Advanced Treatment and Imaging in Colonoscopy: The Pocket-Creation Method for Complete Resection and Linked Color Imaging for Better Detection of Early Neoplastic Lesions by Colonoscopy

Early detection and resection of neoplastic lesions are key objectives to diminish colorectal cancer mortality. Resection of superficial colorectal neoplasms, cold snare polypectomy, endoscopic mucosal resection, and endoscopic submucosal dissection have all been developed and used worldwide. The pocket-creation method facilitates the resection of tumors in difficult and routine locations. Early detection is the most important first step to maximize the benefits of recent advancements in endoscopic techniques. However, the detection of small, flat-shaped, or faded color lesions remains difficult. Linked color imaging, a novel multi-light technology, facilitates the recognition of minor differences in tissue by enhancing the color contrast between early colorectal neoplasms and surrounding normal mucosa in a bright field of view. The most striking feature of linked color imaging is its ability to display the color of early neoplastic lesions as distinct from inflammatory changes, both of which have similar “redness” when viewed using white light imaging. To increase the detection rate of neoplasms, linked color imaging should be used from the outset for endoscopic observation. Early detection of superficial colorectal tumors can result in decreased mortality from colorectal cancer and maintain a good quality of life for patients

Blue Laser Imaging with a Small-Caliber Endoscope Facilitates Detection of Early Gastric Cancer

Conventional endoscopy often misses early gastric cancers with minimal red discoloration because they cannot be distinguished from inflamed mucosa. We treated a patient with a small early gastric cancer that was difficult to diagnose using conventional endoscopy. Conventional endoscopy using a small-caliber endoscope showed only subtle red discoloration of the gastric mucosa. However, blue laser imaging showed a clearly discolored area measuring 10 mm in diameter around the red lesion, which was distinct from the surrounding inflamed mucosa. Irregular vessels on the tumor surface (suspicious for early gastric cancer) were observed even with small-caliber endoscopy. Biopsy revealed a well-moderately differentiated tubular adenocarcinoma, and endoscopic submucosal dissection was performed. Histopathological examination of the specimen confirmed well-moderately differentiated adenocarcinoma localized to the mucosa with slight depression compared to the surrounding mucosa, consistent with the endoscopic findings. This small early gastric cancer became clearly visible with blue laser imaging using small-caliber endoscopy

Linked Color Imaging and Blue Laser Imaging for Upper Gastrointestinal Screening

White light imaging (WLI) may not reveal early upper gastrointestinal cancers. Linked color imaging (LCI) produces bright images in the distant view and is performed for the same screening indications as WLI. LCI and blue laser imaging (BLI) provide excellent visibility of gastric cancers in high color contrast with respect to the surrounding tissue. The characteristic purple and green color of metaplasias on LCI and BLI, respectively, serve to increase the contrast while visualizing gastric cancers regardless of a history of Helicobacter pylori eradication. LCI facilitates color-based recognition of early gastric cancers of all morphological types, including flat lesions or those in an H. pylori-negative normal background mucosa as well as the diagnosis of inflamed mucosae including erosions. LCI reveals changes in mucosal color before the appearance of morphological changes in various gastric lesions. BLI is superior to LCI in the detection of early esophageal cancers and abnormal findings of microstructure and microvasculature in close-up views of upper gastrointestinal cancers. Excellent images can also be obtained with transnasal endoscopy. Using a combination of these modalities allows one to obtain images useful for establishing a diagnosis. It is important to observe esophageal cancers (brown) using BLI and gastric cancers (orange) surrounded by intestinal metaplasia (purple) and duodenal cancers (orange) by LCI

The pocket-creation method of endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is rapidly becoming the standard treatment for superficial gastrointestinal tumors because ESD can achieve complete local resection facilitating thorough pathological examination of the resected specimen. The pocket-creation method (PCM) has been established to perform safe and reliable ESD obtaining a high-quality pathological specimen. A minimal mucosal incision using PCM minimizes leakage of submucosally injected solution, which results in prolonged mucosal elevation. A limited-space submucosal pocket created using PCM makes the endoscope tip stable. A conical cap, small-caliber-tip transparent (ST) hood is used when performing PCM. The submucosa can be cut along the ideal dissection line just above the muscularis with minimal thermal damage because the tip of the ST hood produces both traction and countertraction to stretch the submucosal tissue in the pocket. PCM is recommended as the standard strategy not only for colorectal ESD but also for upper-gastrointestinal ESD. It is expected that the use of traction techniques will make PCM easier to perform

An Ultrathin Endoscope with a 2.4-mm Working Channel Shortens the Esophagogastroduodenoscopy Time by Shortening the Suction Time

Background/Aims: Poor suction ability through a narrow working channel prolongs esophagogastroduodenoscopy (EGD). The aim of this study was to evaluate suction with a new ultrathin endoscope (EG-580NW2; Fujifilm Corp.) having a 2.4-mm working channel in clinical practice. Methods: To evaluate in vitro suction, 200 mL water was suctioned and the suction time was measured. The clinical data of 117 patients who underwent EGD were retrospectively reviewed on the basis of recorded video, and the suction time was measured by using a stopwatch. Results: In vitro, the suction time with the EG-580NW2 endoscope was significantly shorter than that with the use of an ultrathin endoscope with a 2.0-mm working channel (EG-580NW; mean ± standard deviation, 22.7±1.1 seconds vs. 34.7±2.2 seconds; p<0.001). We analyzed the total time and the suction time for routine EGD in 117 patients (50 in the EG-580NW2 group and 67 in the EG-580NW group). In the EG-580NW2 group, the total time for EGD was significantly shorter than that in the EG-580NW group (275.3±42.0 seconds vs. 300.6±46.5 seconds, p=0.003). In the EG-580NW2 group, the suction time was significantly shorter than that in the EG-580NW group (19.2±7.6 seconds vs. 38.0±15.9 seconds, p<0.001). Conclusions: An ultrathin endoscope with a 2.4-mm working channel considerably shortens the routine EGD time by shortening the suction time, in comparison with an endoscope with a 2.0-mm working channel

Vonoprazan treatment improves gastrointestinal symptoms in patients with gastroesophageal reflux disease

The effects of vonoprazan, a new potassium-competitive acid blocker, on gastroesophageal reflux disease (GERD) symptom are not fully elucidated. The aim of this study is to determine the effect of vonoprazan on GERD and associated gastrointestinal symptoms. We retrospectively reviewed 88 Helicobacter pylori negative patients with GERD treated with vonoprazan 10 mg daily. Symptoms were evaluated using the Izumo scale, which reflects quality of life related to various abdominal symptoms. The rates of improvement and resolution of GERD symptoms were 86% (76/88) and 57% (50/88), respectively. Improvement and resolution in patients with erosive esophagitis was higher than in those with non-erosive reflux disease (91% vs 83%, p = 0.260 and 71% vs 47%, p = 0.025, respectively). We attempted to identify factors which predict the effects of vonoprazan. Multivariate analysis identified advanced age (≥60-year-old) (odds ratio [OR] 7.281, 95% confidence interval [CI] 2.056–25.776, p = 0.002), obesity (BMI ≥ 24) (OR 3.342, 95%CI 1.124–9.940, p = 0.030) and erosive esophagitis (OR 4.368, 95%CI 1.281–14.895, p = 0.018) as positive predictors of resolution of GERD symptoms. Alcohol use (OR 0.131, 95%CI 0.027–0.632, p = 0.011) and history of H. pylori eradication (OR 0.171, 95%CI 0.041–0.718, p = 0.015) were identified as negative predictors. Vonoprazan also improved epigastric pain (73%), postprandial distress (60%), constipation (58%) and diarrhea (52%) in patients with GERD. In conclusion, vonoprazan 10 mg daily is effective in improving GERD symptoms. Advanced age, obesity, erosive esophagitis, alcohol use and history of H. pylori eradication influence the resolution of GERD symptoms. Treatment with vonoprazan favorably affects gastrointestinal symptoms in patients with GERD

Pre-treatment with proton pump inhibitors decreases the success of primary Helicobacter pylori eradication using a vonoprazan-based regimen

Vonoprazan-based regimens have improved the rate of successful Helicobacter pylori (H. pylori) eradication, but it has not reached 100%. The aim of this study is to clarify significant predictors of successful H. pylori eradication using a vonoprazan-based regimen. In this retrospective cohort study, 174 patients who underwent primary H. pylori eradication therapy were included. All patients underwent esophagogastroduodenoscopy before treatment. The vonoprazan-based regimen includes amoxicillin 750 mg, clarithromycin 200 mg and vonoprazan 20 mg twice daily for one week. Pre-treatment with a proton pump inhibitor (PPI) was defined as continued PPI use for more than four weeks prior to eradication therapy. The rates of successful eradication were 83% (145/174) in intention-to-treat analysis and 85% (145/171) in per-protocol analysis. Predictors of successful eradication among 171 patients were evaluated in per-protocol analysis. In univariate analysis, male gender was a significant positive predictor of successful eradication (odds ratio [OR] 3.813, 95% confidence interval [CI] 1.363–10.663, p = 0.010) and pre-treatment with PPIs was a negative predictor (OR 0.193, 95%CI 0.076–0.485, p < 0.001). In multivariate analysis, male gender remained a positive predictor (OR 3.826, 95%CI 1.317–11.116, p = 0.013), and pre-treatment with PPIs (OR 0.232, 95%CI 0.087–0.615, p = 0.003) remained a negative predictor. In conclusion, pre-treatment with PPIs before eradication therapy decreases the rate of successful eradication. Therefore, it may be desirable to discontinue pre-treatment with PPIs prior to eradication therapy, because of the potential to improve the rate of successful eradication. Keywords: Helicobacter pylori, Potassium-competitive acid blocker, Outcome measure, Proton pump inhibitor