Real-time diagnostic accuracy of blue light imaging, linked color imaging and white-light endoscopy for colorectal polyp characterization

Background and study aims Fujifilm has developed a novel ELUXEO 7000 endoscope system that employs light-emitting diodes (LEDs) at four different wavelengths as light sources that enable blue light imaging (BLI), linked color imaging (LCI), and high-definition white-light endoscopy (HD-WLE). The aim of this study was to address the diagnostic accuracy of real-time polyp characterization using BLI, LCI and HD-WLE (ELUXEO 7000 endoscopy system). Patients methods This is a prespecified post-hoc analysis of a prospective study in which 22 experienced endoscopists (> 2,000 colonoscopies) from eight international centers participated. Using a combination of BLI, LCI, and HD-WLE, lesions were endoscopically characterized including a high- or low-confidence statement. Per protocol, digital images were created from all three imaging modalities. Histopathology was the reference standard. Endoscopists were familiar with polyp characterization, but did not take dedicated training for purposes of this study. Results Overall, 341 lesions were detected in 332 patients. Of the lesions, 269 histologically confirmed polyps with an optical diagnosis were included for analysis (165 adenomas, 27 sessile serrated lesions, and 77 hyperplastic polyps). Overall, polyp characterization was performed with high confidence in 82.9 %. The overall accuracy for polyp characterization was 75.1 % (95 % confidence interval [CI] 69.5–80.1 %), compared with an accuracy of 78.0 % (95 % CI 72.0–83.2 %) for high confidence assignments. The accuracy for endoscopic characterization for diminutive polyps was 74.7 % (95 %CI 68.4–80.3 %), compared with an accuracy of 78.2 % (95 % CI 71.4–84.0 %) for high-confidence assignments. Conclusions The diagnostic accuracy of BLI, LCI, and HD-WLE by experienced endoscopist for real-time polyp characterization seems limited (NCT03344289).

Diagnostic ability of linked color imaging in ultraslim endoscopy to identify neoplastic lesions in the upper gastrointestinal tract

Background and study aims Linked color imaging (LCI) is a new image-enhancing technique that facilitates the differentiation of slight differences in mucosal color tone. We performed an exploratory analysis to evaluate the diagnostic capability of LCI in ultraslim endoscopy, using data from patients examined in the LCI-Further Improving Neoplasm Detection in upper gastrointestinal (LCI-FIND) trial, a large-scale, multicenter, randomized controlled trial that demonstrated the capability of LCI for detecting neoplastic lesions in the upper gastrointestinal tract. Patients and methods Data from the LCI-FIND prospective trial were used. In the LCI-FIND trial, 1502 patients with a history of gastrointestinal cancer were randomly assigned to two groups based on examination methods: white light imaging (WLI) followed by LCI (WLI group) and LCI followed by WLI (LCI group). The present exploratory analysis investigated the outcomes of patients who underwent ultraslim and standard endoscopies. Results Ultraslim endoscopes were used in 223 patients and standard endoscopes in 1279 patients. The primary endpoint of the LCI-FIND trial was the percentage of patients diagnosed with a neoplastic lesion using WLI or LCI. The corresponding percentage tended to be higher with LCI than with WLI among patients who underwent ultraslim endoscopy and among those who underwent standard endoscopy; the crude risk ratio was 2.21 [95 % confidence interval (CI): 1.06–4.67], and the adjusted odds ratio was 2.46 (95 % CI: 1.07–5.63). Conclusions Our exploratory analysis of data from the LCI-FIND trial showed that LCI is useful in identifying neoplastic lesions, when used in ultraslim endoscopy.

Detection of Early Gastric Cancer after Helicobacter pylori Eradication

<b><i>Background:</i></b> Based on evidence that <i>Helicobacter pylori</i> eradication reduces the development of gastric cancer and other diseases such as peptic ulcer, eradication therapy has prevailed. However, gastric cancer can develop even after successful eradication. <b><i>Summary:</i></b> In this review article, we searched for studies that identified the characteristics of primary and metachronous gastric cancers after <i>H. pylori</i> eradication, the risk factors for the development of these cancers after successful <i>H. pylori</i> eradication, and whether image-enhanced endoscopy is useful for diagnosing gastric cancer after eradication. A gastritis-like appearance is seen as a characteristic endoscopic finding, which corresponds to an epithelium with low-grade atypia – also known as nonneoplastic epithelium – covering the surface of the cancerous glands. This finding may make endoscopic detection of early gastric cancer difficult after <i>H. pylori</i> eradication. Similar risk factors, such as the male sex, endoscopic atrophy, histologic intestinal metaplasia, and late eradication, have been reported as predictors for the development of both primary and metachronous gastric cancers. Image-enhanced endoscopy, such as linked color imaging, may be useful for the detection and risk stratification of gastric cancer after eradication. <b><i>Key Messages:</i></b> Based on these findings, we believe that effective surveillance of high-risk patients leads to early detection of gastric cancer in the era of <i>H. pylori</i> eradication.

Improved Visibility of Early Gastric Cancer after Successful Helicobacter pylori Eradication with Image-Enhanced Endoscopy: A Multi-Institutional Study Using Video Clips

The visibility and diagnostic accuracy of early gastric cancer (EGC) after Helicobacter pylori (HP) eradication have been reported to improve using image-enhanced endoscopy (IEE) compared with white light imaging (WLI). The present study clarified the appropriate IEE for the detection and diagnosis of EGC in clinical settings. This prospective and cross-sectional study evaluated the visibility of EGC and endoscopic findings of gastric mucosa after successful HP eradication (n = 31) using videos with WLI and IEE. Three endoscopists evaluated high-definition videos in a randomized order. The mean visibility scores (MVSs) on linked color imaging (LCI) for atrophic border, intestinal metaplasia, map-like redness, and EGC were the highest among each modality (3.87 ± 0.34, 3.82 ± 0.49, 3.87 ± 0.50, and 3.35 ± 0.92, respectively). The MVSs with blue laser imaging (BLI) were highest for magnifying view of the demarcation line (DL), microsurface pattern (MSP), and microvascular pattern (MVP) for EGC (3.77 ± 0.49, 3.94 ± 0.25, and 3.92 ± 0.34, respectively). LCI had the highest visibility among findings of gastric mucosa and EGC after HP eradication, and BLI had the highest visibility of MVP, MSP, and DL in magnifying observation. These results suggest that LCI observation in the entire stomach and further magnifying BLI are the best methods for detecting and diagnosing EGCs after HP eradication, respectively.