Endoscopic retrograde cholangiopancreatography (ERCP) and associated procedures are difficult to perform in patients with surgically altered anatomy because of the extremely long length of afferent limbs that must be traversed to reach the major papilla, the bilio-enteric anastomosis or pancreato-enteric anastomosis. A new insertion method using a double-balloon endoscope or a single-balloon endoscope enables easier access to the afferent duodenal loop in patients with surgically altered anatomy. However, the success rate of endoscopic procedures is still insufficient because the balloon endoscope has a small working channel and is not equipped with an elevator. Further improvements in the balloon endoscope will overcome various problems that are encountered when performing ERCP and associated procedures in patients with surgically altered anatomy.

Background and Aims : The appropriate endoscopic surveillance interval for early detection of metachronous gastric cancer (MGC) following endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) is unclear. This retrospective study investigated the characteristics of MGC following ESD of EGC according to the state of Helicobacter pylori (HP) infection, and the appropriate endoscopic surveillance interval from the viewpoint of stomach preservation.

Methods : This multicenter retrospective cohort study comprised 15 hospitals belonging to the Hokuriku branch of the Japanese Gastroenterological Endoscopy Society (JGES). Patients with EGC who had undergone initial ESD with endoscopic curative resection between 2002 and 2012 and who were followed up for >12 months were divided into three groups : HP-eradicated (successful eradication ; n=455) ; HP-persistent (unsuccessful or no eradication ; n=556) ; and HP-negative (negative in more than two HP tests ; n=291). The cumulative incidence of MGC in these three groups was compared. The proportion of MGC cases that underwent second ESD but did not meet the criteria of endoscopic curative resection as a result of the second ESD was compared according to the endoscopy intervals of 6 months (<9 months), 12 months (9-14 months) and >12 months (>14 months).

Results : During a mean period of 36.3 months, 88 patients developed MGC : 24 (5.3%) in the HP-eradicated group, 47 (8.5%) in the HP-persistent group, and 17 (5.9%) in the HP-negative group. The cumulative incidence of MGC did not differ among the three groups (log rank test : P=0.28), nor did their clinicopathological characteristics. Ten cases of MGC did not meet the criteria of endoscopic curative resection as a result of the second ESD, and the incidence of MGC did not significantly differ according to the endoscopic interval (P=0.61). The endoscopic interval of the 10 cases was distributed around 1 year [median 12.2 (5.5-17.4, range) months].

Conclusion : For the detection of MGC, it is desirable to take the same approach regardless of HP infection. It is anticipated that there will be a certain number of MGCs diagnosed in annual surveillance that do not meet the criteria of endoscopic curative resection as a result of the second ESD. Implementing surveillance at intervals shorter than 12 months may be worthy of consideration from the viewpoint of stomach preservation. To determine the appropriate endoscopic surveillance interval, further prospective studies with greater numbers of cases are warranted.

Follow-up upper gastrointestinal endoscopy in a 67-year-old man with a history of surgery for gastric adenocarcinoma revealed a 5-mm elevated tumor proximal to the major duodenal papilla in 2009. Histopathological findings of a biopsy specimen indicated tubular adenoma, but by 2013, the tumor had increased in size to 20 mm in diameter. The preoperative differential diagnoses were adenoma of the minor duodenal papilla or duodenal adenoma, and we therefore proceeded with endoscopic mucosal resection. Histopathological examination of the resected specimen revealed well-differentiated Adenocarcinoma in adenoma of the minor duodenal papilla. This patient remained free of recurrence for 20 months. Primary adenocarcinoma of minor duodenal papilla is extremely rare. This is the first description of primary adenocarcinoma of the minor duodenal papilla treated by endoscopic mucosal resection.

An 89-year-old woman with abdominal pain and vomiting was admitted to our hospital. Abdominal computed tomography showed food-induced ileus caused by a plum species that the patient had eaten. Although an ileus tube was inserted, the ileus did not improve and the food residue remained in the bowel. Using double balloon enteroscopy (DBE), the food residue was found in the stenotic small intestine and removed. The patient was discharged from the hospital without complications. Using DBE combined with an ileus tube has been reported as the “triple-balloon method”. The “triple-balloon method” was useful for treating food-induced ileus.

Anal canal cancer is rarely diagnosed, although colon cancer is more and more frequently diagnosed, and most anal canal cancers are diagnosed at an advanced stage. As to treatment, in Europe and the United States chemoradiation therapy is the standard treatment for adenocarcinoma and squamous cell carcinoma (SCC) ; however, there is no systematic standard therapy for SCC. It was reported that magnifying endoscopy with narrow band imaging is beneficial for diagnosing SCC at an early stage, and if the cancer is diagnosed at an early stage, it may be treated by endoscopic submucosal dissection (ESD) as SCC is an early cancer. In our patient, we diagnosed SCC of the anal canal at an early stage by using narrow band imaging and treated it with ESD.

Pathological examination showed the resected specimen to be SCC in situ. The horizontal and vertical margins were free of tumor, and there was no lymphovascular invasion.

It is thought that narrow band imaging is useful for diagnosis of the invasion depth of SCC of the anal canal, and ESD can be an option for therapy if the lesion is diagnosed as early cancer.

A 45-year-old man with advanced pancreatic ductal adenocarcinoma received conventional chemotherapy. During chemotherapy, he developed obstructive jaundice due to malignant obstruction of the distal bile duct and a covered self-expandable metallic biliary stent (SEMS) was placed. One month later, he suffered hemorrhagic shock with bloody stool. Gastroduodenoscopy revealed bleeding from a site close to the papilla of Vater along the metallic stent. Abdominal angiography revealed rupture of the posterior superior pancreaticoduodenal artery by tumor invasion. Hemostasis of the posterior superior pancreaticoduodenal artery was achieved via transcatheter arterial embolization using n-butyl-2-cyanoacrylate. Our patient developed hemobilia from the ruptured vessel in the bile duct due to tumor invasion, even though the bleeding point had been compressed with SEMS. This case was very rare, but it is necessary to keep in mind that fatal hemobilia caused by tumor invasion is a possible complication of SEMS placement.

Approximately 60% of all superficial esophageal cancers are type 0-Ⅱc lesions, which have varying invasion depths ranging from T1a-EP to T1b-SM. For type 0-Ⅱc lesions, evaluation of the depth of tumor invasion is essential. The first step in determining the depth of invasion is to predict the approximate depth based on routine assessment of lesion morphology, mobility, and other observable features. When an invasion depth of T1a-MM or more is suspected, magnifying endoscopy or endoscopic ultrasound (EUS) is performed to examine the site with marked irregularities of the surface to predict the depth, size and mode of invasion at the deepest point. This approach may not work for cases with microscopic tumor invasion. However, EUS is effective when it is difficult to determine the depth of invasion based on vascular changes, such as lesions showing differences in findings between routine assessment and magnifying endoscopy, lesions with thickening of the depressed area, and type R lesions. Magnifying endoscopy and EUS each have limitations if used alone. Therefore, it is important to examine all findings in a comprehensive manner to ensure diagnostic accuracy.

Walled-off necrosis is a serious late complication of severe acute pancreatitis and requires drainage in symptomatic cases presenting with infection. Recently, endoscopic ultrasound (EUS)-guided transluminal drainage and direct endoscopic necrosectomy have yielded a good treatment outcome for walled-off necrosis. 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 of walled-off necrosis with endoscopic treatment alone. However, without being restricted to endoscopic treatments, a wide range of options including surgery should be considered as treatments for walled-off necrosis.

Helicobacter pylori (H. pylori) leads to chronic gastritis and eventually causes gastric cancer. The prevalence of H. pylori infection is gradually decreasing with improvement of living conditions and eradication therapy. However, some reports have described cases of H. pylori-negative gastric cancers (HpNGC), and the prevalence was 0.42-5.4％ of all gastric cancers. Diagnostic criteria of HpNGC vary among the different reports ; thus, they have not yet been definitively established. We recommend negative findings in two or more methods that include endoscopic or pathological findings or serum pepsinogen test, and negative urease breath test or serum immunoglobulin G test and no eradication history the minimum criteria for diagnosis of HpNGC. The etiology of gastric cancers, excluding H. pylori infection, is known to be associated with several factors including lifestyle, viral infection, autoimmune disorder and germline mutations, but the main causal factor of HpNGC is still unclear. Regarding the characteristics of HpNGC, the undifferentiated type (UD-type) is more frequent than the differentiated type (D-type). The UD-type is mainly signet ring-cell carcinoma that presents as a discolored lesion in the lower or middle part of the stomach in relatively young patients. The gross type is flat or depressed. The D-type is mainly gastric adenocarcinoma of the fundic gland type that presents as a submucosal tumor-like or flat or depressed lesion in the middle and upper part of the stomach in relatively older patients. Early detection of HpNGC enables minimally invasive treatment which preserves the patient’s quality of life. Endoscopists should fully understand the characteristics and endoscopic findings of HpNGC.