Superficial non-ampullary duodenal epithelial tumors (SNADET) are increasingly being detected and treated in recent years. In view of the high invasiveness of pancreaticoduodenectomy, endoscopic resection (ER) is being accepted for treatment of SNADET. However, duodenal ER is occasionally technically challenging owing to submucosal fibrosis secondary to biopsy performed before treatment. Underwater endoscopic mucosal resection involves filling of the duodenal lumen with water or saline and resection of the lesion using a snare without submucosal injection. Cold polypectomy is useful to resect target lesions physically without the use of radiofrequency current and may serve as a safe and simple method for SNADET, although the resectability rate of this technique may be insufficient. Endoscopic submucosal dissection of SNADET is technically challenging and is associated with a significantly high risk of delayed adverse events. However, recent reports describe novel techniques, such as the water pressure and pocket creation methods, which are associated with improved outcomes. Furthermore, closure of the mucosal defect after resection is shown to significantly reduce the rate of delayed adverse events after duodenal ER. Further studies are warranted to clarify the curative criteria, long-term results, and appropriate surveillance methods.

Surgical resection with lymph node dissection is the current standard of treatment for high-risk lower rectal submucosal invasive cancer after endoscopic or surgical local resection. However, surgery affects the patientsʼ quality of life due to stoma placement or impaired anal sphincter function. The 5-year disease-free survival rate of patients who underwent adjuvant chemoradiotherapy (CRT) after local resection is comparable to those who underwent surgery. Therefore, we hypothesize that adjuvant CRT, consisting of capecitabine and radiotherapy, can be an option or a new standard of treatment for patients with high-risk lower rectal submucosal invasive cancer after local resection. The Gastrointestinal Endoscopy Study Group and the Colorectal Cancer Study Group of the Japan Clinical Oncology Group (JCOG) planned the study (JCOG1612) aimed at confirming the utility of adjuvant chemoradiotherapy for rectal submucosal invasive cancer after local resection to surgical treatment. JCOG1612 is designed as a multi-institutional, single-arm trial. The primary endpoint is 5-year relapse-free survival (RFS). The secondary endpoints are 10-year RFS; 5-year and 10-year overall survival (OS), 5-year and 10-year local RFS, 5-year and 10-year proportion of anus-preservation without stoma, Wexner score, low anterior resection syndrome score, adverse events, and severe adverse events. During the 4-year trial period, 210 patients will be accrued from about 70 Japanese institutions. The participants will include patients who 1) are aged 20-75 years; 2) have an Eastern Cooperative Oncology Group Scale of Performance Status of 0-1; 3) have undergone complete en bloc resection performed by local resection with vertical margin-negative as the pathological diagnosis; 4) have no lymph node and distant metastasis by diagnostic imaging; and 5) rejected the current standard of treatment (surgical resection with lymph node dissection). The trial treatment is chemotherapy with capecitabine (days 1-5, 8-12, 15-19, 22-26, and 29-33; 1800-3000 mg/day) in combination with radiotherapy (45 Gy in 25 fractions) for primary tumor bed and mesorectum after local resection. All registered patients will be followed-up for at least 10 years after enrolment. Colonoscopy, physical examination, and enhanced computed tomography of the chest, abdomen, and pelvis will be performed every 6 months for the first 3 years after the termination of protocol treatment, and yearly thereafter for the next 7 years. This study was approved by the Accredited Clinical Research Review Board on October 15, 2018; published on Japan Registry of Clinical Trials on January 11, 2019; and registration began on January 16.

Acute hemorrhagic rectal ulcer (AHRU), characterized by sudden painless and massive rectal bleeding in bedridden patients with severe comorbid illnesses, is increasingly being reported in Asia, particularly in Japan.

AIM: We investigated the clinical and endoscopic features of AHRU and the risk factors associated with a refractory and fatal course of this condition.

METHOD: We retrospectively reviewed the records of 44 patients with endoscopically documented AHRU between January 2016 and December 2017. We recorded the following data: (1) Patientsʼ background. (2) Endoscopic findings and hemostasis. (3) Rebleeding after primary hemostatic treatment. (4) Number of deaths.

RESULTS: (1) Most patients were elderly individuals (median age 78 years). We observed a relatively high number of bedridden patients with Eastern Cooperative Oncology Group performance status 3 or 4 (n=37, 84.1%). Comorbidities associated with AHRU included cardiovascular (n=10), cerebrovascular (n=9), and orthopedic diseases (n=7). (2) The ulcerative patterns of AHRU were endoscopically classified into the irregular (n=23), nearly circular (n=12), and Dieulafoy-like (n=9) lesions. Hemorrhage that necessitated hemostatic intervention occurred in >50% of patients (n=25, 56.8%); endoscopic placement of hemostatic clips was the most common method used (n=19). Most endoscopic primary hemostatic procedures were successful (96.0%). (3) Rebleeding occurred in 7 patients after endoscopic hemostasis. Steroid use was a risk factor for rebleeding after primary hemostasis (p=0.008). (4) Ten patients (22.7%) with AHRU died during hospitalization. Dialysis was identified as a risk factor for in-hospital mortality among patients with AHRU (p<0.001).

CONCLUSION: Endoscopic primary hemostasis was successful; however, some patients showed a refractory or fatal course. Notably, steroid use was a risk factor for rebleeding after hemostasis treatment, and dialysis was a risk factor for death in patients with AHRU and a complicated clinical course.

A 78-year-old patient with a pulmonary large cell carcinoma was referred to our department because of hypochromic microcytic anemia after receiving 30 courses of pembrolizumab therapy. Esophagogastroduodenoscopy revealed an esophageal ulcer from the cervical part to the middle thoracic part. Histologic findings showed ulcerative esophagitis with infiltration of neutrophils and granulation tissue. Drug-induced esophagitis and infectious esophagitis were excluded because of the patientʼs drug history and laboratory data. We diagnosed an esophageal immune-related adverse event induced by pembrolizumab. Treatment with vonoprazan was initiated, and pembrolizumab was discontinued. However, he subsequently complained of grade 3 dysphagia, and treatment of colitis by immune checkpoint inhibitors as well as Ⅳ methylprednisolone 1 mg/kg/day was initiated. His dysphagia gradually resolved, and tapering of methylprednisolone therapy was planned. After methylprednisolone therapy for 12 weeks, his symptoms and the esophageal ulcer had completely resolved. Pembrolizumab treatment was not reinitiated. Esophageal immune-related adverse events induced by immune check point inhibitors are rare, but physicians should be aware of this rare manifestation.

A Japanese man underwent resection of the lower esophagus and gastric cardia, followed by jejunal interposition reconstruction for refractory reflux esophagitis and annual esophagogastroduodenoscopy for follow-up. Esophagogastroduodenoscopy performed at 87 years of age revealed a white area (approximately 10 mm in diameter) with a clear boundary in the gastric fornix. Narrow-band imaging showed a lesion that was white-green in color without a glandular structure on the surface. We diagnosed squamous metaplasia of the stomach based on biopsy findings. Annual esophagogastroduodenoscopy showed a slight increase in the area of squamous metaplasia over the course of follow-up. Evaluation performed at 92 years of age revealed a lesion with a map-like morphology. Gastric squamous metaplasia rarely occurs discontinuously from the esophageal mucosa; however, prompt endoscopic diagnosis is possible based on the characteristic morphology of this lesion.

The patient was a 64-year-old woman. Esophagogastroduodenoscopy for abdominal symptoms revealed a 30-mm red-colored protuberance surrounded by submucosal tumor-like elevations at the gastric fornix. On the basis of the findings obtained after total gastrectomy, she was diagnosed with advanced gastric cancer caused by a low-grade, well-differentiated gastric adenocarcinoma with the gastric phenotype on the surface. This disease often occurs in the stomach without H. pylori infection, or appears in the non- atrophic fundic gland area after H. pylori eradication. Therefore, this disease has been receiving much attention recently. Most case reports on this disease describe patients with early-stages gastric cancer, and it is considered to have a good prognosis, but we encountered a rare case of advanced cancer instead. The patient in this case showed advanced gastric cancer manifesting as a low-grade, well-differentiated gastric adenocarcinoma with the gastric phenotype on the surface and a poorly differentiated adenocarcinoma component in the deepest part, indicating a peculiar morphology. We report this case with a literature review of the endoscopic and histopathological features.

A 63-year-old man showed a duodenal elevated lesion on esophagogastroduodenoscopy, which was suspected to be an adenocarcinoma or adenoma on the basis of endoscopic findings. He was subsequently referred to our hospital for further examination and treatment. Endoscopic ultrasonography showed a hypoechoic area inside the tumor. The tumor was located on the second part of the duodenum and had a depression on its lateral side. On the basis of these findings, the patient underwent endoscopic mucosal resection. Histological examination of the resected specimen revealed that the depressed area was a tubular adenoma, and the luminal side of the duodenum and cystic area shared muscularis mucosae. The lesion was eventually diagnosed as duodenal duplication or intraluminal duodenal diverticulum with tubular adenoma. Although extremely rare, these diseases should be considered in the differential diagnosis of duodenal elevated lesions.

Bleeding from isolated gastric varices (iGV) is fatal. Thus, preventive treatment for iGV is crucial. The CA/EO method is a well-established endoscopic technique that has been used for the treatment of iGV; this technique uses a tissue adsorbent cyanoacrylate (CA) and a sclerosingagent, ethanolamine oleate (EO). In the recent years, a new technique of endoscopic ultrasound (EUS)-guided coil placement has shown promising results. This method enables safe and effective treatment because the puncture is performed while directly observing the iGV lumen with EUS and the coil (coil size is 150% of diameter of iGV)can be deployed with a needle under the guidance of the EUS. In this study, we performed EUS-guided coil deployment with sclerotherapy (EUS-CS), followed by the injection of EO after coil placement to embolize not only iGV but also the blood tract. This method is very effective, but it is necessary to evaluate and understand the hemodynamics of portal hypertension using various diagnostic imaging methods before treatment.

Significant technological advances have resulted in the availability of fine endoscopes and their peripheral devices in recent years.

Conventionally, ultrathin transnasal endoscopes are used only for diagnostic purposes. However, this device may score over conventional endoscopes for therapeutic endoscopy in specific cases.

Following are the indications for the use of ultrathin transnasal endoscopes: 1) to avoid sedation, 2) patients in whom insertion of a usual (standard) therapeutic endoscope is impossible owing to stenosis and, 3) to approach a pharyngeal lesion.

In this article, we describe details of the endoscopic submucosal dissection procedure using a ultrathin transnasal endoscope, which is increasingly being accepted for its potential utility in therapeutic endoscopy.

The coronavirus disease pandemic has significantly affected delivery of medical care in Japan, including gastrointestinal endoscopy services. In this study, we analyzed the data provided to the Japan Endoscopy Database and its effect. Gastrointestinal endoscopy was significantly affected by the initial spread of infection in April 2020; the number of gastrointestinal endoscopy procedures was reduced by nearly 50%. Specifically, upper and lower gastrointestinal endoscopy and endoscopic treatment of the lower gastrointestinal tract were significantly affected. In contrast, endoscopic retrograde cholangiopancreatography-related procedures, which are usually performed on an emergency basis and for cancer treatment, were relatively unaffected. However, from May 2020, following gradual recovery from the public health crisis, the number of cases returned to the pre-pandemic level (cases during the previous year until December 2020). Thereafter, the third wave from the end of 2020 to the beginning of 2021, followed by the fourth wave in May 2021, and the fifth wave in August 2021, led to a remarkably large increase in the number of infected patients; however, we did not observe a significant reduction in the number of endoscopic procedures performed, in contrast to the situation in May 2020. From the social viewpoint, the pandemic significantly affected diagnostic evaluation; however, normalcy was rapidly restored owing to the combined efforts of gastrointestinal endoscopists. It will be important to monitor the effects of the pandemic on gastrointestinal endoscopy practice in 2021.

Background and aim: “Time out” is a brief pause preceding esophagogastroduodenoscopy (EGD) to confirm the identity of the patient, and the assessment of “discharge criteria” after EGD with sedation can facilitate efficient examinations while maintaining patient safety. However, in Japan, the extent of their applicability in clinical practice is unclear. This study aimed to clarify the actual implementation status of “time out” and “discharge criteria.”

Methods: We distributed a questionnaire survey to institution-based endoscopists in Japan.

Results: A total of 66 institutions provided valid answers, which revealed the following statistics. As a component of perioperative management of EGD, “time out” was introduced in 61% of the institutions. The answers provided for each item of the questionnaire varied among institutions. More than 60% of the institutions adopted patient names, examination contents, anti-thrombotic drugs, known allergies, and underlying diseases. In addition, “discharge criteria” was introduced in 65% of the institutions. Trends in the assessment of “discharge criteria” showed that the adoption of “institution-based criteria” (44%) and “anesthesia recovery score” (39%) created by the Japan Gastroenterological Endoscopy Technicians Society were followed by majority of the institutions.

Conclusion: Although “time out” preceding the procedure and “discharge criteria” after sedation are becoming prominent components of perioperative management in EGD, the criteria of these components lack uniformity. Simple and uniform criteria should be created for nationwide implementation.

Over the past two decades, the incidence and prevalence of eosinophilic esophagitis (EoE) have risen rapidly, especially in Western countries, with cases in Japan also showing a gradual increase in recent years. However, similarities and differences regarding the characteristics of EoE between Western countries and Japan remain to be clearly elucidated. The current clinical guidelines for diagnosis include symptoms related to esophageal dysfunction and dense eosinophilic infiltration in the esophageal epithelium. Most affected patients in Japan are diagnosed incidentally during a medical health check-up and asymptomatic cases with typical endoscopic findings suggestive of EoE are frequently encountered. Clinical characteristics of EoE in Japanese are similar to those seen in Western populations. The predominant symptom is dysphagia, with food impaction extremely rare in Japanese cases. Linear furrows are the most frequently reported characteristic endoscopic finding, while an esophageal stricture or narrow caliber is rarely observed. Treatment strategies for EoE include drugs, dietary restrictions, and endoscopic dilation when the disease is advanced with stricture formation. Although single therapy using a protonpump inhibitor has been shown to achieve symptomatic and histological response in the majority of patients in Japan, no prospective randomized control studies that evaluated drug or elimination diet therapy have been presented. Overall, EoE has similar clinical characteristics between Japanese and Western populations, while disease severity seems to be milder in Japan. Additional studies are necessary to determine genetic factors, natural history of the disease, and treatment efficacy of drugs and elimination diet as compared to Western populations.