【背景】胃食道接合部（GEJ）は，胃内容物の逆流を防ぐ解剖学的要素から構成される．本研究では，胃食道逆流防止機構（Anti-reflux barrier：ARB）を動的に評価する新たなPhase conceptを考案し，各Phaseの所見を解析した．【方法】2024年2～4月に，内視鏡的内圧測定統合システム（EPSIS）を施行した胃食道逆流症状のない患者を対象に後ろ向き単施設研究を実施した．ARBの動態をPhase I（胃相），Phase II（LES相），Phase III（食道クリアランス相）に分類し，EPSISで測定した胃内圧（IGP）とARBの形態変化を評価した．【結果】対象30例の年齢中央値は58歳（IQR：46.5-68.8歳），男性20名，女性10名であった．Phase Iでは低圧（中央値6.75 mmHg）で80%の症例に噴門粘膜唇と小彎の縦襞を認めた．Phase IIでは中圧（中央値11.8 mmHg）で86.7%にScope holding sign（SHS）を確認した．Phase IIIでは高圧（中央値19 mmHg）によりSHSが解除され，80%で食道蠕動運動が観察された．【結語】Phase conceptは，胃食道逆流防止機構の動的変化を理解する新たな手法となる可能性がある．今後，逆流症状を有する症例での検討や他のモダリティとの相関解析が必要である．

【目的】近年，鎮静剤を用いた内視鏡診療の需要が高まっているが，重篤な偶発症のリスクを伴うため，安全な周術期管理が不可欠である．当院では2021年に「鎮静の安全な実施のためのワーキンググループ（以下WG）」を多職種・多診療科で発足した．今回その取り組みと効果について検証した．【方法】WG発足前後での鎮静剤の使用状況および偶発症の発生状況を比較検討した．【結果】WGの主な取り組みは，院内ガイドラインの作成，全身麻酔管理対象症例の明確化，院内教育体制の構築，プロポフォール使用認定制度の導入，プロポフォール使用プロトコルの作成，鎮静剤使用および偶発症の全数把握と検証である．WG発足前の2019年における内視鏡室でのプロポフォール使用件数は9件，ミダゾラム使用件数は2172件であり，鎮静処置時に重篤な偶発症を1件認めた．一方，発足後の2023年にはプロポフォール使用件数が222件，ミダゾラム使用件数が3850件となり，軽微な偶発症（SpO₂＜90％）をプロポフォールで4件，ミダゾラムで9件認めたが，重篤な偶発症は発生しなかった．また，麻酔科管理下で手術室にて行われたESD治療件数は，2019年の73件から2023年には94件に増加していた．【考察】WGの取り組みにより，内視鏡室でのプロポフォールを用いた鎮静が安全に実施されていることが確認された．

【背景】上部消化管内視鏡検査（EGD，Esophagogastroduodenoscopy）の本邦での75歳以上の後期高齢者の割合は増加している．高齢者は併存疾患も多く，鎮静剤を用いるEGDには慎重な対応が求められる．【目的】後期高齢者に対する当院の外来・入院EGDの鎮静の現状を明らかにする．【方法】2022年7月から翌年6月に外来・入院EGDを施行した75歳以上の患者を対象とし，患者背景，検査背景，退出遅延割合，偶発症を検討した．検査後プロポフォール・塩酸ペチジン使用時は30分，ミダゾラムは1時間を基本とした休憩を行い，意識レベル，運動機能，呼吸循環状態に基づいた退室基準を満たすことを確認し帰宅・帰室とした．退出基準を満たさず休憩延長となったものを退出遅延と定義した．退出遅延のリスク因子に関し多変量解析を行った．【結果】検討対象は2253名，2826件．年齢中央値は79歳，検査目的は術前精査，スクリーニング，サーベイランスが405，1717，704件．鎮静・鎮痛剤使用割合は全検査の41％，退出遅延割合は鎮静・鎮痛剤使用例の13.1％．退出遅延のリスク因子は女性・ミダゾラム・2剤併用であった．入院を要した偶発症は2例であった．【結論】後期高齢者に対するEGDは鎮静・鎮痛剤による偶発症が一定の割合で起こることに留意し，鎮静の適応や薬剤の種類，容量を検討すべきである．

【緒言】治療困難結石として，巨大結石や積み上げ結石，3管合流部結石などが挙げられるが，拡張した総胆管内に浮遊する小結石も除去に難渋する事を経験する．今回，除去困難であった小結石に対し，胆道鏡直視下リトリーバルバスケットが有用であった3症例を経験したので報告する．

【症例1，2】症例は積み上げ結石症例と多発小結石症例．通常法で小結石除去を試みたが困難だった．後日，胆道鏡直視下リトリーバルバスケット用いて，結石除去に成功した．

【症例3】73歳，女性．腹腔鏡下胆嚢摘出術時胆管損傷により胆管空腸吻合術R-Y再建の既往あり．左管内胆管結石除去目的にシングルバルーン内視鏡でのERCPを行った．細径9 Fr胆道鏡を使用．EHLで結石破砕を行い，胆道鏡直視下リトリーバルバスケットを用いて結石除去に成功した．

An 87-year-old man with dysphagia was diagnosed with esophageal adenocarcinoma. Endoscopic examination revealed a 15-mm, erythematous elevated lesion in the cervical esophagus continuous with the ectopic gastric mucosa. Neither computed tomography nor 2-fluoro-2-deoxy-D-glucose-positron emission tomography revealed signs of lymph node or distant metastasis. Owing to the patient's advanced age, endoscopic submucosal dissection (ESD) under general anesthesia was performed for local control. Immunohistochemical examination revealed sal-like protein 4 (+), alpha-fetoprotein (AFP) (+), glypican-3 (+), and hepatocyte paraffin 1 (-), confirming the diagnosis of AFP-producing adenocarcinoma. This report describes an extremely rare case of ESD for AFP-producing adenocarcinoma arising from the ectopic gastric mucosa.

An 84-year-old woman diagnosed with esophageal small cell carcinoma through endoscopic biopsy was referred to our hospital. Conventional endoscopy revealed a 25 mm 0-IIc lesion with unclear margin on the right wall of lower esophagus, and NBI magnification confirmed Type B1 esophageal cancer as per Japanese classification. Re-biopsy showed small cell carcinoma with 100% Ki67 index. The lesion was diagnosed as esophageal neuroendocrine carcinoma, and magnified endoscopy predicted the invasion depth as cT1a. Considering the age of the patient, the lesion was resected en bloc with ESD. Pathological findings showed a 25 × 18 mm tumor mass with invasion into lamina propria mucosae (LPM), no lymphovascular invasion, and negative horizontal and vertical margin.

The detection of early stage esophageal neuroendocrine carcinoma is extremely rare, and no report has described magnified endoscopic findings so far. We report our findings herein along with a review of literature.

A 62-year-old man was referred to our department for evaluation of an intra-abdominal cyst detected during a routine health check. Computed tomography showed a unilocular, homogeneous cyst adjacent to the pylorus. Upper gastrointestinal endoscopy and endoscopic ultrasound revealed a cystic lesion located outside the fourth layer of the gastric wall. Based on these findings, a diagnosis of a gastric duplication cyst was made, and surgical resection was performed because of the risk of malignancy. Histopathological analysis revealed a single layer of columnar epithelium lining the cyst, which was located in the subserosal tissue. Although gastric duplication cysts are often asymptomatic, their risk of malignancy increases with size. Therefore, surgical resection should be considered when such cysts are identified. Accurate diagnosis and management rely on thorough evaluation with imaging modalities.

A patient with a past history of Helicobacter pylori (H. pylori) eradication undergoes routine esophagogastroduodenoscopy (EGD). EGD revealed a 10 mm discolored, slightly elevated lesion in the corpus of the stomach. Endoscopic biopsy confirmed a diagnosis of adenocarcinoma of the fundic gland type and ESD was performed.

The final pathological diagnosis was adenocarcinoma of the fundic gland type, pT1a (M), pUL0, Ly0, V0, pHM0, pVM0.

Gastric adenocarcinoma of the fundic gland type is considered one of the H. pylori uninfected gastric carcinomas, but cases with current infection or after eradication are also seen in some cases. It is important to perform EGD while examining the characteristics of this lesion.

We report cases of gastric mucosa-assisted lymphoid tissue (MALT) lymphoma caused by Non-Helicobacter pylori Helicobacter (NHPH). Case 1: A male in his 60s underwent an endoscopic examination that revealed a faded depressed surface in the hypogastric fold. Histological analysis established a diagnosis of MALT lymphoma. PCR test was positive for H. heilmannii (s. s.) and negative for H. pylori. Endoscopic findings improved with eradication, and the histology of MALT lymphoma disappeared. Case 2: A 60s woman was diagnosed with gastric MALT lymphoma. PCR test was positive for H. suis and negative for H. pylori. Endoscopic findings did not resolve the MALT lymphoma findings after eradication. The addition of radiotherapy resulted in the disappearance of both endoscopic and histological findings of MALT lymphoma.

A 50-year-old woman presented with lower abdominal bloating. Upper endoscopy and contrast-enhanced computed tomography (CT) suggested scirrhous gastric cancer. Gastric biopsy revealed atypical cell proliferation; however, no atypia was observed in the gastric mucosal epithelium. The atypical cells exhibited relatively uniform growth, raising suspicion of metastasis. Considering her age and gender, breast cancer was suspected. Immunohistochemistry revealed E-cadherin negativity and estrogen receptor positivity, consistent with invasive lobular carcinoma. A breast needle biopsy confirmed these findings, leading to a diagnosis of gastric metastasis from breast cancer. Here, we report a case in which gastric metastasis was detected before the primary breast cancer.

A 66-year-old female patient presented with hematemesis. Esophagogastroduodenoscopy (EGD) revealed a 30 mm solitary polyp in the middle part of the stomach. The bleeding source was not identified. Contrast-enhanced CT showed a 30 mm mass in the stomach. The area surrounding the mass was well enhanced in the arterial phase, suggesting possible bleeding from this area.

The next day, the patient again had hematemesis, and EGD was performed, but the findings remained unchanged. Since the polyp was suspected as the source of bleeding, endoscopic mucosal resection was performed for both diagnosis and treatment. Pathological examination confirmed the diagnosis of hamartoma.

Since then, the patient has had no recurrence of hematemesis. Gastric hamartoma with hematemesis is rare. Here, we report a case of gastric hamartoma diagnosed based on hematemesis as the initial symptom.

We present the case of a man in his sixties experienced pain in his oral cavity and pharynx. The following day, he experienced epigastric discomfort, increased belching, and flatulence, leading to a visit to our hospital. Esophagogastroduodenoscopy revealed diffuse white granular elevations in the gastric body and fundus. On a magnified endoscopic view, the white granular elevations displayed a central depression in their apex. We initiated symptomatic therapy with mosapride citrate. Histopathological analysis of biopsy specimens from the white granular elevations revealed infiltration of more than 100 eosinophils per high-power field, leading to a diagnosis of eosinophilic gastritis. A follow-up endoscopy conducted 3 months later confirmed the complete resolution of the white granular elevations in the gastric body and fundus. The patient remains under regular follow-up.

An 87-year-old man was found to have a subepithelial lesion (SEL) in the gastric antrum by esophagogastroduodenoscopy (EGD) performed at another hospital, following which he was referred to our institute for further examination and treatment. EGD revealed a tumor extending from the anterior wall of the gastric antrum into the duodenum. Endoscopic ultrasound showed a hypoechoic mass originating from the third layer, with a heterogeneous interior and well-defined borders. Based on these findings, we diagnosed the lesion as a gastrointestinal stromal tumor (GIST) and planned treatment due to the potential risk of ball valve syndrome. Considering the patient's background, endoscopic submucosal dissection (ESD) was performed under general anesthesia.

This report presents a case of gastric GIST successfully treated with ESD.

We report the case of a 70-year-old woman who underwent breast-conserving surgery for right breast cancer. Fourteen years after surgery, elevated CA15-3 levels were detected. A PET/CT scan revealed enhancement in the gastric body, and esophagogastroduodenoscopy showed mild edema and erosions throughout the gastric body. These findings didn't resemble the typical mucosal pattern of gastric cancer. A biopsy of the lesion revealed adenocarcinoma with signet-ring cells, and immunohistochemistry confirmed ER and GATA3 positivity, consistent with gastric metastasis from breast cancer.

The patient was treated with Chemotherapy leading to an initial improvement in endoscopy findings. However, it was discontinued after four months due to drug-induced pneumoniae. Then breast cancer progressed, and erosion worsened.

This case highlights the importance of endoscopic and histopathological evaluation, for the accurate diagnosis of gastric metastasis from breast cancer.

A 90-year-old man was referred to our hospital for researching anemia and duodenal tumor. Computed tomography showed circumferential wall thickening from duodenal descending part to jejunum. Upper gastrointestinal endoscopy revealed multiple submucosal tumor-like protrusions attached fresh blood from duodenal descending part to duodenal horizontal part. A duodenal biopsy revealed amyloid deposition in the lamina propria mucosa. These findings were consistent with amyloidosis. Additionally, there were no underlying disease and other organ failure. Considering characteristic endoscopic findings, we diagnosed this patient as primary AL amyloidosis. Symptoms with anemia improved by transfusion and iron supplement. Gastrointestinal amyloidosis is a rare disease. It is very important to remember gastrointestinal amyloidosis from characteristic endoscopic findings and computed tomography. In that case, you had better perform the biopsy from the characteristic lesion.

A 75-year-old man with a history of prostate cancer, treated with orchiectomy, androgen deprivation therapy, and radiation, was found to have multiple para-aortic lymph node swellings on MRI. Serum tumor markers related to prostate cancer were negative. Follow-up MRI demonstrated progression of the lymphadenopathy. PET-CT showed intense FDG uptake in the para-aortic and pelvic lymph nodes, without involvement of the prostate. Laboratory tests revealed elevated levels of carcinoembryonic antigen (CEA) and soluble interleukin-2 receptor (sIL-2R), leading to a referral for tissue diagnosis.

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed on the para-aortic lymph nodes using a GF-UCT260 echoendoscope. Histopathological examination of the specimen confirmed lung adenocarcinoma. Subsequent CT identified a 7 mm nodule in the right upper lobe, which was diagnosed as primary right upper lobe lung adenocarcinoma (cT1aN0M1c, Stage IVB).

To our knowledge, this is the first reported case of lung adenocarcinoma diagnosed via EUS-FNA of abdominal lymph nodes. This case highlights the utility of EUS-FNA in identifying extrapancreatic and extrapulmonary malignancies involving abdominal lymphadenopathy.

We report a case of endoscopic placement of a covered duodenal stent for the obstruction of the uncovered duodenal stent. An 80-year-old woman was admitted with a chief complaint of vomiting. Abdominal contrast-enhanced computed tomography revealed local recurrent breast cancer lesions in the right breast, multiple bone metastases in thoracolumbar spine, and stenosis of the horizontal duodenum due to peritoneal dissemination. An uncovered duodenal stent was placed to reduce the risk of pancreatitis due to compression of the duodenal Vater papilla. 23 days later, she was admitted with vomiting and was diagnosed with stent obstruction due to tumor growth in the stent. She was willing to eat, and a 12-cm-long covered duodenal stent (diameter, 22 mm) was placed using the stent-in-stent technique. The patient has not experienced re-occlusion or stent migration at last follow-up. The choice between uncovered and covered stents remains controversial. Future studies should evaluate approaches to overcome tumor growth in the stent and stent migration to improve stent patency.

A woman in her 70s was hospitalized because of vomiting and an inability to consume food. Dehydration and atrial fibrillation associated with tachycardia were observed. Computed tomography revealed food obstruction in the duodenum. The patient's general condition improved after admission, and on the second hospital day, the food bolus in the duodenum was removed endoscopically. The removed food was subsequently introduced into the stomach. A liquid diet was started on the fourth hospital day, but food obstruction in the duodenum recurred on the same day. On the fifth hospital day, the food bolus was again endoscopically removed from the duodenum. The removed food particles were introduced into the stomach and then removed from the body, excluding extremely small particles. After the second endoscopic treatment, the patient was fed and discharged on the 20th hospital day, and no recurrence has been observed subsequently.

A man in 50s with a history of Helicobacter pylori eradication therapy was taking loxoprofen daily without a proton pump inhibitor and was admitted to the hospital with abdominal pain and tarry stools. Esophagogastroduodenoscopy revealed duodenal ulcer scars, a shallow ulcer in the postbulbar duodenum, and a strictured superior duodenal angulus, which was impassable with the scope. Because other conditions such as intestinal tuberculosis and Crohn's disease were ruled out, the stricture was presumed to have resulted from repeated ulcer remissions and flare-ups due to nonsteroidal anti-inflammatory drug use. After initiation of proton pump inhibitor therapy, endoscopic balloon dilation was performed on the stricture. The patient was subsequently able to resume eating. No stricture was observed on esophagogastroduodenoscopy 3 months after endoscopic balloon dilation, indicating its effectiveness for benign duodenal stenosis.

A male in his 60s had an upper gastrointestinal endoscopy (EGD) in January 20XX−3 that revealed a 5 mm-sized submucosal tumor in the anterior wall of duodenal bulb, and EMR-O was performed in April of the same year for diagnostic purposes. The resection fragment had spindle-shaped cell proliferation and was considered to be a fibroblast. After EGD in November 20XX−1, he was admitted to the hospital in March 20XX for removal of the residual Over-The-Scope Clip (OTSC), as he had complained of abdominal discomfort. After admission, the OTSC was cut and retrieved using the rem OVE system. The patient was discharged on the third day without complications. After removal of the clip, abdominal discomfort disappeared. The remOVE system was effective in our patient.

A 63-year-old man with peritoneal dissemination of pancreatic tail cancer after stent placement in the descending colon was admitted due to persistent vomiting. CT scan revealed gastrointestinal obstruction was caused by invasion of the pancreatic tail cancer near the Treitz ligament. Stent placement was attempted using short single-balloon enteroscopy (sSBE). Although sSBE reached near the Treitz ligament, the lumen of the stenosed area could not be visualized due to the angulation. Later, after placing a sliding tube into the duodenum using sSBE, an ultra-thin scope was inserted, allowing the identification of the stenotic lumen. After placing a guidewire in the small intestine, sSBE was reinserted, and a gastrointestinal stent was placed. In this case, the procedure was completed using a combination of sliding tube and ultra-thin scope.

A female in her 80s underwent mastectomy and axillary dissection (III) for a right invasive lobular carcinoma. Three months later, recurrence was observed in the chest wall and lymph nodes, and the patient underwent resection. Treatment with TS-1 was continued, but it was discontinued after approximately one year, at her request. Two months later, the patient presented to the emergency department with a chief complaint of repeated vomiting. Computed tomography (CT) of the abdomen revealed stenosis from the fourth segment of the duodenum to the proximal jejunum, and upper gastrointestinal endoscopy revealed circumferential wall thickening in the fourth segment of the duodenum. Biopsy results revealed a histological pattern consistent with invasive lobular carcinoma, and the patient underwent laparoscopic gastrojejunal bypass surgery. Intra-operative findings revealed a small intestinal metastasis of invasive lobular carcinoma. The patient was discharged from the hospital within two weeks, but her general condition gradually worsened, including peritoneal dissemination, and she died at home approximately one month post-diagnosis.

We report a case proximal release-type colonic stent for malignant rectal obstruction. The proximal release-type colonic stent showed good result of decompression for lower rectal obstruction close to the dentate line. Further studies are warranted to investigate the new stent's efficacy and indications.

We report eight cases of the endoscopic covered colonic stenting for the obstruction of the colonic cancer. Covered colonic stent is effective and safe for the obstruction of the colonic cancer.

A 19-year-old man visited our clinic with chief complaints of fever and diarrhea. Computed tomography revealed edematous wall thickening. Coloscopy indicated continuous circumferential edematous mucosa with irregular erosion. Although ulcerative colitis (UC) could not be ruled out, large intranuclear inclusions and anti-cytomegalovirus (CMV) antibody-positive cells were noted. Additionally, blood tests were positive for C7HRP and CMV-IgM with a high titer. Based on these findings, CMV enteritis due to the initial infection was diagnosed. Despite conservative treatment, edematous mucosa and anti-CMV antibody-positive cells persisted. Consequently, valganciclovir treatment was initiated. However, follow-up endoscopic findings showed no improvement. Given these findings, the patient was ultimately diagnosed with UC as the initial manifestation, complicated by CMV enteritis due to primary infection.

A woman in her 60s underwent lower gastrointestinal endoscopy for positive fecal occult blood testing. A circumferential laterally spreading tumor (LST) was found from the rectum to the sigmoid colon, and endoscopic submucosal dissection (ESD) was performed. Pathology confirmed a 160×95 mm intramucosal carcinoma with curative resection, and the patient was discharged on postoperative day 5. To prevent stricture, a local steroid injection was administered the day after ESD. At 2 and 6 weeks post-ESD, the patient was asymptomatic. However, at 12 weeks, defecation difficulty occurred, and endoscopy revealed a stricture. Balloon dilation relieved symptoms, but recurrence at 15 weeks required a second dilation. The patient has since remained asymptomatic. This case illustrates stricture formation after circumferential rectal ESD despite steroid use, raising questions about the efficacy of steroid injections in preventing scarring.

A 4-year-old girl presented with intermittent hematochezia. Abdominal ultrasonography revealed a 40 mm pedunculated mass with abundant blood flow at the hepatic flexure, leading to a diagnosis of intussusception caused by a polypoid lesion. The intussusception was successfully reduced via hydrostatic enema. Colonoscopy under general anesthesia revealed a 45 mm pedunculated polyp with an irregular, reddish surface. En bloc resection was performed using snare polypectomy. Pathological examination confirmed a juvenile polyp. The patient recovered without complications and was discharged on day 7. This case highlights the importance of anesthesia management and appropriate scope selection, for safe and effective endoscopic polypectomy in pediatric patients with large polyps.

The patient was a 76-year-old woman. She had been undergoing periodic enteroscopy at another hospital. She was referred to our department for CS. When CS was performed at our hospital, a flat lesion with a yellowish-white color and a diameter of 20 mm was observed on the anterior wall of the lower rectum within 8 cm of the anal verge. NBI of the same area showed that the existing honeycomb network was still present, and a whiteish deposit was clustered in the subepithelium. A biopsy was performed to confirm the presence of subepithelial deposits. Pathological examination revealed infiltration and aggregation of macrophages phagocytosing granular crystals, leading to the diagnosis of barium granuloma.

The patient was a 77-year-old man who developed jaundice 2 weeks ago. Abdominal CT revealed the dilatation of the right and left intrahepatic bile ducts caused by hilar cholangiocarcinoma, prompting ERCP. Cholangiography revealed stenosis of the hilar bile duct, but guide wire (GW) seeking to the dilated bile duct was challenging, resulting in the placement of a 5 Fr 8 cm double pigtail stent in the B4a and B4b ducts, respectively. Because the reduction in jaundice after stent placement was minimal, a three-dimensional hologram was created from the Drip Infusion Cholangiography CT image data using Holoeyes MD. This allowed the operator and assistant to stimulate an approach to the left bile duct, leading to repeat ERCP. This time, GW was successfully placed in B8 and B1, with a 5 Fr 8 cm double pigtail stent inserted into each. The use of extended reality appeared beneficial for achieving selective bile duct drainage in patients with hilar cholangiocarcinoma.

An 87-year-old female patient presented with hematochezia. Clinical examination revealed an elevated, erythematous lesion on the perianal skin. Imaging studies, including computed tomography, showed edema of the rectal mucosa with enlargement of the regional lymph nodes, particularly the left inguinal and aortic nodes. Colonoscopy revealed a 20 mm high lesion on the rectal mucosa, which was not in continuity with the perianal lesion. Histopathological analysis of both the perianal skin and the rectal biopsy confirmed the diagnosis of colorectal cancer, with subsequent identification of pagetoid spread from the rectal malignancy. Differentiating between perianal Paget's disease and pagetoid spread originating from nearby carcinomas is a diagnostic challenge, and the use of immunohistochemical staining is proving to be an invaluable adjunct. In the presence of perianal mucosal lesions, colonoscopy is strongly recommended to assess the potential for pagetoid spread from other primary sites.

A 16-year-old male after surgery for congenital biliary dilatation was admitted to our hospital with bile duct stone cholangitis. Our primary treatment option was endoscopic procedure using single-ballon endoscopy. However, it was challenging to reach the hepaticojejunal anastomosis, because the surgical record was lost. In our case, we successfully performed a hybrid endoscopic treatment in which a 12-mm port was inserted into the postoperative bowel under a small laparotomy, followed by endoscopic treatment. His postoperative course was satisfactory, and he was discharged six days after surgery. This treatment method may be an alternative approach when less invasive treatment is favoured and endoscopic procedures are difficult to implement.

A 69-year-old man underwent endoscopic bile duct stone removal and bile duct stent placement for common bile duct and gallbladder stones in 2020. CT showed residual bile duct stent and stones around the stent, leading to a diagnosis of cholangitis due to bile duct stones. Endoscopic retrograde cholangiopancreatography (ERCP) was performed, the stent was torn during attempts at removal. After another attempt to remove the stones was unsuccessful, extracorporeal shock wave lithotripsy (ESWL) was performed. However, stone removal proved difficult, and electronichydraulic lithotripsy (EHL) was performed. The stone was successfully crushed, and the stone was removed along with the stent. The stone and granulation were adherent to the stent.

Stones forming around a long-implanted bile duct stent are a rare complication called stent-stone complex (SSC). In this report, we describe a case of SSC that was difficult to remove endoscopically, and review related literature.

An 80-year-old female experiencing a loss of appetite was referred to our hospital. Drug-induced hypercalcemia was suspected as a possible cause. There was a persistent increase in unexplained inflammatory response and fever, resulting in the initiation of ceftriaxone (CTRX) treatment.

Subsequently, although her symptoms improved, blood tests revealed increased liver and biliary enzyme levels, and abdominal CT tomography revealed gallbladder and common bile duct stones. As the same findings were not observed on abdominal CT at the time of admission, ceftriaxone-related pseudolithiasis was suspected.

Due to the presence of cholangitis, endoscopic retrograde cholangiopancreatography, biliary stone extraction, and drainage were performed. Based on the clinical course, a high possibility of CTRX-associated pseudolithiasis was considered.

Endoscopic retrograde cholangiopancreatography (ERCP) is often difficult to perform after gastrectomy. Recently some cases have been reported that used a multibending scope (M-Scope, GIF-2TQ260M, Olympus Corp., Tokyo, Japan). The M-Scope has two independent bending points that allow the duodenal papilla to be viewed in a suitable position for cannulation. The scope also has dual working channels that each can be manipulated independently. In this case, one channel of the scope was used to insert a guidewire into the pancreatic duct to hold the papilla, and the other channel was used to try to insert a catheter into the bile duct. As a result, this method allowed us to cannulate to the bile duct easily.

A 70s-year-old woman with acute cholecystitis was admitted to our hospital. Computed tomography (CT) revealed a cystic lesion in the tail of the pancreas. Post-cholecystectomy, dynamic CT revealed a 27 mm cystic lesion with a thickened, contrast-enhanced wall. Magnetic resonance imaging confirmed a unilocular lesion with no diffusion restriction. Endoscopic ultrasonography demonstrated a cystic lesion without a "cyst-in-cyst" appearance. Endoscopic retrograde pancreatography did not reveal mucin in the pancreatic duct or communication with the lesion. The preoperative differential diagnoses included a mucinous cystic neoplasm or cystic degeneration of a solid tumor. The patient underwent distal pancreatectomy. Histopathological examination confirmed the lesion as a simple mucinous cyst (SMC), lacking ovarian-like stroma and with gastric-type mucinous epithelium. SMC is challenging to diagnose pre-operatively, but it is crucial to differential diagnoses. SMC shares mucinous features with branch-duct intraductal papillary mucinous neoplasm (BD-IPMN); therefore, further investigation into its potential association with pancreatic cancer is warranted.

A 64-year-old man was admitted with acute pancreatitis. On the 29th day of hospitalization, an abdominal computed tomography (CT) scan revealed infected walled-off necrosis, prompting endoscopic ultrasound-guided drainage through the stomach.

Subsequently, multiple necrosectomies were performed using both endoscopic and percutaneous drainage as part of a step-up approach. Nine months after the onset of pancreatitis, contrast imaging was performed via an external fistula in the right lower abdomen to evaluate the fistula and attempt closure with endoscopic clipping. However, 10 days after clipping, contrast leakage into the duodenum was observed again when fluid passed through the external fistula. The fistula was then successfully ligated using an over-the-scope clip (OTSC) with the suction method. Following OTSC placement, the fistula was effectively sealed, and the right lower abdominal abscess showed significant improvement.

A 71-year-old man presented with pancreatic cancer. Disease was suspected based on ultrasound findings during a health examination. CT showed dilatation of the main pancreatic duct at the pancreatic tail, stenosis of the main pancreatic duct, and atrophy of the pancreatic body. Magnetic resonance imaging (MRI) revealed stenosis of the main pancreatic duct and several small cystic lesions in the pancreatic body. Endoscopic ultrasound did not identify a pancreatic tumor; thus, fine-needle aspiration could not be performed. Therefore we performed serial pancreatic juice aspiration cytological examination and the pancreatic juice cytology yielded a diagnosis of adenocarcinoma. Based on the diagnosis of pancreatic body cancer, we performed subtotal stomach-preserving pancreaticoduodenectomy. Histopathological findings revealed pancreatic body cancer (T1 N0 M0).