Comparison of the Ability of Artificial-Intelligence-Based Computer-Aided Detection (CAD) Systems and Endoscopists to Detect Colorectal Neoplastic Lesions on Endoscopy Video.

Artificial-intelligence-based computer-aided diagnosis (CAD) systems have developed remarkably in recent years. These systems can help increase the adenoma detection rate (ADR), an important quality indicator in colonoscopies. While there have been many still-image-based studies on the usefulness of CAD, few have reported on its usefulness using actual clinical videos. However, no studies have compared the CAD group and control groups using the exact same case videos. This study aimed to determine whether CAD or endoscopists were superior in identifying colorectal neoplastic lesions in videos. In this study, we examined 34 lesions from 21 cases. CAD performed better than four of the six endoscopists (three experts and three beginners), including all the beginners. The time to lesion detection with beginners and experts was 2.147 ± 1.118 s and 1.394 ± 0.805 s, respectively, with significant differences between beginners and experts (p < 0.001) and between beginners and CAD (both p < 0.001). The time to lesion detection was significantly shorter for experts and CAD than for beginners. No significant difference was found between experts and CAD (p = 1.000). CAD could be useful as a diagnostic support tool for beginners to bridge the experience gap with experts.

Safe and Efficient Procedures and Training System for Endoscopic Submucosal Dissection.

Recent improvements in endoscopists' skills and technological advances have allowed endoscopic submucosal dissection (ESD) to become a standard treatment in general hospitals. As this treatment entails a high risk of accidental perforation or hemorrhage, therapeutic procedures and training methods that enable ESD to be conducted more safely and efficiently are constantly being developed. This article reviews the therapeutic procedures and training methods used to improve the safety and efficiency of ESD and describes the ESD training system used in a Japanese university hospital at which the number of ESD procedures has gradually increased in a newly established Department of Digestive Endoscopy. During the establishment of this department, the ESD perforation rate was zero among all procedures, including those conducted by trainees.

Comparative study between histochemical mucus volume, histopathological findings, and endocytoscopic scores in patients with ulcerative colitis.

Ulcerative colitis (UC) causes a reduction in goblet cells. However, there have been few reports on the relationship between endoscopic and pathological findings and mucus volume. In this study, we quantitatively evaluated histochemical colonic mucus volume by fixing biopsied tissue sections taken from patients with UC in Carnoy's solution and compared it with endoscopic and pathological findings to determine whether there is a correlation between them. Observational study. A single-center, university hospital in Japan. Twenty-seven patients with UC (male/female, 16/11; mean age, 48.4 years; disease median duration, 9 years) were included in the study. The colonic mucosa of the most inflamed area and the surrounding less inflamed area were evaluated separately by local MES and endocytoscopic (EC) classification. Two biopsies were taken from each area; one was fixed with formalin for histopathological evaluation, and the other was fixed with Carnoy's solution for the quantitative evaluation of mucus via histochemical Periodic Acid Schiff and Alcian Blue staining. The relative mucus volume was significantly reduced in the local MES 1-3 groups, with worsening findings in EC-A/B/C and in groups with severe mucosal inflammation, crypt abscess, and severe reduction in goblet cells. The severity of inflammatory findings in UC by EC classification correlated with the relative mucus volume suggesting functional mucosal healing. We found a correlation between the colonic mucus volume and endoscopic and histopathological findings in patients with UC, and a stepwise correlation with disease severity, particularly in EC classification.

Rheumatoid Arthritis Symptoms Diagnosed by Rheumatic Immune-related Adverse Events Caused by Nivolumab in a Patient with Esophageal Cancer.

This report described the case of a 70-year-old man who developed polyarthralgia after nivolumab treatment for recurrent esophageal cancer. Arthritis developed after initiating nivolumab therapy, and the patient tested positive for rheumatoid factor and anti-citrullinated peptide antibodies. The hand and elbow joints were already deformed, suggesting that he had had rheumatoid arthritis for several years and that the symptoms had only become apparent after nivolumab administration. This patient had rheumatoid arthritis, which was diagnosed as a nivolumab-induced rheumatic immune-related adverse event (rh-irAEs). Arthralgia during nivolumab administration can occur in rh-irAE cases. Patients should be assessed for autoimmune diseases before initiating immune checkpoint inhibitors.

Current Status and Future Perspectives of Artificial Intelligence in Colonoscopy.

The early endoscopic identification, resection, and treatment of precancerous adenoma and early-stage cancer has been shown to reduce not only the prevalence of colorectal cancer but also its mortality rate. Recent advances in endoscopic devices and imaging technology have dramatically improved our ability to detect colorectal lesions and predict their pathological diagnosis. In addition to this, rapid advances in artificial intelligence (AI) technology mean that AI-related research and development is now progressing in the diagnostic imaging field, particularly colonoscopy, and AIs (i.e., devices that mimic cognitive abilities, such as learning and problem-solving) already approved as medical devices are now being introduced into everyday clinical practice. Today, there is an increasing expectation that sophisticated AIs will be able to provide high-level diagnostic performance irrespective of the level of skill of the endoscopist. In this paper, we review colonoscopy-related AI research and the AIs that have already been approved and discuss the future prospects of this technology.

New Closure Method Using Loop and Open-Close Clips after Endoscopic Submucosal Dissection of Stomach and Colon Lesions.

Endoscopic submucosal dissection (ESD) and en bloc resection of stomach and colon tumors have become common. However, mucosal defects resulting from ESD may cause delayed bleeding and perforation. To prevent adverse events, we developed a new clip closure technique, namely, the loop and open-close clip closure method (LOCCM), and aimed to examine its efficacy after ESD for stomach and colon tumors. The LOCCM uses loop and open-close clips. Here, the open-close clip was used to grasp the loop to bring it to the edge of the post-ESD mucosal defect. Another clip with a loop was then inserted into the opposite edge and clipped to the contralateral mucosa to pull both edges together. Once apposed, additional clips facilitated complete closure. The LOCCM was performed in 19 patients after ESD at Tottori University between October 2020 and March 2021. The outcomes retrospectively analyzed were the LOCCM success and adverse event rates. The complete closure rate using LOCCM was 89.5% and none of the patients had post-ESD bleeding or perforation. The results show that LOCCM is an effective and safe closure technique for mucosal defects after stomach and colon ESD to prevent bleeding and perforation.

Neutrophil-to-Lymphocyte Ratio Is a Useful Marker for Predicting Histological Types of Early Gastric Cancer.

BACKGROUND: The indications for endoscopic submucosal dissection (ESD) for gastric cancer are based on preoperative histological assessment; however, examination of tissue biopsy is not always reliable as only a limited portion of the lesion can be obtained. The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are markers of inflammatory response and are potentially associated with the grade of malignancy in gastric cancer. We aimed to investigate the association between NLR and PLR and the histology of gastric cancer. METHODS: This study included 218 patients who underwent ESD for gastric cancer. The relationship between NLR/PLR and histological diagnosis was investigated. RESULTS: Patients with adenocarcinomas showed significantly higher NLR and PLR than those with adenomas (p < 0.001 and p < 0.05, respectively). Further, patients with undifferentiated adenocarcinoma showed a significantly higher NLR (p < 0.05) than those with differentiated adenocarcinoma. CONCLUSION: This study suggests that NLR could be a useful marker for assessing early gastric cancer.

Salvage Photodynamic Therapy Using Talaporfin Sodium for Local Failure of Esophageal Squamous Cell Carcinoma.

BACKGROUND: Talaporfin sodium photodynamic therapy (TS-PDT) for local failure after chemoradiotherapy (CRT) in patients with esophageal squamous cell carcinoma has recently been reported to be highly effective and less invasive, compared to other treatment modalities. TS-PDT was recently introduced at the Tottori University Hospital, Japan. The aim of this study is to clarify the efficacy and safety of PDT in our hospital. METHODS: This was a single-center observational study. We examined eight cases of TS-PDT performed between January 2016 and December 2019. The main endpoints were local complete remission (L-CR) rate and the adverse events. In addition, age, gender, histology, tumor location, TNM stage, tumor depth, irradiation dose, and overall survival (OS) were examined. RESULTS: The patients included 7 men and a woman, with an average age of 72.1 years (range 63-82 years). The baseline clinical stages before CRT or radiotherapy were stage I in 1, stage II in 3, stage III in 3, and stage IVA in 1 patient. The T stage on endoscopic assessment before TS-PDT was T1 in 6 patients and T2 in 2 patients. Treatment outcomes and adverse events were evaluated. There were no treatment-related deaths, and no significant adverse events occurred intraoperatively or postoperatively. The L-CR rate was 7/8 (87.5%); T1 cases had 100% (6/6) L-CR, while T2 cases had 50% (1/2). The 2-year OS rates were 87%. CONCLUSION: TS-PDT was observed to be safe and effective in the first eight cases of its application following its introduction in our hospital.

Obstructive cholangitis by mucus from an intraductal papillary mucinous neoplasm with pancreatobiliary fistula treated by endoscopic septotomy and direct peroral cholangioscopy: a case report.

Intraductal papillary mucinous neoplasms (IPMNs) occasionally form a fistula to adjacent organs, resulting in obstructive jaundice and cholangitis due to mucus obstruction. Although some procedures such as endoscopic nasobiliary drainage are attempted, they often do not work adequately because of high mucus viscosity. Herein, we report the case of an 87-year-old man with obstructive cholangitis treated by endoscopic septotomy and mucus suction with direct peroral cholangioscopy using conventional endoscopy. The patient incidentally showed a branched-type IPMN in the pancreatic head on computed tomography (CT) approximately 10-years ago. Although the patient's tumor had grown slowly and he occasionally developed cholangitis, he did not want surgery. He was admitted to our hospital because of cholangitis by mucus obstruction with a PB fistula. Endoscopic retrograde cholangiopancreatography (ERCP) and septotomy were performed. Septotomy made the duodenal papilla a large orifice, thereby facilitating spontaneous drainage of mucus. In addition, conventional endoscopy with a large working channel enabled direct access into the orifice and smooth mucus suction, thereby alleviating his cholangitis. In conclusion, septotomy and direct peroral cholangioscopy using conventional endoscopy could be useful to control biliary tract infection and obstructive jaundice due to mucus obstruction from an IPMNs with PB fistula.