Chronic pancreatitis is one of the risk factors for pancreatic cancer and is considered to be an irreversible and progressive disease. However, the conventional diagnostic criteria of chronic pancreatitis had the problem of being able to diagnose only advanced chronic pancreatitis. Based on the hypothesis that the early stage of chronic pancreatitis is a reversible disease, the diagnostic criteria of “early-stage” chronic pancreatitis were developed in Japan for early detection and early treatment of chronic pancreatitis. Endoscopic ultrasonography (EUS) plays an important role in detecting “early-stage” chronic pancreatitis. Many EUS image findings of “early-stage” chronic pancreatitis are mentioned in the Rosemont criteria for the EUS diagnosis of chronic pancreatitis.

Barrett’s esophagus, a precursor of esophageal adenocarcinoma, occurs due to reflux of duodenal contents after total gastrectomy. We herein report a case of adenocarcinoma arising in long-segment Barrett’s esophagus 51 years after total gastrectomy. A 70-year-old woman who had undergone total gastrectomy with Billroth Ⅱ esophagojejunostomy reconstruction and Braun’s anastomosis for a gastric ulcer at 19 years of age, was referred to our hospital for detailed examination of a protruded lesion in the esophagus. Endoscopic examination revealed long-segment Barrett’s esophagus beginning 17 cm from the incisors and continuing to the esophagojejunostomy site, and a slightly reddish protruded lesion, 14 mm in diameter, that was located 18 cm from the incisors. Biopsy specimens taken from the lesion disclosed adenocarcinoma. We diagnosed it as adenocarcinoma in Barrett’s esophagus and performed endoscopic submucosal dissection. Histopathologic examination of cross-sections revealed well-differentiated tubular adenocarcinoma invading down to the deep muscularis mucosae. The surrounding esophageal mucosa was lined with columnar epithelium of intestinal type. The patient has continued to be followed frequently and has been recurrence-free for 2 years. Careful surveillance is recommended for patients with long-segment Barrett’s esophagus after total gastrectomy in order to detect adenocarcinoma early.

A 76-year-old woman with dysphagia due to progression of amyotrophic lateral sclerosis underwent percutaneous endoscopic gastrostomy (PEG). On postoperative day 2, the patient felt abdominal fullness. Radiography revealed an enlarged region from the small intestine to the transverse colon. Following the diagnosis of ileus, the stomach wall, which had been fixed for gastropexy during the PEG procedure, was unfixed, and her symptoms improved quickly. We believe that the site of paracentesis in this case may have been lower than usual and that the transverse colon was penetrated at the lower of the two wall-fixing points, resulting in ileus. Although preoperative upper gastrointestinal tract endoscopy and abdominal CT scanning are important for determining the appropriate site of paracentesis, adequate consideration should be given to confirm standard paracentesis positions at the time of the procedure.

An 85-year-old woman was referred to our hospital with the chief complaints of epigastric pain and nausea. Simple CT on admission showed that she had gastric volvulus and the oral side of the stomach had been extended. Contrast-enhanced CT suggested that blood flow in the pyloric region of the stomach was poor. Therefore, endoscopic gastric volvulus reduction using an Endoscope Position Detecting Unit (UPD) was performed. Her postoperative course was good and the patient was discharged from our hospital. Six months after gastric volvulus reduction, laparoscopic stomach fixation surgery was performed to prevent relapse, and the gastric volvulus has not relapsed. We succeeded in reduction of gastric volvulus by initially checking the direction of torsion of the stomach by using a UPD.

A 45-year-old male was undergoing regular follow-up observations for primary sclerosing cholangitis (PSC) and ulcerative colitis. He was referred to our department when the results of a CT scan performed before total colectomy revealed bile duct wall thickening. Ultrasound, CT, and MRI examinations revealed a 2-cm papillary mass in the anterior segmental bile duct. Endoscopic retrograde cholangiopancreatography revealed a filling defect in the anterior segmental bile duct. Peroral cholangioscopy revealed a papillary mass that filled the lumen of the anterior segmental bile duct and granular mucosa in the lower bile duct. Biopsy results led to the diagnosis of intraductal papillary neoplasm of the bile duct (IPNB). Right lobectomy and extrahepatic bile duct excision were performed. In this case, peroral cholangioscopy was useful for diagnosing the extent of superficial infiltration of the IPNB and for planning the surgical procedure.

A 71-year-old man who had undergone transduodenal sphincteroplasty for carcinoma of the papilla of Vater at a different hospital ten years previously, was referred to our hospital because of fever and nausea. Abdominal computed tomography demonstrated choledocholithiasis, and we diagnosed obstructive jaundice and cholangitis. After conservative therapy, endoscopic retrograde cholangiopancreatography (ERCP) revealed stenosis of the papilla of Vater as a result of postoperative change and multiple bile stones. Therefore, we performed endoscopic sphincterotomy (EST) and endoscopic papillary large balloon dilation (EPLBD), and the bile duct stones were successfully removed without complications. We considered that EST should be the first choice of treatment for choledocholiths after transduodenal sphincteroplasty.

Endoscopic imaging methods have been divided into five categories by object-oriented classification. Narrow band imaging (NBI) is within the category of “Image-enhanced endoscopy”. A new system of NBI, the Lucera Elite^®, has stronger light power, enabling the endoscopist to observe details of colorectal lesions. In order to obtain clear images, it is important to wash out the covered mucous completely from the surface of the mucosa by using hot water.

With NBI, the imaging of mucosal microcapillary vessels and surface structure in the superficial layer of colon tumors can be emphasized. One of the benefits of NBI observation is that neoplasia can be easily recognized as a brownish area. According to JNET classification, colorectal lesions were classified into three types by Japanese NBI expert team with the shape of microcapillary vessels and surface structure on the surface of the tumor. Type 1 is defined as a sessile serrated lesion, especially a hyperplastic polyp. In contrast, type 3 is defined as submucosal deeply invasive cancer (SM cancer). Type 2 is divided into two subgroups, 2A and 2B. Type 2A includes mostly tubular adenomas and is an indication for endoscopic treatment, while type 2B includes intramucosal cancer and SM cancer. Further examination by using chromoendoscopy with magnification is necessary for colorectal lesions that are suspected to involve submucosal invasion.

Meanwhile, Kudo and Tsuruta pit pattern classification is commonly used in Japan. There are five types of pit patterns, type Ⅰ (one) to Ⅴ (five). Type Ⅰ is observed in normal colon mucosa. Type Ⅰ includes NET G1 (carcinoid tumor), malignant lymphoma and so on. Type Ⅱ is defined as a sessile serrated lesion, which is observed as star-shaped. Types Ⅲ to Ⅴ pit pattern are thought to have a neoplastic character. Type Ⅲ pit pattern is divided into two subtypes, Ⅲ_L and Ⅲs. Type Ⅲ_L includes typical common polyps and is observed as tubular adenoma on histological examination. In contrast, the Ⅲs pit is characteristic of depressed lesions, such as Ⅱc type, Type Ⅳ pit pattern is commonly observed in villous type tumors. Type Ⅴ pit is also divided into two subtypes. One is the Type Ⅴ_I (irregular) pit pattern and another is Ⅴ_N (non-structure) pit pattern. The Type Ⅴ_I pit pattern is observed in intramucosal cancers, tubular adenoma with high-grade dysplasia, or SM cancer. Therefore, it is necessary to carefully observe the details of pit pattern by using crystal violet staining. Type Ⅴ_N pit pattern is often observed in SM cancers with deep invasion. These lesions are an indication for surgical resection.

The relationship between conventional endoscopic observation and magnified endoscopic observation can be compared to two wheels of a bicycle. It is important to use both methods to increase the accuracy of pre-operative diagnosis of the depth of invasion and to develop a treatment strategy.

A pedunculated polyp is an indication for conventional polypectomy, while a polyp that is sessile or flat and is large or suspected of being cancer is an indication for endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD). Cold polypectomy is indicated for a small (≤10mm) sessile or flat polyp that is not suspected of being cancer.

In polypectomy for a pedunculated polyp, the snare should be placed close to the polyp head. In cases where the stalk of the polyp is very thick, it is recommended that an endoloop be applied to the base of the stalk before cutting with a snare for the purpose of preventing hemorrhage. In cold polypectomy, a certain distance between the snare wire and the polyp margin should always be maintained during closure of the snare in order to secure a tumor-free margin. The success of EMR largely depends on how the solution is injected. In the case of a lesion lying over a flexure or a fold, injection should be started from the proximal side. If the lesion is large, injection can be done through the center of the lesion as long as it is not suspected of being invasive cancer. In order to obtain a good lift of the lesion, the tip of the needle should be slightly lifted and slowly withdrawn during the injection. The snare should be pushed against the colonic wall during an attempt to capture the lesion, but not too much in order not to involve the proper muscle layer. If the patient complains of pain or if the assistant feels much resistance during cutting with the electric current, the procedure should be suspended as the muscle layer might be involved.

Background and Aim : There are limited studies on incidence rates of metachronous neoplastic lesions after resecting large colorectal polyps. In the present study, we analyzed metachronous lesions after endoscopic resection of colorectal polyps ≥20mm in size.

Methods : We retrospectively analyzed consecutive patients who underwent endoscopic resection of polyps from 2006 to 2013 at two affiliated hospitals. All patients underwent at least two total colonoscopies before follow up to ensure minimal missed polyps. Only patients who had follow-up colonoscopy annually after resection were recruited. We separated patients according to size of polyp resected; there were 239 patients in the ≥20-mm group and 330 patients in the <20-mm group. Clinical characteristics and cumulative rates of metachronous advanced adenoma and cancer in both groups were analyzed. Advanced adenoma was defined as a neoplastic lesion ≥10mm in size and adenoma with a villous component.

Results : Cumulative rate of development of metachronous advanced adenoma and cancer in the ≥20-mm group was significantly higher than in the <20-mm group (22.9% vs 9.5%, P<0.001) at 36months. There was also more development of small polyps 5-9mm in the ≥20-mm group than in the <20-mm group (45.2% vs 28.8%, P<0.001). With respect to metachronous lesions, there were more right-sided colonic lesions in the ≥20-mm group than in the <20-mm group (78.8% vs 50.0%, P = 0.015).

Conclusion : High incidence rates of development of metachronous neoplastic lesions were detected after resection of colorectal polyps ≥20mm in size.