【緒言】膵管内乳頭粘液性腫瘍（IPMN）の手術適応を判断するうえで，壁在結節の血流情報は重要であるが，最適な診断法は確立されていない．本研究は，IPMNの壁在結節に対するDetective Flow Imaging（DFI）を用いた血流診断能を検討した．【方法】2021年4月から2025年5月までに，壁在結節を伴うIPMN外科切除例にDFI-EUSを施行した22例を対象とした．患者背景，画像所見，病理診断結果を後方視的に解析した．【結果】年齢中央値73歳（46-83），女性8例であった．病型は分枝型8例（36％），混合型6例（28%），主膵管型8例（36%）であり，壁在結節長径中央値は5.8 mm（2.1-27 mm）であった．DFI-EUSによる壁在結節の血流検出率は82%（18/22）であった．造影CTは20例に施行され，血流検出感度は35％（7/20）であった．最終病理診断はIPMC 11例，IPMA 11例であり，それぞれの血流検出率はDFI-EUSでIPMC 82％，IPMA 82％，造影CTでIPMC 45％，IPMA 22％であった．【結語】IPMN切除例におけるDFI-EUSは，壁在結節の血流検出率が造影CTと比較して高く，有用な血流診断法であった．一方で，血流の有無のみでは良悪性の鑑別は困難であり，さらなる症例の集積と検討を要する．

82歳女性．Evans症候群に対してプレドニゾロン加療中，4 mg/日に漸減中に肝胆道系酵素と好酸球割合の上昇を認め紹介となった．腹部造影CTと超音波内視鏡では胆管壁の肥厚を認めた．ERCPでは両側肝内胆管が枯れ枝状に狭小化しており，胆道鏡では発赤，浮腫状粘膜及び血管透過性低下を認めた．直視下生検では悪性所見を認めず，胆管への好酸球浸潤を認めたため，好酸球性胆管炎を疑いプレドニゾロンを10 mg/日に増量した．その後肝胆道系酵素は改善し，治療効果判定のERCPでは両側肝内胆管の壁不整は改善し，胆道鏡では正常胆管粘膜を呈し，直視下生検では胆管への好酸球浸潤は消失した．以上より好酸球性胆管炎の診断に至った．胆道鏡による観察と直視下生検は好酸球性胆管炎と原発性硬化性胆管炎，IgG4関連硬化性胆管炎，胆管癌の鑑別に有用である可能性が示唆された．

Purpose: To investigate the clinical features of eosinophilic esophagitis (EoE) among subjects undergoing esophagogastroduodenoscopy (EGD) during medical checkups.

Methods: All subjects undergoing EGD from April 2024 to March 2025 were included. The prevalence of EoE was evaluated. To analyze the risk of EoE, four age and sex-matched normal controls were randomly selected for each EoE case.

Results: Among 11,176 subjects, 38 (0.34%) were diagnosed with EoE. Prevalence of EoE was higher in male (0.43%) than female (0.14%), and in those aged in their 40's and 50's (0.40% and 0.47%, respectively). Allergic diseases and peripheral eosinophilia increased the risk of EoE. Ratio of H. pylori infection was similar in EoE cases and controls.

Conclusion: Prevalence of EoE is 0.34% in the general Japanese population. H. pylori infection, which reportedly reduces the risk of EoE according to previous studies, was not associated in our study.

A man in his 80s presented with severe dysphagia. He had undergone pharyngectomy and reconstruction using pectoral major musculo-cutaneous flap for hypopharyngeal cancer. Postoperatively, appearing stenosis of the pharyngeal flap anastomosis. At our hospital, a small-caliber endoscope was inserted through a gastrostomy and advanced retrogradely to obstruction site. Under rendezvous guidance, the stenosis was incised orally using a high-frequency knife. Although luminal patency was temporally restored, repeated restenosis occurred, and a covered esophageal stent was placed. Then, he was admitted to our hospital with restenosis at the anastomotic site. Using an oral endoscope, the stent was removed and reinserted. We report a case of esophageal stent placement using a rendezvous technique involving both oral and gastrostomy approaches.

Background: Lanthanum carbonate is widely used as a phosphate binder in patients undergoing hemodialysis and is considered safe. However, lanthanum deposition in gastrointestinal mucosa has been increasingly reported.

Case: A man in his seventies undergoing long-term hemodialysis for diabetic nephropathy had been treated with lanthanum carbonate for approximately 13 years. The patient had previously undergone distal gastrectomy for advanced gastric cancer. Follow-up esophagogastroduodenoscopy revealed multiple fine, whitish granular lesions extending from the lesser curvature to the posterior wall of the upper gastric body. Histopathological examination revealed macrophages containing fine brownish granular or crystalline material in the lamina propria. Immunohistochemical staining revealed CD68-positive macrophage aggregation, leading to the diagnosis of gastric lanthanum deposition.

Conclusion: Granular whitish gastric mucosal lesions should be suspected in patients undergoing long-term lanthanum carbonate therapy.

A 64-year-old woman developed dysphagia 24 years after lumpectomy for breast cancer. CT showed thickening of the thoracic esophagus without distant metastases. Endoscopy showed mid-thoracic stenosis, and an endoscopic boring biopsy confirmed esophageal metastasis. PET demonstrated limited bone metastases. Chemotherapy was started after gastrostomy. Esophageal metastasis from breast cancer is rare and often difficult to diagnose because the lesions typically infiltrate the submucosa without mucosal involvement, making superficial biopsies insufficient. This case highlights the importance of considering metastatic disease in patients with a history of breast cancer who present with esophageal stenosis.

Gastritis cystica profunda (GCP) は, 切除後残胃の粘膜下に好発する嚢胞腺増殖を伴う良性病変で, しばしば診断に難渋する. 症例は75歳男性. 食思不振と貧血の精査中に上部消化管内視鏡検査において胃体上部小彎前壁に粘膜内癌を疑う0-IIc病変を認め, 病理学的に高分化型管状腺癌と診断された. ESDを施行したが, 線維化が強く剥離に難渋した. 病理学的には治癒切除であったが, 一方で粘膜下層にGCPの所見を認めた. GCP病変と管状腺癌の間に連続性はなく, MUC5ACおよびMUC6染色を用いて粘液形質を検討したところGCP病変では陽性, 管状腺癌では陰性であった. EUSおよびCT画像においても癌との連続性は認められなかった. 本症例は非切除胃においてGCPを発症した点, 早期胃癌とGCPを併発し両者に病理学的関連性のないことが確認された点において稀有な症例である.

Background: We report three cases of SMT-like gastric cancer ultimately diagnosed using CLEAN-NET.

Cases: All three patients were suspected to have gastric submucosal tumors based on endoscopic findings, and repeated biopsies failed to demonstrate malignancy.

Case 1 endoscopy revealed a reddish elevated lesion with a small ulcerative area, raising suspicion of malignancy despite negative biopsies.

Case 2 involved an enlarging SMT-like lesion accompanied by synchronous superficial gastric cancer treated with endoscopic submucosal dissection.

Case 3 demonstrated gradual tumor enlargement with progression of a delle during follow-up.

CLEAN-NET was performed in all patients for diagnostic and therapeutic purposes. Histopathological examination revealed adenocarcinoma with SMT-like features in all cases. Additional gastrectomy was subsequently performed, and no residual tumor or lymph node metastasis was observed.

Conclusion: CLEAN-NET is a useful and minimally invasive diagnostic and therapeutic option for gastric SMT-like lesions when malignancy cannot be excluded preoperatively.

Submucosal heterotopic gastric glands (HGGs) are benign lesions characterized by ectopic gastric glands in the submucosal layer and may present as submucosal tumor-like lesions. On endoscopic ultrasonography (EUS), HGGs appear as anechoic or hypoechoic areas within the second to third layers and may complicate depth assessment in the presence of gastric cancer.

Herein, we report a case of early gastric cancer with HGG in the anterior wall of the gastric angle. EUS revealed multiple anechoic areas within the second to third layers. Although mucosal cancer was suspected, lymph node enlargement on computed tomography prompted surgery. Histopathological examination revealed adenocarcinoma confined to the mucosa, with a cystically dilated HGG and no lymph node metastasis.

A 26-year-old man with a 4-year history of ulcerative colitis (UC) developed worsening diarrhea followed by epigastric pain, severe nausea, and repeated vomiting. He had previously received mesalazine, corticosteroids, azathioprine, and anti-TNF agents, and was in remission on filgotinib. Esophagogastroduodenoscopy showed diffuse friable erythema and shallow erosions from the gastric fundus to antrum and from the duodenal bulb to the descending duodenum. Biopsies demonstrated marked neutrophilic infiltration with crypt abscesses, consistent with gastroduodenitis associated with UC (GDUC). Colonoscopy confirmed active colitis. Symptoms and inflammation persisted despite supportive therapy. Intravenous risankizumab was started for UC exacerbation, resulting in rapid symptom relief the next day, early resumption of oral intake, and discharge. One-month follow-up endoscopy showed complete mucosal healing, suggesting risankizumab may be effective for GDUC with active UC.

A 64-year-old woman had received long-term treatment with vonoprazan and prednisolone for eosinophilic granulomatosis with polyangiitis. Annual upper gastrointestinal endoscopy for six years revealed multiple fundic gland polyps (FGPs). A polyp in the gastric fornix increased to 15 mm three years earlier, although biopsy findings at that time were benign. At the most recent examination, repeat biopsy revealed adenocarcinoma, and endoscopic submucosal dissection was performed. Histopathological examination demonstrated parietal cell protrusion (PCP), characteristic of long-term proton pump inhibitor (PPI) therapy, along with surface architectural distortion of the foveolar epithelium and irregular glandular structures consistent with well-differentiated adenocarcinoma. Previous reports have described malignant transformation of FGPs associated with long-term PPI use. When an FGP exceeds 10 mm in diameter and presents with central depression, malignant transformation should be considered.

Background: Gastric intramural hematoma is an uncommon gastric wall lesion. Accurate diagnosis is difficult because imaging findings resemble those of submucosal tumors.

Case Presentation: An 83-year-old man who had been receiving edoxaban for atrial fibrillation was admitted with hematemesis. Contrast-enhanced computed tomography revealed an intramural mass in the gastric body with an elevated high-density fluid level in the delayed phase. Endoscopy revealed a submucosal tumorlike protrusion with blood clots. Endoscopic ultrasonography revealed a heterogeneous hypoechoic lesion in the third and fourth layers with pulsatile blood flow on Color Doppler imaging. Emergency distal gastrectomy was performed. Histopathological examination confirmed intramural hematoma with no neoplastic disease.

Conclusions: Endoscopic ultrasonography with Color Doppler imaging is useful for evaluating vascular involvement in bleeding gastric submucosal lesions and selecting an appropriate treatment strategy.

Despite extensive research on early gastric cancer after Helicobacter pylori eradication, knowledge regarding advanced-stage gastric cancer remains limited. We report a case of advanced gastric cancer demonstrating progression during annual surveillance after endoscopic submucosal dissection. A 77-year-old man had a small, reddish lesion in the upper gastric body that gradually enlarged over several years. Repeated biopsies showed no evidence of malignancy until five years later when the lesion developed a submucosal tumor-like elevation with ulceration. Histological examination confirmed adenocarcinoma with malignant ascites, leading to a diagnosis of stage IVB gastric cancer. In conclusion, following H. pylori eradication, gastric cancer may present as a submucosal tumor-like elevation, and its diagnosis using standard forceps biopsies may be difficult.

Accidental ingestion of sharp foreign bodies can cause serious gastrointestinal complications. We report a case who was removed accidentally ingested pushpin embedded in Japanese-style rice cake by esophagogastroduodenoscopy (EGD). An 84-year-old woman accidentally ingested a pushpin together with her medications. Because of discomfort of throat, she swallowed two pieces of Japanese- style rice cake. After that, she visited our hospital Abdominal X-ray and computed tomography showed a pushpin like object in the stomach. Emergency EGD found only multiple Japanese-style rice cakes. We fragmented the Japanese-style rice cakes by a snare and removed the fragmented pieces by a grasper through an overtube. Finally, a pushpin was found and removed. This case illustrates importance of early endoscopic intervention for small sharp foreign body even if embedded in foods.

Case presentation: A 54-year-old man with a history of alcoholic cirrhosis presented to our hospital with hematemesis. Upper endoscopy revealed active bleeding from the gastric varices. Primary hemostasis was achieved with endoscopic variceal ligation (EVL). A second-look procedure revealed rebleeding from the ulcer base after EVL on the sixth day of hospitalization. Re-EVL and radiofrequency coagulation for hemostasis were deemed impractical. Hemostasis was achieved using a MANTIS Clip to invert and suture the ulcer base, then adding a SureClip to completely close the suture of the ulcer base.

Discussion: No effective treatment has been established for rebleeding after EVL of esophagogastric varices. WSB tubes or IVR-based hemostasis may be used when controlling bleeding is difficult. The structure of the MANTIS Clip differs from that of conventional clips, offering superior grasping ability and enabling hemostasis through strong compression. This finding suggests the potential of using the MANTIS Clip as an effective troubleshooting tool for treating postendoscopic rebleeding.

The patient underwent duodenal and biliary stenting for malignant obstruction. Twenty-third days after duodenal stent placement, he developed nausea and vomiting. CT revealed stent fracture with associated gastric outlet obstruction. Endoscopy confirmed that a fractured fragment of the duodenal stent was obstructing the pylorus, which was successfully removed endoscopically. The remaining stent was patent, and no additional intervention was required. Although duodenal stent fracture is a rare complication, it can be clinically significant. In this case, mechanical fatigue from peristalsis near the pylorus was considered a possible cause. This case highlights the importance of being aware of potential stent fracture and the need for careful postoperative monitoring following enteral stent placement.

The case is a male in his 90s with decades-old previous surgery for a hiatal hernia of the esophagus. In 20XX, an esophagogastroduodenoscopy (EGD), peformed due to food transit disturbance and revealed mild esophageal stricture and Long Segment Barrett's Esophagus. Thereafter, periodic EGDs were performed, and, at the 20XX+11 EGD, an elevated lesion was observed on the right anterior side of the lower thoracic esophagus. A biopsy indicated Group 4, and Barrett's esophageal adenocarcinoma was suspected. We performed endoscopic submucosal dissection (ESD). Pathology results were adenocarcinoma, IIa, tub1, pT1a (SMM), INFb, ly0, v0, HM0, VM0.

Barrett's esophageal adenocarcinoma is often difficult to detect in its early stages and may have metastasized when detected. Few reports have described curative resection by ESD of Barrett's esophageal carcinoma detected after a long follow-up, and this case is considered rare.

A 19-year-old man presented with persistent epigastric and left lower quadrant pain. Suspected infectious enteritis was treated conservatively without improvement. Upper gastrointestinal endoscopy on day 7 demonstrated multiple erosions and ulcers in the descending duodenum. Initial biopsy showed only nonspecific inflammation. Serologic testing revealed markedly decreased Factor XIII activity, suggesting vasculitic consumption. On day 12, mild transient purpura appeared on both feet. Retrospective immunohistochemical staining of the duodenal specimens revealed IgA deposition in vascular walls and necrotizing small-vessel vasculitis, confirming IgA vasculitis. Oral prednisolone (40 mg/day) induced rapid remission.

IgA vasculitis should be considered in patients with abdominal pain, duodenal lesions, or reduced Factor XIII activity even in the absence of early cutaneous findings.

Gallstone ileus due to cholecystoduodenal fistula is a rare complication of chronic cholecystitis. We report a case in which fistula formation and subsequent gallstone impaction were suspected based on endoscopic findings.

An 80-year-old man with vomiting and constipation was admitted for surgical treatment of advanced rectal cancer. Laboratory tests revealed renal dysfunction and elevated inflammatory marker levels. Upper gastrointestinal endoscopy performed two weeks before admission revealed a protruding lesion with ulceration in the duodenal bulb. Computed tomography revealed a large gallstone in the gallbladder with suspected duodenal adhesions. On admission, repeat CT revealed a gallstone impacted in the duodenal bulb with marked gastric dilatation. Emergency endoscopy confirmed the presence of an impacted black gallstone; however, endoscopic removal was unsuccessful. The patient underwent duodenotomy for stone extraction and had an uneventful postoperative course.

This case highlights the importance of recognizing biliary enteric fistulas in patients with long-standing gallstones.

A woman in her 40s was was referred for evaluation of a 15-mm submucosal lesion in the transverse part of duodenum, which needed differential diagnosis of a gastrointestinal stromal tumor (GIST). Endoscopic ultrasound (EUS) revealed a 16-mm mass arising from the duodenal submucosa, showing an internal echo pattern similar to pancreatic parenchyma. EUS-guided Tissue Acquisition (EUS-TA) confirmed the mass as heterotopic pancreas, not GIST. Consequently, surgery was avoided, and the patient was conservatively followed. This case show efficacy of accurate preoperative diagnosis by EUS-TA for preventing unnecessary intervention.

Down syndrome is frequently associated with congenital anomalies, among which gastrointestinal disorders are relatively common. Duodenal stenosis and atresia typically present in the neonatal period; however, mild stenosis may remain asymptomatic and undetected until adolescence or adulthood.

We report a case of a 12-year-old boy with Down syndrome who was incidentally diagnosed with congenital duodenal stenosis after foreign body ingestion. He had no history of gastrointestinal disease or symptoms such as vomiting. During hospitalization for pneumonia, an abdominal radiograph incidentally revealed a foreign body. Upper gastrointestinal endoscopy demonstrated a mild, soft membranous duodenal stenosis that impaired distal passage of the foreign body. The endoscope was able to pass through the stenosis, explaining the absence of obstructive symptoms and delayed diagnosis.

This case underscores the importance of considering congenital gastrointestinal anomalies when caring for adolescents and adults with Down syndrome.

Non-contrast computed tomography (CT) performed on a 61-year-old woman presenting with intermittent abdominal pain revealed an ileal intussusception. Colonoscopy performed at the referring clinic revealed no significant findings, and the patient was referred to our hospital. Contrast-enhanced CT revealed a small intestinal intussusception with a fatty nodule at its leading point. Transanal single-balloon enteroscopy revealed a tumor with surface redness and erosion in the terminal ileum. The tumor was prolapsing into the intestinal lumen. After reducing the intussusception, a detachable snare was placed around the long stalk of the tumor. Owing to insufficient ischemia, repeat enteroscopy was performed the following day, during which polypectomy was successfully completed. Histopathological examination confirmed the identity of a 17-mm lipoma. Although most cases of intussusception caused by lipomas are treated via invasive surgery, this case was successfully managed endoscopically.

A 26-year-old man was presented with recurrent abdominal pain and fever of unknown origin. Upper and lower gastrointestinal endoscopy showed no significant abnormalities. However, capsule endoscopy revealed multiple erosions with small elevated lesions extending from the jejunum to the ileum. Double-balloon enteroscopy demonstrated widespread erosive and protruding lesions in the ileum. Genetic analysis identified compound heterozygous MEFV mutations (Exon10 M694I and Exon2 E148Q), leading to a definitive diagnosis of familial Mediterranean fever.

The patient's father also exhibited mild clinical symptoms and carried a MEFV mutation; however, comprehensive gastrointestinal endoscopy revealed no abnormalities. These findings demonstrate intrafamilial heterogeneity in clinical and endoscopic manifestations despite shared MEFV mutations, and highlight the importance of comprehensive endoscopic evaluation for familial Mediterranean fever.

A 69-year-old man presented with chronic watery diarrhea that had persisted since the previous September. Colonoscopy performed in December was unremarkable, and treatment for irritable bowel syndrome was ineffective. He was hospitalized for hypokalemia in February and presented to our hospital for evaluation in March. Blood tests, endoscopy, and abdominal CT were unremarkable. In April, small bowel capsule endoscopy (SBCE) revealed diffuse villous atrophy and granular elevation. Olmesartan-associated sprue-like enteropathy (OAE) was diagnosed and his medication regimen was discontinued. Diarrhea decreased within four days and resolved by day 19. Two months later, follow-up SBCE revealed reversal of atrophy, confirming OAE. Although OAE is a malabsorption syndrome that resolves rapidly after drug withdrawal, its diagnosis is often delayed due to low awareness and long latency. We report a case of OAE that was successfully diagnosed using SBCE.

A 21-year-old woman experienced intermittent abdominal pain for one year. The patient presented with epigastric pain and nausea. Contrast-enhanced abdominal CT revealed small bowel intussusception caused by a polypoid jejunal lesion. As no signs of peritoneal irritation or intestinal necrosis were observed, the patient was managed conservatively. Small bowel endoscopy resulted in spontaneous reduction of the intussusception and identified a 30 mm pedunculated polyp (type Ip) located 20 cm distal to the ligament of Treitz. Given the risk of recurrence, elective polypectomy was performed using single balloon enteroscopy after placement of a detachable snare. The patient showed no features of Peutz-Jeghers syndrome. Histopathology revealed non-atypical glandular epithelium with clear cytoplasm and arborizing smooth muscle bundles, consistent with a Peutz-Jeghers-type polyp.

A 74-year-old woman undergoing follow-up colonoscopy for constipation was incidentally found to have a 10-mm reddish, flat elevated lesion located 10 cm proximal to the ileocecal valve. Magnified narrow-band imaging showed relatively regular vessel and surface patterns, consistent with a JNET Type 2A-like lesion. Biopsy revealed a low-grade intestinal-type adenoma. Considering the need for complete resection, endoscopic submucosal dissection (ESD) was performed. Although technically demanding in the small intestine, stable visualization and maneuverability were achieved. Gel immersion ESD facilitated mucosal incision and careful submucosal dissection. Histopathology demonstrated a high-grade intestinal-type adenoma confined to the mucosa with negative margins. This case suggests ESD is feasible for selected ileal adenomas.

We encountered two cases of submucosal tumor exhibiting an acoustic shadow on colorectal endoscopic ultrasonography. Because neither lesion was able to be diagnosed definitively prior to treatment, endoscopic submucosal dissection was performed in case the leisons were either neuroendocrine tumors or gastrointestinal stromal tumors. Histopathological examination found that both lesions were foreign body granulomas with uniform hyalinization. In retrospect, an acoustic shadow was observed throughout both lesions on endoscopic ultrasonography, a finding atypical of common, neuroendocrine tumors and gastrointestinal stromal tumors, suggesting that this finding may be characteristic of foreign body granulomas with hyalinization or calcification and may serve as a useful clue to the diagnosis of submucosal tumors.

Intestinal spirochetosis is a zoonotic infection caused by Brachyspira aalborgi or B. pilosicoli. It may present with nonspecific abdominal pain or diarrhea and can mimic irritable bowel syndrome. We retrospectively examined nine patients diagnosed with intestinal spirochetosis histopathologically between 2014 and 2024. All patients were middle-aged men, and the condition in 66.7% was incidentally identified in colorectal polypectomy specimens. Endoscopic findings were mostly nonspecific, with mild erythema or edema observed in 22.2% of patients. Five patients received metronidazole or amoxicillin, of whom three (60%) exhibited clinical improvement. Notably, the condition in 77.8% of cases was diagnosed by a single pathologist, suggesting variability in recognition. As spirochetes form a basophilic 2-3 μm fringe along the epithelial surface on hematoxylin and eosin staining, awareness among pathologists is crucial. Intestinal spirochetosis should be considered in patients presenting with irritable bowel syndrome-like symptoms, and active biopsy is recommended for definitive diagnosis.

A 50-year-old woman was diagnosed with pelvic peritonitis and treated with amoxicillin/clavulanate (AMPC/CVA). On the sixth day of therapy, she developed abdominal pain, diarrhea, and bloody stools and revisited our hospital. Abdominal computed tomography revealed wall thickening in the right colon. Colonoscopy revealed edematous stenosis with erythema from the ascending to the transverse colon, accompanied by marked mucosal erythema, intramucosal hemorrhage, and adherent mucus. Stool culture revealed Klebsiella oxytoca; however, drug-induced lymphocyte stimulation test for the suspected antibiotic was negative. Antibiotic-associated hemorrhagic colitis (AAHC) was suspected based on the clinical course, medication history, and characteristic endoscopic findings. Her symptoms rapidly improved after discontinuation of antibiotics. AAHC generally has a favorable prognosis once diagnosed. It is important to consider this condition when diagnosing patients with bloody diarrhea receiving antibiotics.

A 45-year-old man presented with intermittent lower abdominal pain. He was asymptomatic at presentation, and computed tomography (CT) performed two days later revealed intussusception caused by a 6-cm lipoma of the ascending colon. No signs of perforation or bowel obstruction were observed. Although surgical treatment was recommended because of the intussusception, the patient opted for conservative management. One month later, colonoscopy demonstrated a pedunculated lesion with erythema in the ascending colon, markedly smaller than that observed on the initial CT scan. The apex of the lesion was depressed, suggesting spontaneous rupture and shrinkage of the lipoma due to mechanical irritation from intussusception. The patient remained asymptomatic for 6 months. Follow-up colonoscopy revealed further reduction in lesion size to 1 cm, with improvement of erythema. As there was no symptom recurrence or tumor enlargement, periodic colonoscopic surveillance was planned.

Malignant duodenocolic fistula caused by colon cancer is a rare complication that often leads to severe malnutrition and poor condition. Radical surgery is highly invasive and may not be feasible in patients with poor performance status. We report a case of a 73-year-old man with transverse colon cancer complicated by a duodenocolic fistula, who presented with fecal reflux into the upper gastrointestinal tract and severe hypoalbuminemia. Endoscopic examinations revealed a fistula between the duodenum and transverse colon with luminal stenosis. Because surgical treatment and chemotherapy were not feasible, palliative endoscopic treatment was selected. A covered colonic stent was placed to dilate the stenosis and seal the fistula. Following stent placement, fecal reflux disappeared, oral intake improved, and symptoms improved. Covered colonic stenting may be an effective and minimally invasive palliative option for malignant duodenocolic fistula in patients unsuitable for surgery.

An 84-year-old man presented with abdominal pain and diarrhea. Contrast-enhanced computed tomography revealed a target sign in the ascending colon, leading to the diagnosis of intussusception. An emergent colonoscopy was performed to evaluate the etiology and attempt reduction. Although mild mucosal edema was observed in the ascending colon, no persistent intussusception or tumorous lesions were identified. An Anisakis larva penetrating the mucosa of the lower rectum was detected and removed using biopsy forceps. The patient resumed oral intake and was discharged home. Although no Anisakis larva was identified in the ascending colon, transient intussusception triggered by anisakiasis was suspected. While intussusception in adults is most commonly associated with tumorous lesions, anisakiasis should be included in the differential diagnosis. Prompt endoscopic evaluation, careful dietary history taking, and close collaboration with surgeons assist in accurate diagnosis and appropriate management.

A 78-year-old woman with liver cirrhosis was admitted with hematochezia. Colonoscopy revealed rectal varices, and endoscopic variceal ligation (EVL) was performed at a red plug. Post-procedural computed tomography (CT) demonstrated markedly developed rectal varices. The inferior mesenteric vein was dilated, and no other major collaterals were identified, suggesting rapid variceal flow. Endoscopic injection sclerotherapy (EIS) was considered challenging because of the difficulty in retaining the sclerosant and the potential risk of systemic leakage. Balloon-occluded retrograde transvenous obliteration (BRTO) was not feasible because no accessible route was available. Consequently, percutaneous transhepatic obliteration (PTO) was performed. Follow-up CT demonstrated reduced variceal enhancement. This case suggests that PTO is a valuable therapeutic option for rectal varices when endoscopic treatment carries high risk.

Here, we present the case of a woman in her 50s who was hospitalized for ulcerative colitis and dyslipidemia. The patient did not have bowel movement for four days; therefore, elobixibat was administered. After 3 h 30 min, crampy abdominal pain occurred, followed by one bowel movement with hard, watery, and bloody stools. Colonoscopy revealed a longitudinal ulcerative lesion with edema in the sigmoid colon, approximately 25 cm from the anal verge. Histopathological analysis of biopsy specimens revealed ischemic loss of crypts and inflammatory cell infiltration compatible with ischemic colitis. Follow-up endoscopy conducted after one month confirmed an ulcer scar in the sigmoid colon. The patient remains under regular follow-up. Several medications, such as irritant laxative, have been implicated in the development of colonic ischemia. To the best of our knowledge, this is the first reported case of ischemic with elobixibat.

A 72-year-old man with a history of a right renal cyst underwent Endoscopic Mucosal Resection (EMR) for polyps in the transverse and sigmoid colon. The patient developed a high fever the day after the resection. Blood tests revealed elevated levels of inflammatory markers, and computed tomography (CT) revealed the right renal cyst enlargement with wall thickening and increased attenuation of the surrounding fat tissue. Based on these findings, the patient was diagnosed with an infected renal cyst and was admitted to our hospital. The patient was successfully treated with antibiotics and underwent percutaneous cyst drainage. In the present case, mechanical injury to the renal cyst associated with colonic EMR was considered the most likely cause of infection. Infected renal cysts as complications of colonic EMR are extremely rare; therefore, we report the clinical significance of this case.

A man in his 60s presented with constipation, anal pain, and hematochezia. Contrast-enhanced computed tomography showed circumferential wall thickening of the sigmoid colon with marked inflammatory changes in the surrounding mesenteric fat. Barium enema demonstrated a poorly distensible circumferential stenosis of the sigmoid colon. Colonoscopy one month before referral revealed diffusely edematous mucosa with low-profile cobblestone-like elevations, whereas repeat colonoscopy showed well-demarcated ulcerations suggestive of secondary ischemic changes. Conservative management, including fasting and systemic corticosteroid therapy, failed to improve symptoms or imaging findings. Owing to persistent stenosis and refractory symptoms, surgical resection was performed. Histopathological examination revealed diffuse submucosal panniculitis and scattered erosion, suggestive of secondary ischemic mucosal changes. Although the initial endoscopic findings were not diagnostic, serial endoscopic changes clarified progression. This case highlights the importance of assessing treatment response and imaging findings when determining surgical timing in refractory mesenteric panniculitis.

Anorectal malignant melanoma is a rare aggressive neoplasm, and its amelanotic subtype lacks visible pigmentation. Colonoscopy identified a reddish, slightly blackish, elevated 20-mm lesion in the lower rectum. Narrow-band imaging showed an avascular area with dilated vessels. Magnifying endoscopy with crystal violet staining demonstrated a non-structural pit pattern with residual type I pits. Histopathology revealed a submucosal tumor composed of sheets of atypical round to short spindle-shaped cells. Residual crypts corresponded to the endoscopic findings. Immunohistochemistry positive for HMB-45 and S100, with negative Fontana-Masson staining, confirmed amelanotic melanoma. The faint blackish discoloration was attributed to iron-positive pigment associated with intratumoral hemorrhage rather than melanin.

Percutaneous liver biopsy is the standard method for histological diagnosis of diffuse liver diseases; however, endoscopic ultrasound-guided tissue acquisition (EUS-TA) has recently emerged as an alternative. We report a case of autoimmune hepatitis (AIH) diagnosed using EUS-TA with the wet-suction technique. A woman in her 40s presented with fatigue and jaundice. Laboratory tests showed severe liver dysfunction (total bilirubin 5.7 mg/dL, AST 1006 U/L, ALT 1639 U/L), positive antinuclear antibody (1:640), and mildly elevated IgG (1802 mg/dL), while viral hepatitis markers were negative. EUS-TA was performed using a 19-gauge FNB needle primed with heparinized saline. The left hepatic lobe was punctured transgastrically with 20-mL suction and approximately 10 strokes. A specimen with a maximum core length of 11 mm containing four portal tracts was obtained. Histopathology showed interface hepatitis consistent with AIH. No adverse events occurred. Steroid therapy led to rapid improvement in liver function. Wet-suction EUS-TA may be a useful method for obtaining adequate tissue for the diagnosis of diffuse liver diseases.

A 40-year-old man presented with fever and was referred to our hospital. Blood tests revealed elevated hepatobiliary enzymes and inflammatory markers, and contrast-enhanced computed tomography showed a 50-mm liver abscess in segment 8. Abdominal ultrasonography failed to secure a safe puncture route, and a percutaneous approach was considered infeasible. Despite treatment with piperacillin/tazobactam, fever and inflammation persisted. Endoscopic ultrasound-guided liver abscess drainage (EUS-LAD) was performed, and a 10-mm fully covered self-expandable metal stent and coaxial 7-Fr double pigtail plastic stent are placed via the duodenum. Klebsiella pneumoniae was isolated from blood and abscess cultures. Follow-up imaging showed marked reduction of the abscess, then the patient was discharged. The stents were subsequently removed, with no recurrence observed. In this case, EUS-LAD is an effective option for the liver abscess unsuitable for percutaneous drainage.

An octogenarian was admitted with acute cholangitis due to a common bile duct stone. Endoscopic retrograde biliary drainage and antibiotics were initiated on the day of admission, leading to rapid clinical improvement. Stone extraction was subsequently performed using endoscopic retrograde cholangiopancreatography. After an endoscopic sphincterotomy, oozing blood was observed and was refractory to standard endoscopic hemostatic measures. Using a forward-viewing gastroscope, hemostasis was then achieved through the application of Hemospray. Hemospray may serve as a useful rescue option for endoscopic sphincterotomy-related bleeding when conventional hemostatic techniques fail.

An 87-year-old woman developed cholangitis due to stone formation around an internal biliary stent five years after undergoing pancreaticoduodenectomy for distal bile duct cancer. Endoscopic removal using a short-type double-balloon endoscope-assisted ERCP was unsuccessful; however, subsequent percutaneous cholangioscopy with electrohydraulic lithotripsy enabled fragmentation of the stone. The migrated internal biliary stent was then successfully removed using a short-type double-balloon endoscope. This rare case has highlighted the effectiveness of a combined approach using short-type double-balloon endoscopy and percutaneous cholangioscopy for managing postoperative intrahepatic stones associated with a migrated internal biliary stent.

A 74-year-old man presented with fever and abdominal pain. Choledocholithiasis-associated acute cholangitis was diagnosed by laboratory tests and abdominal CT. ERCP was performed. Wire-guided cannulation of the papilla, which was located adjacent to the duodenal diverticulum, was attempted; however, cannulation was achieved only in the main pancreatic duct. An additional papilla, partially concealed by the margin of the diverticulum, was identified on the oral side of the initially cannulated papilla. After cannulation of the second papilla, the common bile duct was successfully accessed, leading to the diagnosis of a double major papilla. This anatomical variant has been reported in approximately 0.18% of ERCP cases. Difficulty in recognizing the biliary opening may prolong the cannulation time and increase the risk of post-ERCP pancreatitis due to repeated pancreatic duct cannulation.

The feasibility and safety of endoscopic ultrasound-guided tissue acquisition (EUS-TA) using a forward-viewing (FV) echoendoscope in cases complicated by gastrointestinal anastomotic stricture are poorly documented.

An 80-year-old man had previously undergone pharyngolaryngoesophagectomy with free jejunal reconstruction. He was suspected of having pancreatic cancer, based on imaging and laboratory findings. We performed EUS-TA using an FV echoendoscope, which offers superior maneuverability and visualization. The echoendoscope was advanced across the anastomotic stricture without difficulty and the procedure was completed safely, without adverse events. Histopathological examination of the obtained tissue confirmed pancreatic adenocarcinoma.

This case demonstrates that the FV echoendoscope is a safe and feasible option for EUS-TA in patients with postoperative anastomotic strictures.

The patient was a 50-year-old man. He was receiving treatment for severe acute pancreatitis, and computed tomography showed the formation of an acute necrotic collection (ANC). Antibiotics were administered; however, the fever did not resolve. Endoscopic ultrasound-guided drainage was performed. A 7 French (Fr) nasal drainage tube and 7 Fr pigtail stent were placed. Because the internal echogenicity was fluid, irrigation with saline was performed using a nasal drainage tube. The patient's clinical symptoms improved after irrigation. ANC shrank without recurrence, and the stent was removed approximately 11 months later. Irrigation is a useful treatment option for infectious ANC.

A man in his seventies presented to our hospital with obstructive jaundice. Contrast-enhanced abdominal computed tomography revealed a unilocular cystic lesion, measuring 53 × 47 mm in the pancreatic head, accompanied by distal bile duct stricture and upstream biliary dilatation. Endoscopic retrograde cholangiopancreatography revealed a smooth stricture of the distal bile duct, suggesting extrinsic compression, and pancreatography demonstrated communication between the main pancreatic duct and the cystic lesion. Thus, based on these findings, biliary and pancreatic duct stents were placed. The biliary stent was subsequently removed after 3 months following improvement of biliary obstruction associated with shrinkage of the pancreatic pseudocyst, without recurrence of jaundice. Overall, this case suggests that pancreatic duct stenting may be an effective treatment option for biliary obstruction caused by pancreatic pseudocysts with pancreatic duct communication.

EUS-guided cyst drainage (EUS-CD) is commonly selected for infectious peripancreatic fluid collections (PFCs) when conservative treatment, such as antibiotics therapy, fails to achieve clinical improvement. Although the interventional procedures are generally recommended after four weeks, when encapsulation is considered mature, recent reports have demonstrated the effectiveness of earlier intervention depending on the patient's systemic condition. Here, we report a case in which EUS-CD was performed for an infectious PFC approximately one week after onset, resulting in a favorable clinical outcome.