Between April 2008 and March 2016, 256 lesions diagnosed as gastric cancer within 2.5 years after screening endoscopy were studied retrospectively. Invasion depth of M/SM1/SM2-3/MP/SS was seen in 193/27/27/6/3 lesions. The 36 gastric cancers invading SM2 and deeper were detected more frequently in the cardia, upper body and middle body than in other areas, especially in the lesser curvature of the cardia and posterior wall of the upper to middle body. These 36 lesions were divided into three groups according to the previous endoscopic findings. The 16 lesions (44%) in the rapidly increasing group could not be diagnosed as cancer on previous screening endoscopy. However, the 9 lesions (25%) in the insufficient observation group and 11 lesions (31%) in the suspicious cancer group could have been detected on previous endoscopy. The quality of endoscopic examinations will improve through evaluation of gastric cancers detected after screening endoscopy.

To reduce the occurrence of colonic perforation by colonic self-expandable metallic stenting, we analyzed our experience. A retrospective review was conducted of 27 consecutive patients who underwent stenting at our center from June 2016.

Twenty-four cases of stenosis were caused by colorectal cancer, and resection of the primary tumor was performed after stenting in 17 of the 24 cases. All stents were 22mm in diameter and consisted of Niti-S and HANAROSTENT. Stenting improved "ColoRectal Obstruction Scoring System (CROSS) " score in 25 of the 26 cases (96%). In one case, it did not improve because hard stools were stacked. No stent migrated.

Perforation occurred in 3 cases (11%). One case suggested that stenting over the normal rectum may not be preferable in patients with sigmoid colon stenosis. Another case suggested that the possibility of perforation should always be kept in mind especially in peritoneal carcinomatosis patients. The third case suggested that a long period of obstruction before stenting may lead to perforation.

The preventive effects of endoscopic hemostasis for rebleeding of colonic diverticular hemorrhage (CDH) remain controversial. We retrospectively evaluated the risk factors for rebleeding after endoscopic hemostasis for CDH. This study included 146 patients treated with endoscopic hemostasis for CDH from April 2013 to December 2017. We initially achieved endoscopic hemostasis in all patients without any severe complications. Of 146 patients, early rebleeding (i.e. rebleeding within 30 days after initial hemostasis) occurred in 27 patients and late rebleeding occurred in 37 patients. The risk factor for early rebleeding was hemostasis by non-ligation method (odds ratio: 3.62; 95% CI: 1.13-15.22; P=0.025) according to the multivariate analysis. Risk factors for late rebleeding were history of diverticular hemorrhage (odds ratio: 3.36; 95% CI: 1.32-8.51; P=0.011) and ischemic heart disease (odds ratio: 9.76; 95% CI: 3.28-29.00; P<0.001). These findings suggest endoscopic hemostasis might not be able to prevent late rebleeding. The ligation method could be a first-line treatment for CDH.

Endoscopic diagnosis for identifying early cancer in small colon polyps is essential to select appropriate endoscopic resection method. This study aims to assess the clinical usefulness of NBI magnifying endoscopy for diagnosis of early cancer in colorectal lesions <10mm. We retrospectively analyzed all colorectal lesions <10mm which were diagnosed by NBI magnifying endoscopy according to The Japan Narrow-band imaging Expert Team (JNET) classification and resected endoscopically from March 2014 to September 2016. 797 lesions in 394 patients were analyzed. Pathologically, 696 (87.2%) lesions were adenoma, 10 (1.3%) and 2 (0.2%) lesions were Tis and T1 cancer, respectively, counting 1.5% cancer-carrying rate. 753 lesions diagnosed as JNET Type2A harbored only 4 cancers (0.5%). In sharp contrast, 12 lesions diagnosed as JNET Type2B comprised 7 cancers (58.3%) and one lesion diagnosed as JNET Type3 was T1b cancer, which indicates Type2B/3 are reliable findings for diagnosis of early cancer. NBI magnifying endoscopy according to JNET classification is a useful modality for diagnosis of early cancer in colorectal lesions <10mm.

Hybrid endoscopic submucosal dissection (H-ESD) is an endoscopic mucosal resection technique that uses a snare after circumferential incision and partial submucosal dissection. This procedure shortens the procedure time but increases the risk of piecemeal resection owing to snare resection. Although acceptable for endoscopic treatment of colorectal tumors, it is not commonly used to treat gastric tumors. The endoscopic knife specifically designed for H-ESD combines a needle-type tip and a snare within a single device. This device is available in Japan, and we recently performed H-ESD for a gastric tumor using this device. Indications of H-ESD for gastric tumors used at our hospital are: 1) tumor size <10mm, 2) absence of ulcerative findings, 3) cT1a stage disease and, 4) differentiated tumors based on histopathological examination. We report the indications, devices, and technical details of H-ESD for gastric tumors.

Peroral cholangioscopy is a useful examination method, as it enables direct observation of the lesion and biopsy. Our hospital introduced SpyGlass DS (Boston Scientific), a new peroral cholangioscope in 2016. We report our experience with 14 cases wherein SpyGlass DS was used for diagnostic and therapeutic purposes between September 2016 and January 2018, retrospectively. The objectives were diagnostic in 8 cases, therapeutic in 3 cases of bile duct stone, and 3 cases of confirmation of bile duct calculus. Bilious intubation with the Spyglass DS was possible in all the cases. The median procedure time was 45.5 minutes, and the clinical success rate was 92.2%. Papilla hemorrhage occurred in one patient but was reduced with clipping and hypertonic saline-epinephrine injection. We intend to continue gathering cases and studying treatment outcomes, complications and more.

The rate of local recurrence after chemoradiotherapy (CRT) remains high despite its demonstrated utility in the treatment of esophageal cancer. Surgical and endoscopic interventions are performed for treatment for local recurrent lesions after CRT; however, surgical approaches were reported to be associated with high postoperative mortality rates. Recent studies reported the utility of endoscopic submucosal dissection (ESD) for locally recurrent lesions after CRT. We herein report the case of a 77-year-old man diagnosed with stage II esophageal squamous cell carcinoma. Although the patient achieved complete response by CRT, local recurrence was observed 7 years and 6 months later. Complete resection was achieved by ESD without any adverse events. There was no recurrence at one year after the ESD.

The criteria for curative resection after endoscopic resection of gastric cancer were recently revised in the Japanese Gastric Cancer Association's Japanese Gastric Cancer Treatment Guidelines 2014 (version 4). Mixed-type (predominantly differentiated-type) early gastric cancer smaller than 3cm in diameter, ulcer positive, and pT1a invasion depth is now indicated for endoscopic resection with curative intent. Consequently, making an accurate preoperative diagnosis of the pathological type has now become even more important. Since making a diagnosis on the basis of biopsy specimens is not always accurate for mixed-type early gastric cancer, diagnosing the pathological type using narrow-band imaging with magnifying endoscopy (NBI-ME) is useful.

A 68-year-old man underwent esophagogastroduodenoscopy for medical checkup. A depressed lesion with fold convergence was detected at the posterior side of the middle gastric body. Biopsy was obtained, and mixed early gastric cancer was suspected. Mixed-type (predominantly differentiated-type) early gastric cancer was accurately diagnosed by NBI-ME prior to the operation; therefore, it was successfully treated by curative resection with endoscopic submucosal dissection.

Although the efficacy of long-term indwelling endoscopic gallbladder stent (EGBS) has been established in recent years, we report here a case of gallstone ileus that developed under the presence of indwelling EGBS. An 84-year-old female visited her local clinic due to right abdominal pain that had lasted for 3 days. Ultrasonography revealed a gallbladder stone and the gallbladder swelling. Accordingly, she was referred to our hospital, where we detected a 5-cm stone impacted in the gallbladder neck on imaging, and we admitted the patient with a diagnosis of acute cholecystitis. As it was difficult to secure a puncture route for percutaneous transhepatic gallbladder drainage we performed endoscopic retrograde cholangiopancreatography to place EGBS through the papilla. The patient progressed favorably after the procedure and was discharged on hospital day 10. Although the patient was followed up without cholecystectomy, 3 months later, she was transported to the hospital by ambulance with abdominal pain and vomiting. A CT scan revealed that the gallbladder stent had fallen into the ileocecal region and a gallstone was impacted in the ileum, causing gallstone ileus. After admission, we initiated treatment by placing an ileus tube and removed the gallstone by ileotomy after the ileus improved. The patient progressed well postoperatively and was discharged on hospital day 42 of the second hospitalization.

We presented a case of 75 years-old patient with esophageal cancer who underwent the ESD. He had a history of a permanent pacemaker due to sick sinus syndrome. It was said that the remarkable progress in permanent pacemaker made high frequency current decreased, but malfunction of it could affect the patient's life. As it had been said than before, it was necessary to keep a distance between the position of the electrocautery scalpel and the return electrode plate as much as possible. In our case, the distance between the permanent pacemaker and the electrocautery was very close because the treatment site was the esophagus. Therefore, I requested the pacemaker suppliers to change the mode of the permanent pacemaker (DDD → DDI) and then operated the esophageal ESD. We could accomplish safely without malfunction.

Since lymph node metastases are rare in early esophageal cancer diagnosed as T1a-EP or T1a-LPM, endoscopic resection (ER) has become the standard treatment for these early esophageal cancers. However, a high level of skill is required for ER of extensive and circumferential lesions, and the risk for postoperative stenosis should also be considered. We herein report a 70-year-old female with wide-spreading superficial esophageal cancer. Superficial esophageal cancer of more than 5cm in size was found in the thoracic esophagus, and argon plasma coagulation (APC) was performed. No signs of recurrence were found at one year after APC. Further follow-up for recurrence is necessary because histological evaluation is not possible in patients who are treated with APC.

A male in his fifties who had been diagnosed as adenocarcinoma of esophagogastric junction by screening endoscopy. Esophagoscopy revealed a 15mm- slightly elevated lesion (Paris type 0-IIa) locating on the left wall of the esophagogastric junction. ESD was performed as a purpose of total biopsy. The final pathological diagnosis was Barrett's esophageal cancer, with deep submucosal invasion. It is consistent with that the tumor arose from Barrett's epithelium, since non-neoplastic glandular epithelium with intestinal metaplasia was found adjacent to the tumor. ESD enables secure resection and precise pathological diagnosis, thus contributes to decide indication of surgery for patients with Barrett's adenocarcinoma.

The patient was a 64-year-old male as a habitual drinker (ethanol amount: 60-80g/day) who visited us for possible chronic pancreatitis in health examination. In abdominal CT findings, we found 3 pancreatic stones in main pancreatic duct of pancreas head and main pancreatic duct dilatation, so we diagnosed it as alcoholic chronic pancreatitis. With ERCP, we could perform the partial removal with 4-wire basket catheter after EPST, but it was still difficult to remove other stones. After two session of ESWL, we successfully removed other stones using grasping forceps (FG-8U-1, Olympus Co.) under fluoroscopic guidance. The abdominal CT findings showed no residual stone after 2 months. The endoscopic lithotomy for pancreatic stone was very difficult in some cases. However removal technique using grasping forceps is useful for some difficult cases.

A 70-year-old man who presented epigastralgia and hematemesis just after dinner was admitted to our hospital. He had been taking warfarin for atrial fibrillation, and two months before he had started to take clopidogrel and aspirin for prevention of coronary stent thrombosis. Computed tomography of the chest showed thickening of the upper and lower parts of the esophagus. Because he presented no hematemesis in fair general condition, he was treated with conservative therapy without any anticoagulants. However, esophagogastroduodenoscopy (EGD) revealed near-circumferential intramural esophageal hematoma without active bleeding on the next day. Four days later, the follow-up EGD indicated that the hematoma shrunk slightly, therefore heparin therapy was started. Without any adverse events, soon he resumed oral intake. After the 3rd EGD, heparin was switched to edoxaban and clopidogrel was added thereafter. He was discharged on the 23rd hospital day.

A 60-years-old man was refferd to our hospital with elevation of hepatobiliary enzymes. The elevation of tumor markers was found. Abdominal contrast enhanced CT showed complete visceral inversion and tumorous lesion in the upper bile duct. ERCP findings showed the stricture of upper bile duct. Peroral cholangioscopy showed tumor extension from the central bile duct to the right hepatic duct. Cytology of the biliary stenosis was class V and diagnosised as cholangiocarcinoma. Because of the complete visceral inversion, the patient requested a surgery at a more specialized facility. Thus, right hepatectomy and caudate lobectomy and extrahepatic bile duct resection was performed. Histopathological finding was moderately differentiated tubular adenocarcinoma pT2aN1M0 stage IIIb.

A 65-year-old male was diagnosed with type 0-IIa early gastric cancer of the lesser curvature of the gastric antrum by his previous physician based on an upper gastrointestinal endoscopic examination. The patient was referred to our hospital for treatment, and endoscopic submucosal dissection (ESD) was performed. The histopathological findings showed well-differentiated adenocarcinoma and depth of invasion was limited into the mucosal layer. No vascular invasion or lymphatic invasion was seen, and the resection had been curative. Because there was severe cell atypia and tumor cells with clear cytoplasm were conspicuous, α-fetoprotein (AFP) and glypican-3 staining was performed. The results showed that some of the cells were positive, and we made a diagnosis of AFP-producing gastric cancer. Because AFP-producing gastric cancers are known to be highly malignant, whenever AFP-producing gastric cancer is suspected based on the macroscopic or pathological findings, diagnosis by immunostaining should be proactively taken into consideration.

A 70-year-old male had undergone esophagogastroduodenoscopy (EGD) every year for evaluation of chronic gastritis since 2007. Endoscopy showed an area of discoloration with submucosal tumor-like shape, measuring 10mm on the anterior wall in the upper portion of the stomach. It exhibited dilated superficial vessels with branching architecture. Biopsy had been performed several times, but there was no evidence of malignancy. In 2015, EGD and biopsy were performed again. From pathological examination, gastric adenocarcinoma of the fundic gland type was suspected. We performed endoscopic submucosal dissection and achieved complete resection. The final pathological diagnosis was gastric adenocarcinoma of fundic gland mucosa type. The shape and diameter of the lesion had not significantly changed over the eight-year period. Here we report a rare case of gastric adenocarcinoma of the fundic gland mucosa type that showed very slow progression.

A 64-year-old woman visited our hospital because of inappetence, stomachache and vomiting. Esophagogastroduodenoscopy revealed advanced gastric cancer with antral stenosis. We placed a metallic stent at the stenotic region, and the patient received chemotherapy. After 8 courses of chemotherapy, the patient developed abdominal pain and vomiting. Computed tomography (CT) revealed that the small bowel was obstructed with the migrated metallic stent. CT performed three days later revealed that the stent had moved to the splenic flexure, and the ileus was improved. The stent could not be removed with the colonoscope. Since the patient was stable, we restarted chemotherapy.

The stent remained in the splenic flexure, and we continued to administer chemotherapy for five months, when the patient died of pneumonia. Early detection of migrated stent is important for successful treatment. Periodic imaging examination is necessary for patients with a gastrointestinal metallic stent.

A 53-year-old male visited a clinic nearby for positive fecal blood test and got upper and lower gastrointestinal (GI) endoscopy. The upper one revealed a lesion in stomach and he was introduced to our hospital. A discolored and slightly depressed lesion on the front wall of the gastric antrum was observed by upper GI endoscopy and diagnosed as amyloidosis of AL type by histological examinations of the biopsy samples. Most cases of AL amyloidosis are secondary and systemic and systemic examinations were performed. No lesion except for the stomach was pointed out and the patient was diagnosed as localized gastric amyloidosis. The prognosis of localized amyloidosis in stomach is much better than systemic one and the treatments are quite different, so that a systemic search for amyloidosis is very important when amyloidosis is proved by stomach biopsy.

Two cases in which fistula closure was attempted using a Funada-style gastropexy device for intractable fistula perfusion are reported. Case 1 was a 99-year-old woman, and case 2 was an 86-year-old man. Both cases had severe inflammation around the fistula after gastrostomy. Since closure was not performed after removing the gastrostomy, the fistula was closed using a Funada-style gastropexy device. Fistula closure using a Funada-style gastropexy device was considered effective for treating fistula insufficiency, because it can suture both the stomach wall and the skin. As a future task, one must consider the interval until stitching.

A 78-year-old woman with vascular Parkinson syndrome who had an indwelling bumper-button type percutaneous endoscopic gastrostomy (PEG) catheter was transported to our hospital after accidental removal of the PEG catheter. Gastrointestinal endoscopy showed that the bumper remained in the antrum. The PEG catheter was replaced and the remaining bumper was removed. She was discharged on day 5. In this patient, similar event occurred two years previously and also four months later. As counter measures against accidental removal of the PEG catheter occurring three times in a short period from the previous exchange not accompanied by aged deterioration, we thought about a gastric inhibitor, caregiver education, and shortening the interval of PEG exchange.

A 70-year-old woman presented to our hospital with diarrhea. Although colonoscopy was normal, gastroscopy revealed a centrally depressed protruding lesion in the second portion of the duodenum. Biopsy showed a tubular adenocarcinoma, leading to a diagnosis of duodenal carcinoma. Secondary to liver metastasis, she underwent chemotherapy with 26 courses of 5-fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6), 4 of modified irinotecan and infusional 5-fluorouracil, and 4 of weekly paclitaxel administration. During mFOLFOX6 administration, endoscopy revealed complete remission of the duodenal lesion, and a biopsy specimen tested negative for malignancy. She survived over 29 weeks after the initial diagnosis.

We report successfully using optimal chemotherapy to treat a patient with duodenal carcinoma. Whether duodenal cancer shares biological characteristics with stomach or colon cancer remains controversial; however, establishing optimal regimens is warranted, and our report would support this research.

A 74-year-old male patient was admitted to our hospital with a diagnosis of ulcer in the upper gastrointestinal tract. Upper gastrointestinal endoscopy revealed a bleeding ulcer on the posterior wall of the duodenum, from which massive bleeding occurred during the examination. Because hemostasis could not be achieved by endoscopic procedures, we attempted an emergency transcatheter embolization. However, complete hemostasis could not be achieved, and the patient underwent emergency surgery. After laparotomy, the patient suffered cardiac arrest. We were able to achieve hemostasis by directly suturing the gastroduodenal artery which was exposed at the ulcer base, while resuscitating the patient by cardiac compression and massive blood transfusion. Wound closure was performed later in a two-step manner. He was discharged without delayed neurological complications on day 118 after the surgery.

A 69-year-old man presented to our hospital with the chief complaints of vomiting and right hypochondrium pain. Upper gastrointestinal endoscopy showed a stage-A2 ulcer on the expanded pyloric ring and a funnel-shaped stenosis adjacent to the ulcer. The stenosis extended from the lesser curvature of the duodenum to the anal part of the duodenum. The papilla of Vater existed adjacent to the stenosis. The bulb and the proximal descending limb of the duodenum were markedly extended like a pouch. Because the bile duct, pancreas, pancreatic duct, and colon were normal on radiological studies, congenital duodenal stenosis was suspected. We assumed that there was duodenal stenosis on the anal side of the papilla of Vater and that shortening of the duodenum was caused by recurrent peptic ulcer and stagnation of stomach and duodenal contents due to stenosis.

A 66 year-old man with palpitation was referred to our hospital for the evaluation. We diagnosed a duodenal ulcerous lesion as the cause of his anemia through esophagogastroduodenoscopy. However, administration of one-month potassium-competitive acid blocker was not fully effective. The healing of ulcer lesion delayed and little regenerating epithelium was observed. Anemia and gastrointestinal bleeding recurred repeatedly. Then, we performed angiography and found that abnormal network of blood vessels in uncinate process of the pancreas and early visualization of portal vein. We diagnosed pancreatic arteriovenous malformation (PAVM) as the cause of his ulcerous lesion in this case. We performed transcatheter arterial embolization. Fortunately, anemia and gastrointestinal bleeding have not recurred for 6 months.

A 47-year-old female with a history of bipolar disorder was admitted to our hospital with diarrhea. Several hours after admission, she presented hematemesis. Upper endoscopy revealed hemorrhagic mucosal injury in the upper gastrointestinal tract. Furthermore, capsule endoscopy showed multiple ulcers in the small intestine. She reported being prescribed loxoprofen 360mg daily for the 4 months prior for headache. The nonsteroidal anti-inflammatory drug therapy was discontinued, and she was treated with an intravenous proton-pump inhibitor (PPI). She had also disseminated intravascular coagulation (DIC) associated with sepsis. The improvement of DIC was obtained with intravenous broad spectrum antibiotics. The mucosal injury in the upper gastrointestinal tract promptly improved, but it took more time for the multiple ulcers in the small intestine to improve.

A 59-year-old female presented to the gastroenterology clinic of our hospital after passing proglottids in her stool. Capsule endoscopy revealed a white cestode in the small intestine. Amidotrizoic acid was administered through a duodenal tube, and the tapeworm was expelled about 10 minutes later. The tapeworm was subsequently identified as Taenia asiatica by DNA sequencing.

With the number of foreign visitors to Japan continuing to increase, the number of patients with gastrointestinal parasitic diseases encountered in daily clinical practice is also expected to increase. Capsule endoscopy is effective in diagnosing gastrointestinal parasitic diseases. Also, subsequent identification of expelled tapeworms will allow for the monitoring of imported infectious diseases and emerging infectious diseases.

A 79-year-old man with a history of four surgeries for colorectal cancer, intestinal obstruction, stomach cancer, and choledocholithiasis underwent a fifth surgery for recurrent intestinal obstruction. Surgery consisted of partial resection of the small intestine segment containing the site of obstruction and reconstruction with end-to-end anastomosis. After surgery, a drain was placed for intraabdominal abscess caused by ruptured suture in the cecum on the anal side. Subsequently, dilatation developed and expanded from the small intestine near the abscess site presumably because of the development of stricture due to inflammation. Decompression by using an ileus tube did not improve the patient's condition, but to avoid a difficult surgery due to severe adhesions, we performed balloon dilation using single-balloon enteroscopy, which successfully improved the intestinal obstruction. The patient has been well with no sign of stricture for the past 1 year as of this writing.

A 79-year-old woman presented with constipation and underwent polypectomy in 2009. She underwent colonoscopy annually thereafter. Pus, edema, and redness around diverticuli were observed in her sigmoid colon in 2012. Recurrence of ulcerations and scarring in her left-side colon was observed in 2014. Although her symptoms had not worsened, her sigmoid colon was strictured and she underwent left hemicolectomy in 2015. Histopathological examination revealed transmural deep fissures with non-specific inflammatory cell infiltration around them. No granuloma was detected. Relapse of colitis has not been seen since then. From her course, histopathological findings and endoscopic findings, diverticular colitis was diagnosed. Diverticular colitis is a non-specific chronic mucosal inflammation in a colonic segment with diverticuli. She has been taking aspirin for her comorbid heart disease and had a past history of polysurgery, which may have aggravated her disease course.

This report presents a case of intestinal obstruction linked to pseudo enterolith in postoperative colon loop.

A 84-years-old female presented with subabdominal pain, and admitted to our hospital under adiagnosis of intestinal obstruction. X-ray examination revealed a gas image from the colon to the small intestine and niveau. Computed tomography showed that a spherical body were present in the lumen of sigmoidal colon. It was approximately 40mm, and calcified. We diagnosed that the spherical body is enterolith, and cause of the intestinal obstruction. Enterolith lithotripsy performed 4times with an endoscope. After lithotripsy, barium enema revealed colon loop, anastomosis of sigmoidal colon and transverse colon. We presume that enterolith formed in this postoperative colon loop.

The patient was an 84-year-old man who had undergone total cystectomy and Indiana pouch construction for bladder cancer in 1989. At the previous hospital in 2017, he was diagnosed with urinary tract infection due to a fever. Abdominal computed tomography showed elevated lesion in the pouch, and the patient was subsequently referred to our hospital. Under cystoscopy, biopsy from the tumor was adenocarcinoma. A scope inserted through the stoma revealed a 15mm 0-Is polyp in the pouch, and endoscopic mucosal resection (EMR) was performed. Histopathological findings were submucosal invasive cancer (tub2, pT1b, ly0, v0, budding grade1, pHMX, pVMX). Considering the patient's age, complications, and performance status, course observation was selected without additional resection despite being at high-risk on histopathological examination after EMR. A second cystoscopy using colonoscope performed 5 months after EMR showed no recurrence.

A 79-year-old man was referred to our hospital for further examination of a colorectal cancer. Colonoendoscopy revealed a 0-Is type lesion of 18mm in diameter in the rectosigmoid colon, showing redness on conventional images. In magnified images, the lesion showed JNET type 3 findings on narrow band imaging (NBI) and a VI high-grade pit pattern on chromoendoscopy after crystal violet staining. We diagnosed the lesion as submucosal massively invasive cancer and surgical resection with D2 lymph node dissection was performed. Histological examination revealed well to moderately differentiated tubular adenocarcinoma with invasion into veins of the subserosa. Although advanced colorectal cancers of less than 20mm in diameter are relatively rare, we should keep in mind the difficulty of diagnosis of depth invasion of such protruded cancers.

An 81-year-old male with chronic obstructive pulmonary disease history received colonoscopy for anemia in February 2016, which detected advanced cecal cancer. Considering surgery high risk because of his comorbidity, the best supportive care was selected. One and a half years later, a colonic stent was placed in the ileocecum for intestinal obstruction. However, he frequently defecated and reported strong abdominal pain next month. Abdominal X-ray and CT revealed stent migration into the descending colon. Urgently, colonoscopy was performed, and the stent was successfully removed by pulling its oral side, reversing it inside out with two grasping forceps using a double-channel endoscope, and drawing it into the sliding tube to prevent injuring anus. When stents migrate and endoscopic withdrawal is feasible, patients' physical burden is minimal. Hence, endoscopists should familiarize with endoscopic removal method upon stent migration.

Breast cancer may spread to lung, bone, liver and brain but metastasis of intestine is rare. We experienced a case of large intestine metastasis of breast cancer as submucosal tumor. As for this case, endoscopic findings, and pathological features are discussed here.

A 77-year-old woman was admitted to our hospital with a complaint of abdominal pain. The image examination confirmed sigmoid volvulus. We performed endoscopic detorsion. A few days later, she developed abdominal pain again. We performed contrast computed tomography (CT) scan, which showed the inferior mesenteric veins thrombosis. After the diagnosis, heparin was started. The abdominal pain gradually diminished, and edoxaban was administered orally. On day 16, she was discharged from the hospital because there was no exacerbation of symptoms after the cessation of heparin. On day 60, contrast CT scan showed that the thrombus in the inferior mesenteric veins disappeared. The inferior mesenteric veins thrombosis might be associated with blood flow disturbance due to sigmoid volvulus. The present case is the first reported case of the inferior mesenteric veins thrombosis associated with sigmoid volvulus. The inferior mesenteric veins thrombosis could be one of the differential diagnoses in abdominal pain after endoscopic detorsion.

A 71-year-old man had positive fecal occult blood test, and colonoscopy was performed. Colonoscopy revealed a white color tumor which is 8-mm in diameter in the rectum. Endoscopic mucosal resection (EMR) was performed, the histological analysis showed the tumor was amelanotic malignant melanoma, which was localized within the mucosa. However melan A positive cells were spreading in the surrounding mucous membranes. We recommended additional surgery, but the patient refused it. After 6 weeks, follow-up colonoscopy revealed a melanosis near the EMR scar and biopsy showed malignant melanoma. Then the patient underwent surgery at another hospital. In our case, melanoma progressed in the epithelium. We consider that the histological diagnosis of the extent of the lesion has to be cautious.

A 47-year-old woman underwent colonoscopy for fecal occult blood examination, which revealed a yellowish colonic mucosa with disappearing permeability of the capillary vessel and scattered tiny brown spots. Pathology specimens of the colonic mucosa revealed aggregation of foam cells. In addition to these findings, low high-density lipoprotein cholesterol and apolipoprotein A-1 levels, numbness of the upper extremities, and resection history of the lipid-rich tonsils led to the suspicion or Tangier disease.

A 59-year old man had positive results of fecal occult blood test in the screening test. A colonoscopic examination revealed two elevated lesions looking like SMT, 10mm and 5mm in size, in the lower rectum. We performed diagnostic endoscopic submucosal resection with ligation device (ESMR-L) for a 10mm elevated lesion, performed diagnostic endoscopic mucosal resection (EMR) for a 5mm flat elevated lesion. The resected specimen of 2 lesions showed NET-G1, and the vertical and lateral margin were negative. A case of endoscopic submucosal resection of the multiple rectal NET is rarely reported.

A 59-year-old man diagnosed with alcoholic liver cirrhosis (LC) and rectal varices (RV) was admitted to our hospital because of recurrence of RV. He underwent endoscopic variceal ligation for RV. An abdominal CT scan suggested the inferior mesenteric vein had hepatofugal flow and mainly supplied RV. The blood flow rate of the RV was 20cm/sec as measured by Color Doppler ultrasonography, which was too fast to treat with endoscopic injection sclerotherapy. Therefore, we decided to treat the RV with percutaneous transhepatic obliteration (PTO). Moreover, partial splenic artery embolization was performed for portal hypertension before PTO. PTO was successfully performed, and the RV was embolized using ethanolamine oleate and microcoils. Colonoscopy revealed the complete disappearance of RV after PTO.

A 70-year-old man complained of persistent diarrhea for 6 months, and a colonoscopy in a previous hospital revealed a large rectal tumor. He was referred to our hospital for tumor resection. Our colonoscopy revealed a villous tumor (55-mm diameter) of flat elevated type in the rectum accompanied by mucus secretion, and magnifying endoscopy revealed a Kudo's type IV_B and IVv pit pattern. Thus, the tumor was diagnosed as carcinoma in tubulovillous adenoma, and endoscopic submucosal dissection (ESD) was performed. A pathological examination showed high grade tubulovillous adenoma. The diarrhea immediately disappeared after ESD. Mucus discharge in a large villous tumor may cause persistent diarrhea and electrolyte abnormalities. Previous reports have shown surgical resections of large rectal villous tumors; nowadays, ESD can be performed after a careful endoscopic examination.

A 69-year-old man visited our hospital with chief complaints of abdominal pain and vomiting. He was diagnosed as having choledocholithiasis and admitted for treatment. Although endoscopic retrograde cholangiopancreatography was attempted with a duodenoscope, the scope could not be advanced because of a stricture caused by esophageal cancer. A forward-viewing endoscope was passed through the esophagus, allowing observation up to the duodenum. Employing the forward-viewing endoscope, we performed endoscopic sphincterotomy and endoscopic papillary balloon dilation, followed by stone removal with a balloon. No complications occurred such that we were subsequently able to make a smooth transition to esophageal cancer treatment. Because there are cases in which stones can be removed with a forward-viewing endoscope, its use appears to be a possible therapeutic approach.

We report two patients of endoscopic diagnosis and treatment by using Spyglass™ DS. Case1: a 62-year-old man with an obstructive jaundice was admitted our hospital.Using Spyglass™ DS, we were able to reveal a benign biliary stricture. Case 2: a 77-year-old man with an obstructive jaundice was admitted our hospital.Using Spyglass™ DS, we were able to clearly visualize the stone and break it into pieces.Spyglass™ DS can be considered safe and effective.

A 100-year-old man was admitted for vomit. He received endoscopic treatment for common bile duct stones six years previously. Computed tomography (CT) revealed that the biliary stent had migrated into the small bowel, causing bowel obstruction. On hospital day 26, enteroscopy was performed to remove the biliary stent. However, a few stones were attached to the stent and we could not remove the stent. On hospital day 32, he underwent surgery to remove the biliary stent.

Case 2 was a 96-year-old man who was admitted for vomit. He received endoscopic treatment for common bile duct stones six months previously. CT revealed the same situation as in case 1. We attempted to remove the biliary stent by enteroscopy, but were not successful. On hospital day 66, the biliary stent was discharged naturally.

An 87-year-old female was diagnosed lower CBD cancer in January 2017. The patient refused resection but underwent placement of a biliary self-expendable metallic stent (SEMS). In April 2017, she presented with abdominal pain. Endoscopic cholangiography demonstrated SEMS occlusion by sludge and blood-clot. We performed endoscopic cleaning with a retrieval-ballon catheter. In September 2017, she was admitted with recurrent cholangitis. Fluoroscopy and endoscopic images demonstrated distal migration and fracture on the distal end of SEMS. We placed a 7Fr plastic stent (PS) through the broken SEMS. 1 week later, after removing the PS, alligator-forceps were used to grasp the distal end of the fractured SEMS, which was cautiously withdrawn from the CBD. Immediately after removal, we inserted a new SEMS. The patient was discharged without any complications.

We assumed that cleaning the SEMS with a balloon caused distal migration, followed by mechanical stress in duodenum caused the fracture. Although uncommon, fracture should be considered in patients with SEMS.

The patient, a 31-year-old woman, was diagnosed as having gallbladder wall thickening on an abdominal ultrasonography performed at a regular health checkup in 20XX and was subsequently referred to our department for examination. Ultrasonic endoscopy findings indicated gallbladder wall thickening around the entire circumference and polyp-like protruding lesions. Findings also revealed merging of the pancreas and bile duct outside of the duodenal wall. Endoscopic retrograde cholangiopancreatography revealed that the common bile duct diameter was 7mm and that the shared duct was 30mm, with the main pancreatic duct imaged from the intrapancreatic bile duct. Therefore, a diagnosis of malfusion of the pancreaticobiliary ducts (non-bile duct dilatation type) was made. As the possibility of early bile duct cancer could not be denied, laparoscopic cholecystectomy was performed. Pathological examination revealed multiple hyperplastic polyps with no findings suggestive of malignancy. Our experience suggests that if polypoid gallbladder lesions are observed in a young patient, careful testing should be implemented with the possibility of malfusion of the pancreaticobiliary ducts in mind.

A 69-year-old woman with a history of chronic pancreatitis and gallbladder stone was emergently transported to our hospital for sudden epigastric pain after ingesting alcohol. Her blood test showed elevated pancreatic enzyme levels, including amylase at 3515U/L. Although jaundice was not observed, there was a mild increase in hepatobiliary enzyme levels. Abdominal ultrasonography and computed tomography showed no stone in the common bile duct; however, we observed a fat stranding around the pancreas and made a diagnosis of acute pancreatitis. Although alcoholic pancreatitis was strongly suspected, we performed endoscopic ultrasonography (EUS) to rule out gallstone pancreatitis. On EUS, a 6-mm hyperechoic lesion with acoustic shadow was observed at the papilla; the patient was diagnosed with an impacted stone at the ampulla of Vater. Emergency endoscopic sphincterotomy and removal of the impacted stone were performed. EUS is useful for evaluating biliary obstruction in cases with gallstone pancreatitis and can diagnose impacted stone at the papilla. We strongly recommend EUS in cases with pancreatitis for which an indication of endoscopic retrograde cholangiopancreatography is uncertain.

A 73-year-old man developed alcoholic chronic pancreatitis seven years previously. He has undergone pancreatic stent exchange for stenosis of the main pancreatic duct at the pancreatic head on a regular basis starting two years ago. During stent removal at the present time, the stent ruptured and migrated further into the main pancreatic duct. We initially dilated the stenosis by a balloon catheter, but we could not retrieve the stent by using a basket and balloon catheter. We could grasp the papillary end of the migrated stent by a wire-guided one-sided opening-cup biopsy forceps, and succeeded in removing the stent. To remove a migrated stent especially when the stricture of the main pancreatic duct is severe, or when it is difficult to maneuver the guidewire into the stent, a wire-guided one-sided opening-cup biopsy forceps may be useful.