Endoscopic observation of the pharynx should prioritize high-risk patients. Because of complex anatomical structures, such as the tongue and larynx, it is challenging to visualize the entire pharyngeal area in a single view. Therefore, a fixed-point observation method that captures images at predetermined sites during each examination must be employed. The techniques used for observation differ from those for other organs and require methods, such as phonation and the Valsalva maneuver, to thoroughly inspect the mucosal surfaces. Lesions appear similar to that of superficial esophageal cancer and can be diagnosed using image-enhanced endoscopy and magnifying endoscopy.

General anesthesia may cause muscle relaxation during endoscopic treatment, leading to poor visualization. In such cases, devices, such as direct laryngoscopes and mouth gags, are used to secure the endoscopic field. Endoscopic treatments have been developed, with reports of high en bloc resection rates and safety. After endoscopic treatment, surveillance that considers the risk of lymph node metastasis and metachronous cancer is crucial, offering the potential for excellent treatment outcomes.

This article outlines the current state of endoscopic diagnosis and treatment of the pharyngeal region.

Serrated polyposis syndrome (SPS) is characterized by multiple serrated lesions in the colorectum and recognized globally as a high-risk entity for colorectal cancer. The diagnostic criteria were first established by the World Health Organization in 2010 and revised in 2019 to improve clinical validity by excluding diminutive lesions, rectum-predominant cases, and family history as standalone criteria. The etiology of SPS is multifactorial, involving genetic factors, such as ring finger protein 43 mutations, epigenetic alterations mediated by the CpG island methylator phenotype, gut microbiota, and lifestyle influences. Clinically, SPS is strongly associated with colorectal cancer; therefore, complete resection of lesions≥5mm followed by surveillance colonoscopy every 1-3 years is recommended. Besides the serrated pathway, the adenoma-carcinoma sequence has been implicated in tumorigenesis. Future challenges include elucidating the risk of extracolonic malignancies, clarifying familial clustering, identifying genetic backgrounds, and establishing Japan-specific surveillance strategies aligned with international guidelines.

Strongyloidiasis is a parasitic gastrointestinal infection caused by Strongyloides stercoralis. Although often asymptomatic, co-infection with human T-cell leukemia virus type 1 (HTLV-1) or immunosuppression may develop into a severe form known as disseminated strongyloidiasis. Here, we report the case of a 63-year-old man undergoing chemoradiotherapy for lung cancer who presented to the emergency department with generalized weakness and diagnosed with septic shock of unknown origin, prompting antimicrobial therapy. During his clinical course, melena prompted an upper gastrointestinal endoscopy, which revealed edematous duodenal mucosa. Histopathological examination of the biopsy specimens confirmed the presence of Strongyloides stercoralis larvae. It was considered that hyperinfection had developed because of HTLV-1 co-infection and chemotherapy-induced immunosuppression. Based on a diagnosis of disseminated strongyloidiasis, treatment with ivermectin was initiated, leading to clinical improvement and survival until hospital discharge.

An 80-year-old man was admitted to our hospital with sudden hematochezia. Contrast-enhanced CT revealed no bleeding source in the gastrointestinal tract. We suspected a hemorrhagic rectal ulcer and performed colonoscopy after preparatory treatment; however, the source of the bleeding remained unidentified. On day 8, recurrent hematochezia led to shock. A second colonoscopy revealed a pulsatile-exposed vessel in the rectum just above the anal dentate line. Hemostasis was achieved with local injection of HSE and clipping. Dieulafoy-type acute hemorrhagic rectal ulcer can cause hemorrhagic shock and are difficult to detect if the blood pressure is low or bleeding is stable. If a Dieulafoy-type acute hemorrhagic rectal ulcer is suspected, ensuring optimal visualization during endoscopy and selecting an appropriate hemostasis method are crucial.

An 82-year-old man with recurrent cholangitis was admitted to our hospital. Contrast-enhanced CT MRI, and abdominal ultrasonography revealed thickening of the bile duct wall without evidence of malignant or tumorous lesions. IDUS revealed a concentric, uniformly thick, and highly echoic structure in the bile duct lumen. Cytology and biopsy revealed no malignant findings. Suspecting a parasitic cause, extraction was attempted using a retrieval balloon, successfully removing a live fluke, measuring 23mm, was brown, and had a leaf-like morphology. Parasitological identification and serological testing confirmed Fasciola hepatica. This case is valuable because the parasitic organism was successfully removed via endoscopic transpapillary extraction. This case highlights the renewed importance of IDUS for endoscopic evaluation. This study will contribute to future clinical practice and raise awareness regarding fascioliasis as a differential diagnosis for similar cases.

Small-bowel capsule endoscopy (CE) enables visualization of the small-bowel mucosa via ingestion of a capsule-type endoscope. Owing to its minimal invasiveness and high diagnostic accuracy, CE is widely used for evaluating suspected small-bowel bleeding. In January 2021, CapsoCam Plus^Ⓡ, novel CE device with four cameras providing a 360° panoramic view, was introduced in Japan, expanding diagnostic options. Additionally, the device features internal storage, eliminating the need for external transmission during examination and extending battery life compared to conventional CE systems. However, because all images are stored internally, retrieval is mandatory to obtain the recorded data. Further clinical experience and case accumulation are required to clarify the optimal indications and role of this novel CE system compared with existing devices.

Recently, various techniques for mucosal defect closure after ESD have been reported, including clip-assisted approximation. However, a standardized approach has yet to be established. Complete closure remains challenging in cases involving large mucosal defects or thick-walled organs, such as the stomach, in which dead space often results in incomplete closure.

Several suture techniques using nylon threads have been developed to achieve more secure closures. We have reported a novel method focusing on reliable tightening and secure fixation of the closure, called the Clip with Line Pulley Securing (CLiPS) method, which combines nylon threads, endoscopic clips, and a detachable snare or similar device to serve as anchors. The edges were firmly approximated by grasping the mucosal defect margins with clips and applying traction to the thread in a pulley-like manner. Fixation with an anchoring device ensured stable closure. This simple and efficient method allows for single-channel operation without repeated endoscope insertion and removal.

We describe detailed procedures and practical tips for performing the CLiPS method effectively.

Objectives: Surgery is generally the first choice of treatment for gangrenous cholecystitis (GC). However, some patients are not fit for surgery because of their comorbidities. We evaluated the feasibility of endoscopic transpapillary gallbladder drainage (ETGBD) for GC in poor surgical candidates.

Methods: This retrospective study compared the outcomes of ETGBD for acute cholecystitis (AC) with and without complicated GC. Of the 136 patients who underwent ETGBD for AC at a single tertiary referral center between January 2019 and July 2023, 91 who underwent contrast-enhanced computed tomography (CT) before ETGBD were included in the analysis.

Results: Patients were assigned to the GC (n=29) and non-GC (n=62) groups based on CT findings. The technical success rate of ETGBD, clinical success rate for AC, and rate of early adverse events (AEs) in the GC and non-GC groups were 86.2% vs. 91.9% (P=0.63), 79.3% vs. 91.9% (P=0.17), and 27.6% vs. 16.1% (P=0.32), respectively. The technical and clinical success rates were slightly lower, while the early AE rate was higher in the GC group. However, the differences were not significant. The incidence of late AEs was 15.8% in the GC group and 17.9% in the non-GC group, with no significant difference (P= 0.87). Elective cholecystectomy was significantly less frequent in the GC group (P=0.023).

Conclusion: ETGBD is a feasible treatment option for GC in patients contraindicated for surgery