Pancreatic and peripancreatic fluid collection, mainly walled-off necrosis, is a serious late complication of acute pancreatitis and requires drainage in symptomatic cases presenting with infection. Recently, endoscopic ultrasound (EUS)-guided transluminal drainage and direct endoscopic necrosectomy have become standard minimally invasive therapy. Several methods that involve drainage using a dedicated large-diameter biflanged metal stent, additional endoscopic drainage techniques, and the hybrid approach adding percutaneous drainage and necrosectomy have now made it possible to treat almost all cases with endoscopic treatment alone. However, without being restricted to endoscopic treatments, a wide range of options including surgery should be considered. Herein, we survey the present status of endoscopic therapy for pancreatic and peripancreatic fluid collection due to pancreatitis.

A 64-year-old woman who had undergone thyroidectomy and chemoradiation therapy for diffuse large B-cell lymphoma of the thyroid ten years ago, was admitted to our hospital with the complaint of epigastralgia. Upper and lower endoscopy revealed multiple ulcerative lesions on the duodenum, ileum, and colon. The biopsy specimen showed that atypical lymphocytes infiltrated the submucosa with various inflammatory cells. Irregular ulcerative lesions were also present on her oropharynx. Atypical lymphocytes were positive for Epstein-Barr virus (EBV)-encoded small RNA-1. Therefore, she was diagnosed with EBV-positive intestinal lymphoma. It was speculated that her immunodeficient state due to the previous chemoradiation therapy reactivated EBV and caused the onset of intestinal lymphoma.

A 41-year-old man was referred to our hospital for further examination of a tumor in the stomach. Esophagogastroduodenoscopy (EGD) showed a submucosal tumor-like elevated tumor of 2.5 cm in diameter with a reddish deep depression at the lower body of the stomach. In addition, magnified narrow-band imaging showed dilated vessels at the marginal elevated area and a large villous structure and small vessel without change of caliber at the central depressed area of the tumor. The tumor was diagnosed as a neuroendocrine tumor (NET) by endoscopic biopsy. Endoscopic findings including the dilated blood vessels were useful for the correct diagnosis. Computed tomography (CT) detected a swollen lymph node of 6.9 cm in diameter located close to the tumor. Because the tumor was a sporadic type in a patient without underlying diseases, this tumor was diagnosed as type 3 gastric NET. Therefore, we performed distal gastrectomy with lymph node dissection. The pathological diagnosis was NET (G2), pT3N1M0, pStage Ⅲb (ENETS). No recurrence has occurred for 24 months after surgery.

A 78-year-old man presented to our emergency department with massive melena and hemorrhagic shock. Contrast-enhanced CT raised the suspicion of bleeding from the splenic flexure. Because it stopped bleeding naturally, conservative treatment was commenced, but he developed rebleeding and hemorrhagic shock three days after hospitalization. Because the hemorrhagic shock did not improve, we judged that endoscopic hemostasis would be difficult. Abdominal angiography could not detect bleeding diverticula, and emergency surgery was performed. We were able to detect the bleeding diverticulum with a huge visible vessel at the splenic flexure by intraoperative endoscopy, and were able to avoid colectomy by surgical ligation of the feeding artery and suturing all layers of the colonic wall.

Diverticular hemorrhage for which it is difficult to perform endoscopic hemostasis is rare, but we always have to assume that endoscopic hemostasis may be difficult. When we considered the complications and invasion of emergency surgery, this method was very useful.

A 73-year-old man presented to our hospital with right abdominal discomfort. Colonoscopic examination revealed a laterally spreading tumor (LST) in the ascending colon, and endoscopic mucosal resection (EMR) was performed.

One day after EMR was performed, he came to our hospital with the chief complaints of abdominal pain and fever. Laboratory examination showed increased levels of inflammatory markers, and abdominal CT revealed intussusception of the ascending colon.

Colonoscopic examination revealed that the mucosa of the ascending colon was edematous but the intussusception had already reduced spontaneously.

It was strongly suspected that the hemostatic clips and/or the injected solution we used during EMR and the patient’s background of having a mobile cecum caused colonic intussusception after EMR.

We report herein a rare case in which colonic intussusception occurred after EMR.

Here we describe a rare case of ischemic colitis complicated by acute portal vein thrombosis (PVT).

A 55-year-old man visited our hospital because of the sudden onset of lower abdominal pain and hematochezia. Abdominal contrast-enhanced computed tomography identified a density change in the area of the right branch of the portal vein, suggesting acute PVT. Colonoscopy revealed circumferential and continuous mucosal edema and hemorrhagic erythema in the descending colon. Fluoroscopic examination of the large intestine, using a water-soluble contrast agent, revealed a thumbprint sign, approximately 20 cm in length, in the descending colon. Based on both the clinical course and examination results, the patient was diagnosed with ischemic colitis. In this case, there was no history of liver disease or of any underlying condition that might have caused PVT. Furthermore, coagulation abnormalities were not observed. Therefore, the PVT was considered to have been caused by ischemic colitis. Colonoscopy performed on day 13 of the hospital stay showed marked improvement, and several longitudinal ulcer scars were observed. The patient was deemed to have made satisfactory progress and was discharged on day 16. Regarding the PVT, anticoagulant therapy was initiated during hospitalization, and two months later, disappearance of the thrombus was confirmed by abdominal computed tomography and ultrasound Doppler examination.

To the best of our knowledge, this is the second case of ischemic colitis complicated by acute PVT.

We report in detail the progress that has been made in the development and use of the endocytoscopy system (ECS), and introduce the ECS appearance of various esophageal lesions.

The first-generation ECS was developed in 2003 as an ultra-high magnification endoscope (fixed focus, probe) allowing magnification to the cell level. The latest (fourth-generation) ECS offers a hi-vision view with a consecutive increase in magnification to ×500. This ECS makes it possible to observe features at the “conventional endoscopy level”, “microvasculature level” and “cell level” through a gradual increase in magnification using a hand lever during the same examination.

For observation of cells using ECS, vital staining with toluidine blue, etc., is necessary. In the esophagus, cell staining can be observed just after spraying the dye into the esophageal lumen. After vital staining, it is possible to observe cells on the mucosal surface by bringing the lens of the ECS into contact with the target mucosa.

We propose a type classification to distinguish malignant lesions from benign lesions efficiently : (1) Type 1, surface epithelial cells have a low nucleus/cytoplasm (N/C) ratio and a low cell density. No nuclear abnormality is evident. (2) Type 2, there is a high nuclear density but no evident nuclear abnormality. No clear borders between cells are evident. (3) Type 3, evidently increased nuclear density and nuclear abnormality.

On the basis of in vivo observation, the sensitivity and specificity of ECS for malignant lesions by an endoscopist were 93.6％ and 94.6％, respectively, if Type 3 was considered malignant. With regard to a pathologist’s interpretation of the ECS images, the sensitivity and specificity for malignant lesions were 93.6％ and 98.8％, respectively. On the basis of ECS images, neither the endoscopist nor the pathologist was able to clearly distinguish regenerative squamous epithelium in gastroesophageal reflux disease and esophagitis after radiotherapy from esophageal cancer. In such cases, histological examination of biopsy specimens would be necessary in addition to ECS diagnosis.

ECS observation of esophageal lesions will facilitate “optical biopsy”, and allow omission of histological examination of biopsy specimens in many cases. However, as ECS observation is limited to observation of cells on the mucosal surface, this must be recognized as a limitation of this new technology.

To perform effective and safe endoscopic submucosal dissection (ESD) of large gastric neoplasms, an appropriate endoscopic view is essential; however, there are some locations in which it is difficult for the tip of the endoscope to reach the target. Some tumors are located at sites where it is difficult to get the tip of the endoscope close to the tumor, such as the lesser curvature of the gastric body and the angulus. To facilitate ESD treatment in these locations that are difficult to reach, it is important to change the patient’s position or control the volume of air in the stomach. In cases in which it is difficult to obtain an appropriate endoscopic view with these methods, a multiple-bending endoscope or a one-sided, expandable balloon (Air assist) that can be attached to a conventional endoscope makes it possible to reach sites reliably that are difficult to approach with conventional endoscopes.

Background and Aim : The aim of the present study was to evaluate the efficacy and safety of sedation with a combination of propofol (PF) and dexmedetomidine (DEX) compared with sedation with benzodiazepines in esophageal endoscopic submucosal dissection (ESD).

Methods : We retrospectively reviewed clinical data for 40 consecutive patients who had undergone esophageal ESD at the Yokohama City University Hospital between July 2012 and August 2014. Of these patients, 20 were sedated with benzodiazepines (conventional group) and another 20 patients were sedated with a combination of PF and DEX (combination group). Parameters for efficacy and safety of sedation were evaluated by comparisons between the two groups.

Results : Median procedural times in the combination group were shorter than those in the conventional group (61min vs 89 min, P = 0.03), and the percentage of patients who showed restlessness in the combination group was significantly lower than that in the conventional group (25% vs 65%, P = 0.025). Incidences of hypotension and bradycardia in the combination group were higher than those in the conventional group (60% vs 15%, P＝0.008, and 60% vs 15%, P = 0.008, respectively).

Conclusion : This retrospective study suggests that a combination of PF and DEX may provide stable deep sedation with less body movement than benzodiazepines during esophageal ESD.