Risk factors for bleeding after endoscopic submucosal dissection of colorectal neoplasms

AIM:To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection(ESD)treatment for colorectal neoplasms.METHODS:We retrospectively reviewed the medical records of 317 consecutive patients with 325 lesions who underwent ESD for superficial colorectal neoplasms at our hospital from January 2009 to June2013.Delayed post-ESD bleeding was defined as bleeding that resulted in overt hematochezia 6 h to 30d after ESD and the observation of bleeding spots as confirmed by repeat colonoscopy or a required blood transfusion.We analyzed the relationship between risk factors for delayed bleeding following ESD and the following factors using univariate and multivariate analyses:age,gender,presence of comorbidities,use of antithrombotic drugs,use of intravenous heparin,resected specimen size,lesion size,lesion location,lesion morphology,lesion histology,the device used,procedure time,and the presence of significant bleeding during ESD.RESULTS:Delayed post-ESD bleeding was found in14 lesions from 14 patients(4.3%of all specimens,4.4%patients).Patients with episodes of delayed postESD bleeding had a mean hemoglobin decrease of2.35 g/dL.All episodes were treated successfully using endoscopic hemostatic clips.Emergency surgery was not required in any of the cases.Blood transfusion was needed in 1 patient(0.3%).Univariate analysis revealed that lesions located in the cecum(P=0.012)and the presence of significant bleeding during ESD(P=0.024)were significantly associated with delayed post-ESD bleeding.The risk of delayed bleeding was higher for larger lesion sizes,but this trend was not statistically significant.Multivariate analysis revealed that lesions located in the cecum(OR=7.26,95%CI:1.99-26.55,P=0.003)and the presence of significant bleeding during ESD(OR=16.41,95%CI:2.60-103.68,P=0.003)were independent risk factors for delayed post-ESD bleeding.CONCLUSION:Location in the cecum and significant bleeding during ESD predispose patients to delayed post-procedural bleeding.Therefore,careful and additional management is recommended for these patients.

Development of Helicobacter pylori treatment: How do we manage antimicrobial resistance?

Helicobacter pylori(H. pylori) antimicrobial resistance is an urgent, global issue. In2017, the World Health Organization designated clarithromycin-resistant H.pylori as a high priority bacterium for antibiotic research and development. In addition to clarithromycin, resistance to metronidazole and fluoroquinolones has also increased worldwide. Recent international guidelines for management of H.pylori infection recommend bismuth or non-bismuth quadruple therapy for 14 d as a first-line treatment for H. pylori in areas of high clarithromycin and/or metronidazole resistance. Although these treatment regimens provide acceptable H. pylori eradication rates, the regimens used should not contribute to future resistance of H. pylori to antimicrobials. Moreover, these regimens can promote resistance, due to prolonged therapy with multiple antibiotics. A new strategy that can eradicate H. pylori as well as reduce the antibiotics used is required to prevent future antimicrobial resistance in H. pylori. Dual-therapy with vonoprazan and amoxicillin could be a breakthrough for H. pylori eradication in an era of growing antimicrobial resistance. This regimen may provide a satisfactory eradication rate of H. pylori and also minimize antimicrobial resistance due to single antibiotic use and the strong inhibitory effect of vonoprazan on gastric acid secretion.

Ultrasound-guided vs endoscopic ultrasound-guided fine-needle aspiration for pancreatic cancer diagnosis

AIM: To clarify the effectiveness and safety of endo- scopic ultrasound-guided fine-needle aspiration (EUS-FNA) for the diagnosis of pancreatic cancer (PC). METHODS: Patients who were diagnosed with unresectable, locally advanced or metastatic PC between February 2006 and September 2011 were selected for this retrospective study. FNA biopsy for pancreatic tumors had been performed percutaneously under extracorporeal ultrasound guidance until October 2009; then, beginning in November 2009, EUS-FNA has been performed. We reviewed the complete medical records of all patients who met the selection criteria for the following data: sex, age, location and size of the targeted tumor, histological and/or cytological findings, details of puncture procedures, time from day of puncture until day of definitive diagnosis, and details of severe adverse events. RESULTS: Of the 121 patients who met the selection criteria, 46 had a percutaneous biopsy (Group A) and 75 had an EUS-FNA biopsy (Group B). Adequate cytological specimens were obtained in 42 Group A patients (91.3%) and all 75 Group B patients (P=0.0192), and histological specimens were obtained in 41 Group A patients (89.1%) and 65 Group B patients (86.7%). Diagnosis of malignancy by cytology was positive in 33 Group A patients (78.6%) and 72 Group B patients (94.6%) (P=0.0079). Malignancy by both cytology and pathology was found in 43 Group A (93.5%) and 73 Group B (97.3%) patients. The mean period from the puncture until the cytological diagnosis in Group B was 1.7 d, which was significantly shorter than that in Group A (4.1 d) (P < 0.0001). Severe adverse events were experienced in two Group A patients (4.3%) and in one Group B patient (1.3%). CONCLUSION: EUS-FNA, as well as percutaneous needle aspiration, is an effective modality to obtain cytopathological confirmation in patients with advanced PC.

Endoscopic diagnosis and treatment of superficial nonampullary duodenal tumors

The diagnostic and treatment guidelines of superficial non-ampullary duodenal tumors have not been standardized due to their low prevalence.Previous reports suggested that a superficial adenocarcinoma(SAC) should be treated via local resection because of its low risk of lymph node metastasis,whereas a highgrade adenoma(HGA) should be resected because of its high risk of progression to adenocarcinoma.Therefore,pretreatment diagnosis of SAC or HGA is important to determine the appropriate treatment strategy.There are certain endoscopic features known to be associated with SAC or HGA,and current practice prioritizes the endoscopic and biopsy diagnosis of these conditions.Surgical treatment of these duodenal lesions is often related to high risk of morbidity,and therefore endoscopic resection has become increasingly common in recent years.Endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) are the commonly performed endoscopic resection methods.EMR is preferred due to its lower risk of adverse events;however,it has a higher risk of recurrence than ESD.Recently,a new and safer endoscopic procedure that reduces adverse events from EMR or ESD has been reported.

Clinical impact of endoscopy position detecting unit(UPD-3) for a non-sedated colonoscopy

AIM:To evaluate whether an endoscopy position detecting unit(UPD-3) can improve cecal intubation rates, cecal intubation times and visual analog scale(VAS) pain scores, regardless of the colonoscopist's level of experience.METHODS:A total of 260 patients(170 men and 90women)who underwent a colonoscopy were divided into the UPD-3-guided group or the conventional group(no UPD-3 guidance).Colonoscopies were performed by experts(experience of more than 1000colonoscopies)or trainees(experience of less than 100colonoscopies).Cecal intubation rates,cecal intubation times,insertion methods(straight insertion:shortening the colonic fold through the bending technique;roping insertion:right turn shortening technique)and patient discomfort were assessed.Patient discomfort during the endoscope insertion was scored by the VAS that was divided into 6 degrees of pain.RESULTS:The cecum intubation rates,cecal intubation times,number of cecal intubations that were performed in<15 min and insertion methods were not significantly different between the conventional group and the UPD-3-guided group.The number of patients who experienced pain during the insertion was markedly less in the UPD-3-guided group than in the conventional group.Univariate and multivariate analysis showed that the following factors were associated with lower VAS pain scores during endoscope insertion:insertion method(straight insertion)and UPD-3guidance in the trainee group.For the experts group,univariate analysis showed that only the insertion method(straight insertion)was associated with lower VAS pain scores.CONCLUSION:Although UPD-3 guidance did not shorten intubation times,it resulted in less patient painduring endoscope insertion compared with conventional endoscopy for the procedures performed by trainees.

Endoscopic resection for residual lesion of metastatic gastric cancer:A case report

BACKGROUND Chemotherapy is a standard strategy for stage IV gastric cancer patients.However, some cases cannot undergo conversion surgery because of their frailty,even if the patients had response to chemotherapy. For these patients, local tumor progression is a problem. We report here the case of a patient whose residual gastric cancer was resected through endoscopic submucosal dissection(ESD)after concomitant chemotherapy for metastatic gastric cancer.CASE SUMMARY An 85-year-old male complained of difficulty swallowing, and examination revealed gastric cancer with multiple liver metastases. Although he received concomitant chemotherapy, a residual tumor was observed in the primary lesion while the metastatic lesions disappeared completely. Conversion surgery was considered optional treatment; however, he could not undergo that because of advanced age and comorbidities. Thus, we performed ESD to treat the residual tumor. As a result, we resected the residual lesion completely. The patient has been alive for 29 mo since ESD, without recurrence.CONCLUSION We achieved local control using ESD, and these findings may provide therapeutic improvements both in local control and patient survival outcomes.

Endoscopic mucosal resection vs endoscopic submucosal dissection for superficial non-ampullary duodenal tumors

BACKGROUND The selection of endoscopic treatments for superficial non-ampullary duodenal epithelial tumors(SNADETs)is controversial.AIM To compare the efficacy and safety of endoscopic mucosal resection(EMR)and endoscopic submucosal dissection(ESD)for SNADETs.METHODS We retrospectively analyzed the data of patients with SNADETs from a database of endoscopic treatment for SNADETs,which included eight hospitals in Fukuoka,Japan,between April 2001 and October 2017.A total of 142 patients with SNADETs treated with EMR or ESD were analyzed.Propensity score matching was performed to adjust for the differences in the patient characteristics between the two groups.We analyzed the treatment outcomes,including the rates of en bloc/complete resection,procedure time,adverse event rate,hospital stay,and local or metastatic recurrence.RESULTS Twenty-eight pairs of patients were created.The characteristics of patients between the two groups were similar after matching.The EMR group had a significantly shorter procedure time and hospital stay than those of the ESD group[median procedure time(interquartile range):6(3-10.75)min vs 87.5(68.5-136.5)min,P<0.001,hospital stay:8(6-10.75)d vs 11(8.25-14.75)d,P=0.006].Other outcomes were not significantly different between the two groups(en bloc resection rate:82.1%vs 92.9%,P=0.42;complete resection rate:71.4%vs 89.3%,P=0.18;and adverse event rate:3.6%vs 17.9%,P=0.19,local recurrence rate:3.6%vs 0%,P=1;metastatic recurrence rate:0%in both).Only one patient in the ESD group underwent emergency surgery owing to intraoperative perforation.CONCLUSION EMR has significantly shorter procedure time and hospital stay than ESD,and provides acceptable curability and safety compared to ESD.Accordingly,EMR for SNADETs is associated with lower medical costs.

Clutch Cutter knife efficacy in endoscopic submucosal dissection for early gastric neoplasms

AIM To compare the outcomes of endoscopic submucosal dissection(ESD) for gastric neoplasms using Clutch Cutter(ESD-C) or other knives(ESD-O).METHODS This was a single-center retrospective study. Gastric neoplasms treated by ESD between April 2016 and October 2017 at Kitakyushu Municipal Medical Center were reviewed. Multivariate analyses and propensity score matching were used to reduce biases. Covariates included factors that might affect outcomes of ESD, including age, sex, underlying disease, anti-thrombotic drugs use, tumor location, tumor position, tumor size, tumor depth, tumor morphology, tumor histology, ulcer(scar), and operator skill. The treatment outcomes were compared among two groups. The primary outcome was ESD procedure time. Secondary outcomes were en bloc, complete, and curative resection rates, and adverse events rates including perforation and delayed bleeding.RESULTS A total of 155 patients were included in this study; 44 pairs were created by propensity score matching. Background characteristics were quite similar among two groups after matching. Procedure time was significantly shorter for ESD-C(median; 49 min) than for ESD-O(median; 88.5 min)(P < 0.01). However, there was no significant difference in treatment outcomes between ESD-C and ESD-O including en bloc resection rate(100% in both groups), complete resection rate(100% in both groups), curative resection rate(86.4% vs 88.6%, P = 0.730), delayed bleeding(2.3% vs 6.8%, P = 0.62) and perforation(0% in both groups).CONCLUSION ESD-C achieved shorter procedure time without an increase in complication risk. Therefore, ESD-C could become an effective ESD option for gastric neoplasms.

Assistant skill in gastric endoscopic submucosal dissection using a clutch cutter

BACKGROUND A clutch cutter is a scissor-type knife used in endoscopic submucosal dissection(ESD)for gastrointestinal tract tumors.The assistant during the ESD using a clutch cutter(ESD-C)needs to rotate the device and grasp the target tissue appropriately;therefore,the assistant’s skill may affect the technical outcomes of ESD-C.AIM To determine how assistant skill level affected the technical outcomes of gastric ESD-C using an ex vivo porcine training model.METHODS In this pilot study,mock lesions of 15-30 mm in diameter were created in the middle or lower third of the porcine stomach.A total of 32 ESD-C procedures were performed by 16 trainees.Each trainee operator performed two ESD-C procedures;one ESD-C was assisted by an expert(ESD-C-E),and the other was assisted by a non-expert(ESD-C-NE).The total procedure time of the ESD was set as the primary outcome,and en bloc resection rate,complete procedure rate,perforation rate,and each procedure time/speed for mucosal incision or submucosal dissection were set as the secondary outcomes.In addition,we investigated factors associated with the difficulty of ESD including incompletion of ESD procedure,a long procedure time(≥20 min)or intraoperative perforation.RESULTS The median total procedure time of the ESD-C-E was significantly shorter than that of the ESD-C-NE(12.9 min vs 21.9 min,P=0.001).The en bloc resection rate was 100%in both groups.Complete resection rates of the ESD-C-E and ESD-C-NE groups were 100%and 93.8%,respectively.No intraoperative perforation was observed in both groups.In the multivariate analysis,assistant skill was significantly associated with the difficulty of ESD,with the highest odds ratio of 16.5.CONCLUSION Assistance by an expert is an important factor when trainees perform ESD-C procedures.

Effectiveness and safety of sedation in gastrointestinal endoscopy:An opinion review

Although endoscopy is a less invasive procedure than surgery,patients can experience pain without sedation.Patients expect reduced pain during endoscopies from effective and safe sedatives.Midazolam and propofol are used for endoscopic sedation in many countries and regions.Midazolam is a widely available benzodiazepine,and many clinical trials have shown it to be an effective sedative.However,patients who are sedated with midazolam require rest in the recovery room due to its relatively long half-life,and an antagonist such as flumazenil may need to be administered in cases of deep or prolonged sedation.Propofol is a short-acting sedative with a short half-life and a quick recovery time.Therefore,the use of propofol has been increasing.However,propofol has a narrow margin of safety and often induces adverse effects such as respiratory depression.Also,propofol has no specific antagonist,and should be administered by an anesthesiologist or an endoscopist familiar with anesthesia.Remimazolam,which is a novel ultra-short-acting benzodiazepine,has recently gained attention.Remimazolam has a short half-life and an antagonist.Both effective and safe sedation is desired in accordance with the increasing need for sedative endoscopies.Therefore,in this review each sedative is summarized.

Field Electron-Emission from a-CN_x:H Films Formed on Al Films Using Supermagnetron Plasma CVD

Hydrogenated amorphous carbon nitride (a-CNx:H) films were formed on p-Si, Al films deposited on n-Si (Al/n-Si) and glass (SiO2) (Al/glass) substrates, using pulsed rf supermagnetron plasma chemical vapor deposition (CVD) with N2/i-C4H10 mixed gases. The rf powers (13.56 MHz) of both the upper and lower electrodes were modulated by a 2.5-kHz pulse at a duty ratio of 12.5%. N2 gas concentration was controlled at 70%. The optical band gap of a-CNx:H films was about 0.75 eV. The a-CNx:H films deposited on substrates of p-Si, Al/n-Si and Al/glass showed low threshold emission electric fields (ETH) of 10, 13 and 12 V/μm, respectively. The a-CNx:H film deposited on low-cost Al film (Al/glass) showed a sufficiently low ETH of 12 V/μm, eliminating the need for high-cost p-Si substrates.

Efficacy and safety of grasping forceps-assisted endoscopic resection for gastric neoplasms:A multi-centre retrospective study

BACKGROUND Endoscopic submucosal dissection(ESD)is widely accepted for early gastric cancer(EGC)without lymph node metastasis,although ESD is challenging,even for small lesions,in the greater curvature(GC)of the upper(U)and middle(M)thirds of the stomach.Grasping forceps-assisted endoscopic resection(GF-ER)is a type of endoscopic mucosal resection that is performed via a double-channel endoscope.AIM To investigate the safety and efficacy of GF-ER vs ESD in the GC of the stomach’s U and M regions.METHODS We retrospectively reviewed the medical records of 506 patients who underwent ER of 522 EGC lesions in the stomach’s U and M regions in three institutions between January 2016 and May 2020.Nine lesions from eight patients who underwent GF-ER for EGC(the GF-ER group)were compared to 63 lesions from 63 patients who underwent ESD(the ESD group).We also performed a subgroup analysis of small lesions(≤10 mm)in 6 patients(7 lesions)from the GF-ER group and 20 patients(20 lesions)from the ESD group.RESULTS There were no statistically significant differences between the GF-ER and ESD groups in the en bloc resection rates(100%vs 100%)and the R0 resection rates(100%vs 98.4%).The median procedure time in the GF-ER group was shorter than that in the ESD group(4.0 min vs 55.0 min,P<0.01).There were no adverse events in the GF-ER group,although five perforations(8.0%)and 1 case of postoperative bleeding(1.6%)were observed in the ESD group.When we only considered lesions that were≤10 mm,the median procedure time in the GF-ER group was still shorter than that in the ESD group(4.0 min vs 35.0 min,P<0.01).There were no adverse events in the GF-ER group,although 1 case of perforation(1.6%)were observed in the ESD group.CONCLUSION These findings suggest that GF-ER may be an effective therapeutic option for small lesions in the GC of the stomach’s U and M regions.

Gastric Mucosal Atrophy Might Be Associated with the Efficacy of First-Line Therapy Using Vonoprazan for <i>Helicobacter pylori</i>

Aim: To investigate the factors related to the effect of eradication therapy with vonoprazan for Helicobacter pylori (H. pylori). Methods: We retrospectively reviewed medical records of H. pylori-positive patients who received first-line (40 mg vonoprazan/60 mg lansoprazole or 20 mg rabeprazole, 1500 mg amoxicillin, 400 mg clarithromycin, all 2/day for 7 days) (n = 4118). H. pylori eradication was assessed by the 13C-urea breath test with success defined as a result of H. pylori eradication therapy using vonoprazan was more effective than standard triple therapy with proton pump inhibitor. Gastric mucosal atrophy was associated with treatment success.