment of gastric cancer, although other receptor tyrosine kinases, such as epidermal growth factor receptor, vascular endothelial growth factor, platelet-derived growth factor receptor, c-Met, IGF-1R and fibroblast growth factor receptor 2, are also activated in gastric cancer. The promising results of the trastuzumab clinical trial for gastric cancer resulted in the approval of trastuzumab-based therapy as a first-line treatment for human epidermal growth factor receptor 2-positive patients. On the other hand, the trial examining bevacizumab in combination with conventional chemotherapy did not meet its primary goal of increasing the overall survival time of gastric cancer patients; however, a significantly higher response rate and a longer progression-free survival were observed in the bevacizumab arm of the trial. Other clinical trials, especially phase III trials that have tested drugs targeting RTKs, such as cetuximab, panitumumab, gefitinib, erlotinib, figitumumab, sorafenib, sunitinib and lapatinib, have shown that these drugs have modest effects against gastric cancer. This review summarizes the recent results from the clinical trials of molecularly targeted drugs and suggests that further improvements in the treatment of advanced gastric cancer can be achieved through the combination of conventional drugs with the new molecularly targeted therapies.

Rectal perforations and fistulae secondary to a glycerin enema:Closure by over-the-scope-clip

Rectal perforations due to glycerin enemas(GE) typically occur when the patient is in a seated or lordotic standing position.Once the perforation occurs and peritonitis results,death is usually inevitable.We describe two cases of rectal perforation and fistula caused by a GE.An 88-year-old woman presented with a large rectal perforation and a fistula just after receiving a GE.Her case was further complicated by an abscess in the right rectal wall.The second patient was a 78-year-old woman who suffered from a rectovesical fistula after a GE.In both cases,we performed direct endoscopic abscess lavage with a saline solution and closed the fistula using an over-the-scope-clip(OTSC) procedure.These procedures resulted in dramatic improvement in both patients.Direct endoscopic lavage and OTSC closure are very useful for pararectal abscess lavage and fistula closure,respectively,in elderly patients who are in poor general condition.Our two cases are the first reports of the successful endoscopic closure of fistulae using double OTSCs after endoscopic lavage of the debris and an abscess of the rectum secondary to a GE.

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

To demonstrate the clinical outcomes of a multicenter experience and to suggest guidelines for choosing a suction method.METHODSThis 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.RESULTSThe 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.CONCLUSIONOTSC 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.

Endoscopic management of a rare granulation polyp in a colonic diverticulum

There are many case reports on colon diverticula that cause irritable bowel syndrome,constipation,bleeding,diverticulitis,stricture due to multiple recurrences of diverticulitis,and perforation.However,few articles have examined neoplasms that arise from a diverticulum,such as adenoma and adenocarcinoma,and there have been no reports of granulation polyps that arise from a colon diverticulum after recurrent diverticulitis.We observed a rare granulation polyp that arose from a diverticulum as a result of repeated episodes of local diverticulitis.Narrow band imaging magnified colonoscopy was very useful to diagnose the polyp as a granulation polyp because of the absence of a pit pattern on the surface of the polyp.We successfully resected the polyp using endoscopic mucosal resection.We inverted the diverticulum,and the resected stalk of the polyp was used to close the diverticulum with an over-thescope clip.If a granulomatous polyp could arise from a diverticulum,differential diagnosis between a colon neoplasm and a granulomatous polyp would not only be difficult but also necessary for suitable endoscopic treatment.

Usefulness of liver infiltrating CD86-positive mononuclear cells for diagnosis of autoimmune hepatitis

AIM： Although the pathogenic mechanism underlying autoimmune hepatitis （AIH） remains unclear, the immune system is thought to be critical for the progression of the disease. Cellular immune responses may be linked to the hepatocellular damage in AIH. Recently, much attention has been focused on the critical functions of costimulatory molecules expressed on mononuclear cells in the generation of effective T cell-mediated immune responses. Analysis of costimulatory molecule expressed on mononuclear cells from the patients with AIH may give us insight into the pathogenic mechanism of hepatocellular damage in AIH. METHODS： Peripheral blood mononuclear cells （PBMC） were taken from the patients with AIH （34 cases） and healthy controls （25 cases）. Uver infiltrating mononuclear cells （LIMCs） were taken from the patients with AIH （18 cases）, the patient with chronic hepatitis C （CH-C） （13 cases） and the patients with fatty liver （2 cases）. Using flow cytometry, the cells were analyzed for the expression of costimulatory molecules, such as CD80, CD86, and CD152 （CTLA-4）. The results were compared with clinical data such as the level of gammaglobulin, histological grade, presence or absence of corticosteroids administration and the response to corticosteroids. RESULTS： The levels of CD80＋, CD86＋ and CD152＋ PBMC were significantly reduced in the patients with AIH as compared with healthy controls. By contrast, those cells were significantly higher in LIMC than in PBMC of the patients with AIH. Especially, the level of CD86＋ LIMC showed a marked increase irrespective of the degree of disease activity in the patients with AIH,although CD86＋ cells were rarely present in PBMC. The levels of CD86＋ cells were present in significantly higher frequency in patients with AIH than in the patients with CH-C. Furthermore, the patients with AIH with high levels of CD86＋ LIMC showed good responses to corticosteroids, whereas 2 cases of AIH with low levels of CD86＋ LIMC did not respond well. CONCLUSION： These results suggest that LIMC overexpressing costimulatory molecules such as CD80 and CD86 appears to play a role in the pathogenesis of AIH. Especially, CD86 molecule expressed on the LIMC may be useful for the diagnosis of AIH and for the prediction of the therapeutic effects of corticosteroids on AIH.

Percutaneous local therapies for hepatocellular carcinoma impair gastric function

Percutaneous local therapies, such as percutaneous ethanol injection （PEI）, microwave coagulation and radiofrequency ablation （RFA）, are frequently used worldwide for the treatment of hepatocellular carcinoma （HCC） because of their high effectiveness. Although these treatment modalities can induce effectively coagulated tumor necrosis in the liver, they may cause adverse effects on extrahepatic abdominal organs. There are, however, no published reports on the influence of percutaneous local therapies on the gastric myenteric activity. Therefore, it is unclear whether or not gastric function is affected by percutaneous local therapies. In this study, to make clear the effect of PEI and RFA on the gastric function, we continuously recorded the gastric myoelectric activity by electrogastrography （EGG） and estimated the effect of percutaneous local therapies for HCC on gastric function.

Novel method to prevent gastric antral strictures after endoscopic submucosal dissection: Using triamcinolone

Endoscopic submucosal dissection(ESD) of large gastric lesions often leads to severe gastric strictures, especially in cases of large ESD in the antrum of the stomach. It has recently been reported that balloon dilation, mucosal incision, and local steroid injections can successfully treat gastric strictures. However, there are some complications with existing methods and decreasing the quality of life. We have developed a novel method to prevent severe gastric strictures that does not involve balloon dilation, mucosal incision, or steroid injections after circumferential ESD. Our original method involves the submucosal injection of a mixed solution composed of triamcinolone acetonide and a general solution of glycerol, hyaluronic acid, and a small amount of indigo carmine and epinephrine dur-ing the ESD procedure; this mixture is called a mixed solution of triamcinolone(MST). According to standard ESD procedures, several milliliters of MST are injected into the submucosal layer for the purpose of elevating the submucosa during ESD resulting in prevention of severe strictures. Our method using MST take several advantages such as MST method suppress inflammation in ulcer from initial phase, prevention of stricture without obstructive symptoms, and does not require several ballooning. Therefore, MST method is safe and gentle, shorten the hospitalization duration. Here, we described two cases in which we prevented severe strictures of the gastric antrum after completing a circumferential ESD using MST without any complications.

Difficulty in differentiating two cases of sigmoid stenosis by diverticulitis from cancer

The incidence of colonic diverticulosis with or without diverticulitis has increased in the Japanese population due to the modernization of food and aging. The rate of diverticulitis in colon diverticulosis ranges from 8.1% to 9.6%. However, few cases of stenosis due to diverticulitis have been reported. These reports suggest that the differentiation between sigmoid diverticulitis and colon cancer is difficult. This report describes two cases of colon stenosis due to diverticulitis that were difficult to differentiate from colon cancer. Case i was a 70-year-old woman with narrowed stools for 1 month who underwent colonofiberscopy （CFS）. CFS revealed a diverticulum and circumferential stenosis in the sigmoid colon. Barium enema revealed a marked, hourglass- shaped, 2-cm circumferential stenosis in the sigmoid colon. Fluorodeoxyglucose （FDG）-positron emission tomography computed tomography （CT） revealed an increased FDG uptake at the affected portion of the sigmoid colon. Sigmoid colon cancer was suspected,and laparoscopic sigmoidectomy was performed. Patho- logical examination demonstrated active inflammation with no evidence of malignancy. Case 2 was a 50-year- old man who presented to a nearby clinic with reduced stool output despite the urge to defecate. CFS detected severe stenosis in the sigmoid colon approximately 25 cm from the dentate line. Contrast-enhanced abdomi- nal CT revealed multiple diverticula, wall thickening, and swelling of the lymph nodes around the peritoneal aorta and the inferior mesenteric artery. A partial sig- moidectomy was performed. Pathological examination of the resected specimen revealed no changes in the mucosal epithelial surface, but a marked infiltration of inflammatory cells was observed.

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 patient's 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 ex-posed vessels resulted in success of hemostasis.

Influence of percutaneous local therapy for hepatocellular carcinoma on gastric function

AIM:To investigate the influence of percutaneous local therapy on gastric myoelectrical activity in patients with hepatocellular carcinomas.METHODS:Forty-four patients with hepatocellular carcinoma(HCC) [27 males and 17 females,ranging in age from 49 to 81 years old(69.7 ± 8.01 years)] who were admitted for percutaneous local therapy were enrolled in this study.We examined clinical abdominal symptoms using the Gastrointestinal Symptom Rating Scale(GSRS) before and 3 d after percutaneous local therapy.We also measured cutaneous fasting and postprandial electrogastrography(EGG) recordings before and 3 d after percutaneous local therapy.RESULTS:We found that the percentage of normogastria in the fasting period was lower in the Child B group than in the Child A group(66.8% ± 8.6% vs 84.0% ± 3.8%).After percutaneous local therapy for HCC,the percentages of normogastria in the fasting period were significantly decreased(81.6% ± 3.5% vs 75.2% ± 4.5%).None of the postprandial EGG parameters changed significantly after percutaneous local therapy for HCC.Percutaneous local therapy for HCC reduced the power ratio(PR).In particular,the PR of tachygastria was significantly decreased after therapy(P < 0.01).However,no significant differences were found in the postprandial EGG parameters.Likewise,no significant differences were found in the calculated GSRS scores obtained from the questionnaire before and after therapy.CONCLUSION:Gastric slow-wave dysrhythmias were induced by percutaneous local therapy in HCC patients,even though the GSRS scores obtained from the questionnaire did not change significantly.

Suitable closure for post-duodenal endoscopic resection taking medical costs into consideration

AIM:To compare closure methods,closure times and medical costs between two groups of patients who had post-endoscopic resection(ER) artificial ulcer floor closures.METHODS:Nineteen patients with duodenal adenoma,early duodenal cancer,and subepithelial tumors that received ER between September 2009 and September 2014 at Kagawa University Hospital and Ehime Rosai Hospital,an affiliated hospital of Kagawa University,were included in the study.We retrospectively compared two groups of patients who received postER artificial ulcer floor closure:the conventional clip group vs the over-the-scope clip(OTSC) group.Delayed bleeding,procedure time of closure,delayed perforation,total number of conventional clips and OTSCs and medical costs were analyzed.RESULTS:Although we observed delayed bleeding in three patients in the conventional clip group,we observed no delayed bleeding in the OTSC group(P = 0.049).We did not observe perforation in either group.The mean procedure times for ulcer closure were 33.26 ± 12.57 min and 9.71 ± 2.92 min,respectively(P = 0.0001).The resection diameters were 18.8 ± 1.30 mm and 22.9 ± 1.21 mm for the conventional clip group and the OTSC group,respectively,with significant difference(P = 0.039).As for medical costs,the costs of all conventional clips were USD $1257 and the costs of OTSCs were $7850(P = 0.005).If the post-ER ulcer is under 20 mm in diameter,a conventional clip closure may be more suitable with regard to the prevention of delayed perforation and to medical costs.CONCLUSION:If the post-ER ulcer is over 20 mm,the OTSC closure should be selected with regard to safety and reliable closure even if there are high medical costs.