【背景】遅発性ポリペクトミー後出血（delayed post-polypectomy bleeding：DPPB）は大腸内視鏡ポリペクトミーの偶発症の一つであり，緊急内視鏡的止血術を含む迅速な対応を要する．しかし，DPPBを呈した症例の中で，どのような症例が緊急内視鏡的止血術となるかは明らかではない．本研究はDPPB症例において緊急内視鏡的止血術と関連する因子を特定することを目的とした．【方法】本研究はとよしま内視鏡クリニック単施設で行われた後向き・症例対象研究である．DPPBを呈した症例を緊急内視鏡的止血術を受けた群と経過観察された群に分け，年齢，性別，切除したポリープの数・径（総計・最大）・形態，内視鏡的粘膜切除術（endoscopic mucosal resection：EMR）の有無，クリッピングの有無について，二項ロジスティクス回帰モデルを用い比較した．【結果】期間内にポリペクトミーを受けた14,008例のうち52例（平均54.1歳，男性53.8%）がDPPBと診断された．止血群は38例，経過観察群は14例であった．止血群は男性が多く（63.2% vs. 28.6%），ポリペクトミー径総計（16.6 mm vs. 11.3 mm）と最大（9.9 mm vs. 6.7 mm）が大きく，形態が0-I型を含むことが多く（94.7% vs. 50.0%），EMR施行例が多かった（63.2% vs. 14.3%）．【結論】DPPB症例では男性，大きいポリペクトミー径，0-I型ポリペクトミー，EMR施行例は止血術にいたる可能性が高いことを念頭に診察するとよい．今後は前向き試験が望まれる．

昨今，多様な働き方が求められる中で，個々の内視鏡医の置かれている環境も多様となった．個々人での知識のアップデートが難しいケースもある．そのため，学習やネットワーキングのための多様な選択肢を用意し，各々にとって，学びやすい環境を作る事が求められる．

本稿では，生涯学習およびネットワーキングの方法の一つ（あくまで一つ）として，ソーシャルメディアを用いた学びの提案を行うとともに，実際の運用を例として，その利点，問題点に関しても触れる．

内視鏡的粘膜下層剥離術（ESD）は大腸腫瘍に対する標準的治療として確立され，病変サイズや形態，線維化の有無に関わらず一括切除率が高いという利点がある．一方でESDは技術的難易度が高く，穿孔や出血などの偶発症のリスクを伴う．現在，様々なトラクションデバイスが開発されており，安全かつ効率的にESDを施行するうえで有用である．

新規トラクションデバイス（ディスポーザブル把持鉗子LA-400-01）を用いることで，上行結腸の30 mm大0-Is病変に対してtraineeが偶発症なくESDを施行し得た．本デバイスは牽引部位や牽引強度を適宜調整することで，粘膜下層剥離に必要な安定した視野確保が得られる．文献的考察を加えて本デバイスの有用性について報告する．

【目的】急性下部消化管出血に対する緊急内視鏡検査の有用性に関する多施設ランダム化比較試験において, 抗血栓薬の継続, 休薬が及ぼす退院後の長期予後の検討を行った.

【方法】2016年6月から2018年5月の間に血便で受診した159例のうち, 抗血栓薬を服用している76例を解析した. 退院時の抗血栓薬の継続群 (50例), 休薬群 (26例) の365日以内の再出血率, 血栓症発生率, 輸血率, 死亡率を比較した.

【成績】休薬群は再出血率 (0 vs 10%), 輸血率 (0 vs 6%), 死亡率 (3.6 vs 6%) が継続群と比べて低率であった. 血栓症の発生は両群に認められなかった. 継続群の再出血ハザード比は4.46 (95%信頼区間, 1.00-17.8) であった. 再出血を生じた5例の内, 4例が抗血栓薬を多剤継続していた. 再出血源は3例が大腸憩室出血であった.

【結論】下部消化管出血の退院後の抗血栓薬の継続は, 長期の高再出血率と関連する可能性が示唆された. 特に複数の抗血栓薬を使用する患者において, 退院後の抗血栓薬の管理は, 循環器専門医, 脳神経専門医, および主治医との連携が非常に重要である. これらの結果を検証するためには, さらなる大規模な研究が必要である.

A 56-year-old male was diagnosed as right lower pharynx carcinoma by upper gastrointestinal endoscopy gastrointestinal endoscopy, and underwent endoscopic laryngo-pharyngeal surgery to resect the lesion. The iodine-unstained area was suspected of being cancerous and was also resected. The resected area may adhere to surrounding tissues, which may affect the patient's swallowing function in the future. Local injection of triamcinolone acetonide to the desquamated site to prevent adhesions did not result in stenosis during postoperative follow-up.

A patient in her 50s with an unruptured left internal carotid aneurysm was prescribed two anti-platelet agents (aspirin and clopidogrel) before coil embolization. Under general anesthesia, coil embolization of the aneurysm was performed. Following extubation, the patient vomited blood and felt strong pain in her upper abdomen. Based on contrast-enhanced computed tomography and endoscopy, we diagnosed her as having an esophageal submucosal hematoma. Conservative therapy led to good healing as indicated by follow-up endoscopy. Esophageal submucosal hematoma is rare. In the present case, anti-platelet agents appeared to have been the main cause of the esophageal submucosal hematoma. The possibility of this complication should be kept in mind when administering anti-thrombotic therapy prior to endovascular neurosurgery.

A 74-year-old woman visited our hospital with a chief complaint of anterior thoracic discomfort while eating. Esophagogastroduodenoscopy (EGD) revealed two type 2 neoplastic lesions in the 24 cm and 32 cm incisors. Squamous cell carcinoma was observed on histopathological examination. Contrast-enhanced CT showed lymph node and liver metastases, and cStage 4b (T3N3M1) was diagnosed. Ten courses of pembrolizumab plus chemotherapy were administered. Hepatotoxicity developed as an immune-related adverse event after the 10 courses but was resolved with prednisolone (1 mg/kg). Contrast-enhanced CT showed shrinkage of the lymph nodes and disappearance of the liver metastases. Scarring of both esophageal lesions appeared on EGD, and no cancer was detected. The response to the chemotherapy was considered to be complete. We report a rare case of complete response in a patient with unresectable esophageal cancer.

A 72-year-old male had a well-defined 3×3 mm elevated lesion on the cervical esophagus, displaying JES classification type B2 blood vessels on the surface. Type B1 blood vessels were observed on the surrounding flat lesion. The superficial esophageal cancer was diagnosed as 0-IIa+IIb/cT1a-MM, and removed by endoscopic submucosal dissection. Pathologically, the elevated lesion with B2 blood vessels showed granulation tissue, while the elevated edge and B1 blood vessel area exhibited squamous cell carcinoma. The final diagnosis was SCC, pT1a, LPM, INFa, ly (−), v (−), pHM0, pVM0. B2 blood vessels are abnormal vessels with a sparse loop structure, commonly observed in deeper invasive esophageal cancers (MM-SM1). However, similar vessels were reported in inflammatory tissues. This case could not be differentiated from B2 vessels in cancer. This case showed that B2 blood vessels, defined as abnormal vessels seen in cancer, also occur in benign granulation tissue.

A male in his 80s was diagnosed with reflux esophagitis and Barrett's esophagus, and underwent endoscopy annually. After treatment for chronic pharyngeal mycosis, he developed scar stenosis at the esophageal orifice and regular follow-up was performed with a small-caliber endoscope. A depressed lesion was found in the esophagogastric junction (EGJ), and biopsy examination revealed adenocarcinoma (tub1). The preoperative diagnosis was Barrett's esophageal adenocarcinoma (depth, DMM-SM1). After endoscopic balloon dilatation, a therapeutic endoscope could be inserted and endoscopic submucosal dissection (ESD) was performed. Pathological examination revealed poorly differentiated adenocarcinoma, pT1b-SM2, ly1, v1, pHM0, pVM0. He desired no additional surgery. Five months later, lymph node and distant metastases developed.

Using a small small-caliber endoscope requires more careful observation for early detection of Barrett's esophageal adenocarcinoma because of its limited maneuverability compared to with that of the standard endoscope.

A 60-year-old woman diagnosed with cT2N0M0 esophageal cancer responded to chemoradiotherapy and had no metastasis or tumorigenesis for a year. She presented later with abdominal discomfort that lasted for 2 weeks. Upper gastrointestinal endoscopy found no esophageal abnormalities but gastric mucosal irregularities due to a cluster of erythematous, elevated lesions spreading from the fundus on the greater curvature of the upper body and anterior wall of the middle body. A biopsy showing the presence of mycelial threads led to a diagnosis of gastric candidiasis. Her symptoms and endoscopic findings improved after a 14-day oral fluconazole therapy. We report a rare case of gastric candidiasis, which showed typical endoscopic findings of candidiasis associated with ulcerations, and review the literature on gastric candidiasis.

A 78-year-old man with a history of diabetes visited our hospital complaining of abdominal distension after eating a lot of persimmons in a month. Abdominal computed tomography revealed spherical, air-containing, and low-absorption masses in the stomach and transverse part of the duodenum. Esophagogastroduodenoscopy revealed persimmon bezoars at the same sites. For treatment, cola was locally injected into bezoars, which were crushed by snares and collected subsequently. Additional oral administration of cola for 4 days removed all small bezoars after endoscopic treatment. Finally, the patient recovered well without any complications.

A 79-year-old female was referred to our hospital with a submucosal tumor (SMT) in the gastric angle found on plain computed tomography (CT) at another hospital. Esophagogastroduodenoscopy (EGD) showed a submucosal protuberance with small ulcers in the gastric angle, and biopsy showed no malignant findings. Contrast CT showed a 40-mm SMT in the gastric angle. EUS showed the mass as a well-defined 30-mm mass arising from the third layer, with a mixture of hypoechoic and hyperechoic features. EUS-FNA and biopsy showed no malignant findings. Three months later, EGD and contrast CT showed mildly enlarged ulcers. Reexamination of the EUS-FNA and pathology results revealed a small aggregate of epithelial-like cells with a background of mucus, and mucus-rich clear cytoplasm. Suspecting gastric mucinous carcinoma, laparoscopic pyloric gastrectomy was performed, and the pathological diagnosis was mucinous adenocarcinoma, pStage IA (pT1bN0M0).

We came across two cases of gastric neoplasms. Both the cases showed erythematous lesions in the body of the stomach and were resected en bloc by endoscopic mucosal resection. The pathology was adenoma, MUC5AC-positive, and MUC6-negative, and the diagnosis of foveolar-type gastric neoplasm was made.

Compared to hyperplastic polyps, foveolar-type gastric neoplasms are characterized by a bright color and a narrow white zone on magnified narrow-band imaging. Since the neoplasm may be resolved by biopsy, endoscopic resection is recommended as a treatment when this disease is suspected.

A woman in her 40s underwent upper gastrointestinal endoscopy after an abnormality was detected during a physical examination. A 7-mm-sized, well-defined, faded, elevated lesion was observed in the greater curvature of the lower gastric body. This lesion was suspected to be an adenoma, and endoscopic submucosal dissection (ESD) was performed. Pathologically, the lesion was a tubular adenoma. The background mucosa had inverse atrophy, and the anti-gastric wall cell antibodies were more than 160 times higher than those of the previous case, along with elevated gastrin levels and low levels of vitamin B12. It is said that gastric mucosa with autoimmune gastritis has a high risk of developing gastric cancer or neoplastic lesions, and appropriate diagnosis and continuous follow-up are recommended.

Duodenal adenoma is safely resected with energization by using gel immersion technique.

Recently, cold snare polypectomy (CSP) has been shown to be a promising procedure for the resection of small duodenal adenoma. Since underwater CSP is effective and safe for colorectal diminutive adenoma, we report a case of superficial duodenal adenoma treated using gel immersion CSP. The 8 mm superficial lesion was located at the descending portion of the duodenum. After 200 mL of gelatinous liquid was injected, remaining air in the lumen was suctioned to put the lesion under the gel. Subsequently, the lesion was resected using a specialized snare. Diagnosis was low-grade adenoma with negative surgical margin. No complications were observed. This was the first report of gel immersion CSP for a superficial duodenal adenoma. Using gel immersion instead of water allowed the liquid to remain in the duodenal lumen.

A 90-year-old woman experienced gastritis due to an immune-related adverse event (irAE). Two years earlier, she had been diagnosed with recurrent postoperative lung adenocarcinoma (cT2aN0M1, Stage IV) and had received three courses of pembrolizumab, which she responded well to. However, she suffered from intense abdominal pain and acid reflux after eating for over a year. During a repeated esophagogastroduodenoscopy, the examination revealed stiffness in the gastric wall in the antrum, raising concerns about scirrhous carcinoma. However, biopsy results did not indicate malignancy; instead, they showed severe inflammation, and CD8 antibody staining was positive. Based on clinical and immunopathological assessments, she was diagnosed with irAE gastritis. After initiating steroid treatment, her condition improved significantly, and she fully recovered from her difficulty with oral intake.

A 76-year-old woman complained of upper abdominal pain and vomiting. She ate three persimmons a day every autumn. Esophagogastroduodenoscopy revealed a 10-cm dark brownish stone in the greater curvature of the gastric body and an ulcer in the lesser curvature of the angulus. Hence, dissolution therapy for gastric phytobezoars was started; however, it was only mildly reduced. Therefore, endoscopic lithotripsy was performed, which resulted in the complete removal of the gastric phytobezoars. Gastric phytobezoars can be treated by dissolution therapy or endoscopic lithotripsy. In this case, the gastric phytobezoars could not be completely dissolved, and endoscopic treatment was needed for complete removal. Although carbonated water is useful for the dissolution of gastric phytobezoars, combination of endoscopic crushing might be desirable.

A man in his 80s underwent ESD for a 30 mm-sized gastric cancer located in the greater curvature of the cardia region. Though it was diagnosed as tubular adenocarcinoma T1b, the surgical margin was positive. Additional surgical resection was proposed but not selected due to advanced age.

Five years after ESD, a 10 mm-sized submucosal tumor-like lesion was found near the post-ESD scar. Endoscopic ultrasound (EUS) revealed a hypoechoic mass contiguous with the fourth layer. Since the surface was smooth, EUS-guided fine needle aspiration (EUS-FNA) was performed for the diagnosis. The pathological finding was adenocarcinoma.

Even in tumors with little change on the mucosal surface, tissue sampling by EUS-FNA may be useful in determining the diagnosis of gastric cancer.

We report three cases of FGA-RA treated endoscopically. These rare neoplasia, occurring in non-atrophic fundic gland mucosa, were successfully treated in patients aged 50-74. Endoscopic treatments included ESD for one case and EMRL for the others. Pathological findings confirmed FGA-RA. All cases underwent complete resection without complications. Our experience suggests that both ESD and EMRL offer curative potential for this type of neoplasia, presenting a valuable treatment avenue.

A 40-year-old man with a history of vascular graft implantation for abdominal artery aneurysm and a suspected graft infection presented to our hospital with melena for a few days. Laboratory data showed marked anemia (Hb 5.2 g/dl). There was no extravasation detected on enhanced CT images. We suspected diverticular bleeding and performed emergency colonoscopy but could not identify the bleeding site. To rule out excessive upper gastrointestinal bleeding, we performed an upper endoscopy and found that a wall of the graft was exposed to the duodenum. Emergency stent graft implantation was performed and the bleeding subsided. On day 10 after admission, we performed surgical repair of the fistula. For a patient presenting with melena with a history of surgical repair of an abdominal artery aneurysm, it is important to look for signs of secondary aorto-enteric fistula on enhanced CT imaging.

A woman in her 70s visited our hospital complained of her jaundice. She had a history of pyloric gastrectomy, extended left hepatic lobectomy, and Billroth-II reconstruction 17 years ago due to hepatic metastasis of a duodenal tumor initially diagnosed with duodenal adenocarcinoid. Enhanced CT scan showed multiple intrahepatic tumors and a hypervascularized tumor in the pancreatic head caused obstructive jaundice. By performing cholangiography using a double-balloon endoscopy, a plastic stent was implanted in stenosed common bile duct and successfully improved her jaundice. Percutaneous biopsy of the hepatic tumor subsequently revealed tissue similar to that of resected tumor 17 years ago. In addition to the immunostaining results, we concluded the diagnosis of recurrence of duodenal NET. NETs are known to recur at a high rate even after curative resection, but cases of recurrence more than 10 years after curative resection are comparatively rare. Therefore, we reported this case here with a discussion of the literature.

A woman in her 80s was previously diagnosed with a ring ulcer in the descending part of the duodenum. She experienced recurrent ulcerations in the same part of the duodenum. The resulting scars caused progressive narrowing of the duodenum, thereby preventing oral intake. As the quality of health and daily life of the patient were considerably affected over the next 6 months, she visited our hospital for a second opinion. Esophagogastroduodenoscopy and catheter duodenography revealed a pinhole stenosis (approximately 3 mm in length) in the descending part of the duodenum. Therefore, endoscopic dilatation was performed in stages over a period of 4 days. Moreover, special attention was paid to complications that might arise with the dilatation process. On the first day, dilation was started with a 6 mm balloon, and finally an 18 mm balloon was used on the fourth day. Thereafter, the patient was able to eat again. We conclude that our technique may be useful for patients with benign duodenal stenosis.

The frequency of ileal neuroendocrine tumor (NET) is low in Japan, accounting for only 0.6% of all gastrointestinal NETs.

A 53-year-old male was found to have a 5 mm-diameter reddish submucosal tumor (SMT)-like lesion in the terminal ileum by colonoscopy. Histological examination of the biopsied specimen led to the diagnosis of NET. Endoscopic ultrasound (EUS) showed a hypoechoic structure in the second and third layers, and endoscopic submucosal dissection (ESD) was performed. The ESD was regarded as a non-curative resection due to the pathologic finding of lymphatic invasion by immunostaining with D2-40. Therefore, laparoscopic ileal resection with D3 lymph node dissection was performed.

Even Small lesions of ileal NET have been reported to metastasize. During colonoscopy, endoscopists should observe the terminal ileum carefully and biopsy SMT-like lesions intentionally.

We report a case of a 38-year-old man who complained of abdominal pain and was diagnosed with intestinal tuberculosis. Ileocolonoscopy revealed white submucosal tumor (SMT) -like lesion at the terminal ileum and cecum. A biopsy of a white SMT-like lesion revealed caseating granulomas on pathological examination. He was diagnosed with intestinal tuberculosis, and received antituberculous therapy. A combination of rifampicin, isoniazid, pyrazinamide, and ethambutol was used for 2 months, followed by a combination of rifampicin and isoniazid for 4 months.

Endoscopic findings of intestinal tuberculosis are typically ring-shaped and band-shaped erosions and ulcers, in contrast, SMT-like lesion are rare. According to the Kuromaru's classification (pathological classification of intestinal tuberculosis), the white SMT-like lesion is classified as an early image of tuberculosis. In fact, in this case, SMT-like lesion led to the diagnosis of intestinal tuberculosis. Therefore, although SMT-like lesion is rare as a finding of intestinal tuberculosis, it should be included in one of the differential diseases.

The endoscopic removal of colonic foreign body. The AA battery was removed endoscopically from the asending colon. Net was used removal. No complication was observed.

A foreign body sometimes brings on the perforation, bleeding. Surgical procedures are necessary for these cases. Endoscopic removal of foreign body is popular method for upper gastrointestinal tract. But it is rare for lower intestinal tract. We concluded that the endoscopic removal of colonic foreign body is a safe and effective method.

A 70-year-old woman presented to our hospital with a positive fecal occult blood test and a 3-year history of taking a herbal medicine (shiniseihaito) for chronic sinusitis. A Computed tomography scan showed no mesenteric vein calcification and a colonoscopy revealed a dark bronze-colored mucosa from the ileocecal region to the ascending colon. Histopathological examination showed fibrous thickening of the vein wall in the lamina propria and submucosal layer, diagnosing mesenteric phlebosclerosis. The patient stopped taking shiniseihaito, and endoscopic evaluations a year later showed an improvement in the color tone from the ileocecal region to the ascending colon. Furthermore, if endoscopic findings exhibit a peculiar dark bronze-colored mucosa, even without mesenteric vein calcification, it may be necessary to perform an aggressive mucosal biopsy. It is important to consider the patient's history of taking herbal medicine containing gardenia fruit when diagnosing.

A 42-year-old woman was referred to our hospital with a complaint of abdominal pain. An abdominal CT scan revealed intussusception caused by a tumor of the sigmoid colon. The intussusception could not be unfastened by colonoscopy. Sigmoidectomy was performed. The histological diagnosis of the tumor was a benign neurogenic tumor. Adult intussusception often results from organic disease. Neurogenic tumors in gastrointestinal tract are rare.

The patient was a woman in her 40s who was referred to our hospital with chief complaints of constipation and abdominal pain during defecation. Colonoscopy at her previous doctor pointed out stricture in the sigmoid colon. Abdominal pain was characterized by aggravation during menstruation. A biopsy was performed from the reddened site as a differential diagnosis of metastatic tumor, intestinal endometriosis, etc. Abdominal and pelvic contrast-enhanced computed tomography revealed no obvious neoplastic lesions. Histopathological examination identified endometrial tissue in the biopsy specimen and reached the diagnosis of intestinal endometriosis. Reports of intestinal endometriosis with circumferential stenosis are rare.

It is important for the endoscopist to first suspect this disease based on the patient's medical history, and when the exposed lesion is shown on the mucosal surface, the endoscopist should perform a biopsy and inform the pathologist of the suspicion of intestinal endometriosis.

Case 1: A 91-year-old woman swallowed her denture, as discovered via radiography four days after the denture was lost. The horseshoe-shaped denture was found in the hypopharynx upon emergency endoscopy. Grasping forceps were used to pull, the denture up to the oral cavity where they were removed by hand. A bleeding ulcer observed in the oropharynx. The ulcer was successfully treated by an antibiotic, proton pump inhibitor, no oral intake for one week. Case 2: A 58-year-old man presented after accidentally ingesting his denture. He had no fever or abdominal pain. The denture was located at the ileocecal valve via the abdominal X-ray three days after the ingestion. Lower endoscopy was preformed to remove the denture by using the Roth net Olympus Foreign body ingestion is a common issue among the elderly. Some foreign bodies, such as dentures are sharp and may severely damage the gastrointestinal tract. Sharp foreign bodies should be removed endoscopically. However, if endoscopic resection is difficult, surgery may be necessary.

A man in his 60s had a 6-month history of back pain and abdominal distension. He was referred to our hospital with suspected colorectal cancer as his previous doctor had identified a wall thickening in the descending colon on computed tomography as well as anemia.

Colonoscopy showed a 5-cm long submucosal tumor-like elevated lesion. A biopsy revealed amyloid deposits, and due to a lack of obvious damage in the other organs, a diagnosis of localized AL (amyloid light-chain) amyloidosis was made. Subsequently, a bone marrow biopsy revealed multiple myeloma, and the patient was transferred to the Department of Hematology for systemic chemotherapy.

In AL amyloidosis, amyloid is deposited mainly in the submucosal layer and presents characteristic endoscopic findings. In the present case, colorectal amyloidosis triggered the diagnosis of multiple myeloma.

A 51-year-old female was referred to our hospital for examination of colorectal tumor. Conventional endoscopy revealed four aggregated colorectal lesions in the ascending colon, consisting of three 0-IIa+IIc lesions and one 0-IIa lesion with a white scar at the center of these lesions. As endoscopic complete resection of all lesions was thought to be difficult due to the central white scar, surgical resection was scheduled. However, in the endoscopic examination just before surgery, 90 days after the initial endoscopic examination at our hospital, three lesions had regressed spontaneously while one 0-IIa+IIc lesion remained with no morphological change. Endoscopic mucosal resection was performed for the residual lesion with complete resection, and histological examination revealed slightly invasive submucosal cancer with a depth of 260 μm without lymphovascular invasion. Spontaneous regression of colorectal cancer is extremely rare. We speculated the cause of spontaneous regression based on previous reports.

A man in his 70s with lower gastrointestinal bleeding was admitted to the emergency department. The next day, a total colonoscopy (TCS) revealed blood clots in a sigmoid colon diverticulum. When the clots were removed, pulsatile bleeding occurred, and hemostasis was achieved using the clipping method. On day 4, bloody stool was observed, and TCS was performed for hemostasis with an additional clip. On day 6, hematochezia was again observed, and TCS revealed bleeding from the same site. Another clip was added and 3 mL of an absorbable local hemostatic agent (PuraStat^®; 3-D Matrix) was applied. No further bleeding was observed. Our technique may be useful to treat cases of diverticular hemorrhage with a high risk of rebleeding.

An 81-year-old male patient underwent a screening colonoscopy, during which a 6 mm 0-IIa lesion was detected at the appendiceal orifice. To enhance visualization and confirm the nature of the lesion, we employed narrow-band imaging magnification, using which we confirmed that the lesion was a colorectal adenoma (JNET Type 2A). Consequently, we performed an underwater cold snare polypectomy (U-CSP) along with a two-part CSP and resection using biopsy forceps. In conclusion, our study demonstrates that U-CSP is an effective technique for managing appendiceal orifice lesions, allowing for accurate qualitative diagnosis and complete removal of lesions. This technique can contribute to reducing the risk of recurrence and the need for additional interventions, ultimately improving patient outcomes.

We report the case of a man in his 70s with a history of diabetes mellitus, hypertension, and dyslipidemia. He underwent annual colonoscopic examination for colonic polyps, which revealed submucosal tumor-like elevated lesions, diffusely spread the sigmoid colon. The lesion had a smooth surface with central erosion. Endoscopic ultrasonography revealed a hypoechoic area in the submucosal layer. We performed endoscopic mucosal resection for pathological confirmation. Histopathological findings in a cut section revealed invaginated mucosa with inflammatory cell infiltration and mucin-containing cystic lesion in the submucosal layer, without any fibromuscular obliteration. Immunohistochemical analysis showed invaginated mucosa with CK20-immunopositivity and CK7-immunonegativity. Etiology underlying colonic mucosal invagination into the submucosal layer remains unclear. The patient is being followed up annually.

A Japanese woman in her 20s who complained diarrhea and bloody stools was diagnosed as ulcerative colitis (UC) and treated with Mesalazine.

She was referred to our hospital three years later with worsening symptoms and a vulvar ulcer. The colonoscopy image and pathological finding was compatible with UC from the rectum to the sigmoid. However there were small deep ulcerations like Crohn's disease (CD) or Behçet disease (BD) in the transverse colon. Prednisolone improved the symptoms.

The vulvar ulcer is common in BD but it is an extremely rare extraintestinal manifestation (EIM) in UC. This case was considered unclassified inflammatory bowel disease (IBDU) and the diagnosis may be confirmed with the change of the endoscopic finding and appearance of EIM in the future.

This patient in his 80s was transferred for suspected intestinal obstruction. Sigmoid volvulus was diagnozed by "coffee-bean sign" in abdominal X-ray and obstruction of the sigmoid colon with whirl sign in contrast-enhanced CT. Endoscopic detorsion was attempted but was in vain due to strong torsion and poor blood flow. Symptoms were temporarily relieved with endoscopic degassing. Three days later, abdominal distention recurred. The following colonoscopy showed worsened torsion and exposure of muscular layer, implicating impending perforation. Poor general condition made surgical intervention too risky. Insertion of a transanal ileus tube for decompression was considered, but the hard and thick tip made it impossible to be passed through the site of impending perforation. Instead, we placed a urinary ballooned (Foley) catheter and successfully decompressed. Symptoms were fully relieved without perforation during the course.

Male, in his 20s chief complaint fever and diarrhea. Blood tests showed WBC15,600 and CRP4.9, and CT scan showed thickening of the colonic wall in primary care clinic. Blood tests in our hospital showed WBC12,130, CRP5.0, CMV-IgM13.4, IgG93.7 and CMV antigenemia negative. CT scan showed splenic infarction, wall thickening of the ascending to transverse colon. Colonoscopy revealed multiple erosions in the terminal ileum and scattered erosions and shallow ulcers in the right-sided colon. Histopathology showed chronic inflammatory cell infiltrates, with no apparent nuclear inclusion bodies; CMV immunostaining showed plasma cells with positive cytoplasm, as well as large cells with indistinct nuclear morphology and positive whole cells. Diagnosis of enteritis associated with cytomegalovirus infection. We experienced a case of cytomegalovirus enteritis in a healthy subject.

Case 1: A 70-year-old woman was admitted for a common bile duct stone and underwent endoscopic retrograde cholangiopancreatography (ERCP). After endoscopic sphincterotomy (EST) and papillary large-balloon dilation, the stone was removed. Seven days later, she developed melena and anemia. Therefore, duodenoscopy was performed, which showed bleeding from the major papilla.

Case 2: A 60-year-old man was admitted for jaundice and bile duct dilation. Computed tomography showed bile duct dilation but no obstructive lesion. Therefore, ERCP was performed. Duodenoscopy showed enlarged oral protrusion of the major papilla. Bleeding occurred when EST was performed.

In both cases, red dichromatic imaging (RDI) afforded improved visualization of bleeding points, which appeared darker yellow than the surrounding blood. Hemostasis was achieved by hemoclip application. RDI was effective in affording visualization of post-EST bleeding.

A man in his 60s presented with epigastralgia and fever. Single-balloon endoscopy revealed pinhole-like stenosis at the bile duct jejunal anastomosis. After balloon dilation and placement of a plastic stent at the site, his symptoms improved. Stenosis at the anastomotic site within 1 year after bile duct jejunal anastomosis is a risk factor for restenosis after dilation, and he had undergone double-balloon endoscopic dilation 12 months after the anastomosis 11 years earlier. Because of the difficulty of the endoscopic approach, a single stent was placed for 1 year, whereas multiple stents should have been placed and replaced periodically. Despite the limited treatment of this high-risk case, the anastomotic site remained open for 10 years. These results suggest that long-term placement of a stent may be an option for patients who are difficult to approach endoscopically.

The patient was a female in her 70s. She was brought to an emergency room with epigastric pain. An abdominal ultrasound confirmed gallbladder enlargement and gallbladder wall thickening, and then she was admitted to the hospital with a diagnosis of acute cholecystitis. Contrast-enhanced CT showed poor contrast of the gallbladder wall. Endoscopic ultrasound showed a break in the continuity from the neck of the gallbladder to the cystic duct and a spiral-like structure in the neck of the gallbladder, leading to a preoperative diagnosis of gallbladder torsion. Laparoscopic cholecystectomy released the torsion, and the gallbladder was removed. The patient was discharged from the hospital on the 10^th day. Preoperative diagnosis is important because gallbladder torsion is often associated with necrotizing cholecystitis. Ultrasound endoscopy has a high spatial resolution and is excellent for evaluating the continuity of the cystic duct and spiral structures at the torsion site, we thus report ultrasound endoscopy may be useful in diagnosing gallbladder torsion.

A 75-year-old man who had undergone pancreaticoduodenectomy was admitted for postprandial epicardial pain. Computed tomography revealed an intrahepatic calculus near the site of choledochojejunostomy with intrahepatic bile duct dilation. A short-type single-balloon enteroscope was inserted to the choledochojejunostomy site. After dilating the anastomosis with a 10 mm balloon, the enteroscope was removed, leaving the overtube. An ultra-thin endoscope was inserted through the overtube, was directly advanced into the bile duct, and confirmed the presence of bile duct stone. After electrohydraulic lithotripsy (EHL) was performed, complete stone extraction was performed using the short-type single-balloon enteroscope. The patient was discharged from the hospital with good prognosis and without adverse events. By using the ultra-thin endoscope, a good field of view was secured and EHL could be smoothly performed.