Primary malignant lymphomas of the gastrointestinal tract account for 30-40% of all extranodal lymphomas, and the gastrointestinal tract is the second most common organ of origin for lymphoma, after the lymph nodes. As the clinical course, including prognosis and treatment options, of gastrointestinal malignant lymphoma differs depending on the histological type and clinical stage, accurate histopathological and staging diagnosis is required. Furthermore, there are various histologic types and endoscopic findings which can correspond to the same pathologic type to some extent. Therefore, an accurate histopathologic diagnosis can only be made through understanding the basic developmental pattern of gastrointestinal malignant lymphoma and the characteristic endoscopic findings of each histologic type. This article outlines the essential characteristics of endoscopic diagnosis of gastrointestinal malignant lymphoma, with the presentation of representative endoscopic findings.

A 76-year-old man who presented with dysphagia was admitted to our hospital for management of esophagogastric junction cancer and underwent subtotal esophagectomy with gastric tube reconstruction. Endoscopic and video-fluoroscopic evaluation performed on the 7th postoperative day revealed complete obstruction of the esophagogastric anastomosis, which was attributed to an esophageal mucosal pinch injury during anastomosis. We attempted endoscopic recanalization of the obstructed anastomosis (rendezvous endoscopy) from both the oral and gastric ends. We accessed the gastric end by opening the surgical wound and nicking the gastric tube under general anesthesia. Both the oral and gastric endoscopes could detect the contralateral endoscopic light through the obstructed esophageal mucosa. Using the Hook knife-J, we safely punctured along the appropriate direction of the esophageal mucosa. After incising the obstructed segment, a guidewire was inserted to perform balloon catheter dilation without any adverse events. A literature search revealed that this report is the first to describe rendezvous endoscopic recanalization for management of complete obstruction of the esophagogastric anastomosis after subtotal esophagectomy. Rendezvous endoscopic intervention may avoid surgical reanastomosis in cases of complete esophageal obstruction.

A 52-year-old man who underwent stapled hemorrhoidopexy for internal hemorrhoids 15 years ago, visited our hospital for evaluation of anorectal discomfort and dyschezia. Colonoscopy revealed a submucosal tumor on the dorsal aspect of the rectum. His symptoms were attributed to the submucosal lesion, and we performed endoscopic unroofing. Intraoperatively, we detected a cyst-like structure containing a spherical foreign body under the mucosa, and the foreign body was removed. The patientʼs symptoms disappeared rapidly after endoscopic treatment. The tumor was histopathologically diagnosed as a pararectal cyst containing a spherical foreign body. Owing to its minimal invasiveness, we recommend endoscopic unroofing as a useful therapeutic option for symptomatic pararectal cysts.

An 87-year-old woman with a history of biliary stenting for common bile duct stones 13 years prior to presentation was admitted for evaluation of lower abdominal pain and gastrointestinal bleeding. Contrast-enhanced computed tomography revealed a stent-stone complex (SCC) in the bile duct; however, no extravascular leakage was detected. Esophagogastroduodenoscopy revealed a choledocho-duodenal fistula with insidious bleeding from the fistula. Abdominal angiography performed for evaluation of recurrent gastrointestinal bleeding revealed a right hepatic artery aneurysm with extravascular leakage from the aneurysm into the common hepatic duct, and transcatheter arterial coil embolization achieved effective hemostasis. Aneurysm formation was attributed to mechanical stimulation secondary to the SCC, with the stent (implanted 13 years prior) forming its core and recurrent cholangitis-induced inflammation.

A 64-year-old woman who received chemotherapy for unresectable pancreatic head cancer with multiple liver metastases developed a pancreatic fistula after uncovered self-expandable metallic stent (SEMS) insertion for management of distal malignant biliary obstruction. Owing to SEMS placement, we could not perform successful endoscopic transpapillary pancreatic duct drainage. Endoscopic ultrasound-guided pancreatic duct drainage facilitated adequate dilation of the main pancreatic duct. However, walled-off necrosis (WON) spread to the iliopsoas and tailorʼs muscles with concomitant infection. Therefore, we performed percutaneous endoscopic necrosectomy (PEN) using a small-diameter endoscope in addition to percutaneous drainage to treat the WON. This case report highlights the usefulness of percutaneous drainage and PEN as alternative combination treatment for surgical drainage in cases of extensive WON.

Sedation in endoscopy and treatment is becoming increasingly necessary for the purposes of reducing patient distress and ensuring safe treatment. In Japan, benzodiazepines are frequently used as sedative agents and the second edition of the Guidelines for Sedation in Endoscopic Practice (published in 2017) now includes a clear statement regarding the usefulness of propofol in endoscopy and treatment and the possibility of propofol use by gastrointestinal endoscopists. However, use of propofol in endoscopic practice and treatment remains limited due to insurance coverage issues and safety concerns. Therefore, it is desirable to accumulate more cases so that endoscopists can safely and accurately sedate patients with propofol, and subsequently establish an educational system for sedation.

Endoscopic sleeve gastroplasty (ESG) is a newly developed endoscopic bariatric surgery in which the stomach is sewn in full-thickness layers using an endoscopic suturing device to reduce stomach volume. ESG not only achieves a higher weight loss effect, but also has lower invasiveness and complication rates. Recently, ESG has become widespread (mainly in Europe and the United States) as a less invasive new treatment method for obesity. Although the number of obese patients is lower in Japan than in Europe or the United States, Asians tend to develop metabolic syndrome though their absolute BMIs may be low. Therefore, it is expected that ESG will become commonplace and prevalent in Japan as a new treatment option for patients with mild obesity who are not indicated for bariatric surgery or patients who are reluctant to receive surgery.

Objectives: Although many patients with early gastric cancers (EGCs) die of non-gastric cancer-related causes, the association of the risk categories of lymph node metastasis (LNM) with all-cause mortality remains unclear. We aimed to clarify the predictors of early and late mortality, separately.

Methods: Patients with endoscopic resection or gastrectomy for EGCs between 2003 and 2017 were retrospectively enrolled. We analyzed predictors for early and late mortality, including risk categories of LNM, treatment method, and nine non-cancer-related indices, separately, with a cut-off value of 3 years.

Results: We enrolled 1439 patients with a median follow-up period of 79 months. The 5-year overall survival rate was 86.8%. In the multivariate Cox analysis, the most important predictors for early and late mortality were age ≥85 years (hazard ratio [HR] 2.88 and 4.54, respectively) and Eastern Cooperative Oncology Group Performance Status ≥2 (HR 3.00 and 4.19, respectively). Charlson comorbidity index ≥2 (HR 2.76 and 1.99, respectively), American Society of Anesthesiologists Physical Status ≥3 (HR 2.35 and 1.79, respectively), and C-reactive protein/albumin ratio ≥0.028 (HR 2.30 and 1.58, respectively) were also predictors for both early and late mortality. Male (HR 2.26), intermediate- (HR 2.12)/high-risk (HR 1.85) of LNM in eCura system, and sarcopenia evaluated by the psoas muscle mass index (HR 1.70) were predictors for early mortality.

Conclusion: The combined assessment of multiple predictors might help to predict early and/or late mortality in patients with EGCs. The eCura system was associated with early mortality

The “Study Group on the Establishment of Diagnostic Criteria for Type A Gastritis” of the Japan Gastroenterological Endoscopy Society has proposed new diagnostic criteria for autoimmune gastritis (AIG; type A gastritis).

The diagnostic criteria are: “either endoscopic or histological findings, or both, meet the requirements for AIG, and are positive for gastric autoantibodies (anti-parietal cell antibodies or anti-intrinsic factor antibodies, or both).”

AIG has been underdiagnosed in the past. The newly proposed diagnostic criteria will allow more frequent and early diagnosis of AIG. It would allow patients to be stratified into various high-risk groups, such as gastric tumors and pernicious anemia. With new diagnostic criteria, it would be possible to establish an appropriate surveillance system in the future. There are still issues to be addressed, like establishing endoscopic findings for early-stage AIG and obtaining insurance coverage for gastric autoantibodies.