Usefulness of linked color imaging for the detection of obscure early gastric cancer: Multivariate analysis of 508 lesions.

OBJECTIVES: Early gastric cancers (EGCs) of the elevated type or with submucosal invasion are easily found by routine endoscopy. However, most early cancers are challenging to detect because of subtle morphological or color differences from surrounding atrophic mucosa and intestinal metaplasia. Linked color imaging (LCI) enhances mucosal color difference, making it easier to detect EGCs. The aim of this study is to clarify the advantages and possible disadvantages of LCI for screening for obscure EGC. METHODS: A total of 665 malignant gastric lesions resected using endoscopic submucosal dissection between January 2015 and April 2018 were retrospectively reviewed. Obviously detectable lesions were not included in the main analysis when determining the target lesion. White light imaging (WLI)/LCI images of 508 endoscopically obscure malignant lesions were included in the final analysis and evaluated by three non-expert and three expert endoscopists using visibility scores for detection and extent. RESULTS: The detection visibility scores using LCI were significantly higher than those using WLI regardless of lesion characteristics including location, size, histological type, depth of invasion, and Helicobacter pylori status. The detection score improved in 46.4% cases and deteriorated in 4.9% when the modality changed from WLI to LCI. A mixed-effects multivariate logistic regression analysis showed that use of LCI (odds ratio [OR] 2.57), elevated type (OR 1.92), invasion to submucosa (OR 2.18) were significantly associated with improved visibility of EGC. CONCLUSIONS: Linked color imaging significantly improves visibility of EGC regardless of differences in lesion morphology, histology, location, depth of invasion, and H. pylori status compared to conventional WLI.

Esophageal endoscopic submucosal dissection using sodium hyaluronate is safe and effective.

BACKGROUND/AIMS: A submucosal cushion of sodium hyaluronate facilitates gastric and colorectal endoscopic submucosal dissection (ESD). However, few studies have evaluated the utility of sodium hyaluronate for ESD of esophageal lesions. The aim of this study is to evaluate the utility and safety of sodium hyaluronate for ESD of superficial esophageal squamous cell neoplasms (ESCN). MATERIAL AND METHODS: We retrospectively reviewed 111 ESCN in 86 patients treated by ESD between September 2007 and April 2013. There were four double cancers, with 107 ESD procedures analyzed. RESULTS: The en bloc resection rate was 99% (106/107). The R0 resection rate was 93% (99/107). Of 106 specimens resected en bloc, four specimens had a positive horizontal margin, two specimens had non-assessable horizontal margins and one specimen had non-assessable horizontal and vertical margins. One patient with a non-assessable horizontal margin developed local recurrence seven months later, treated by repeat ESD. Delayed bleeding occurred in two procedures (2%), and intra-procedural perforation occurred in four (4%). None required operative repair. Endoscopy trainees performed 33 of 107 (31%) ESD procedures. Post-ESD stenosis requiring dilation occurred following five procedures (5%). CONCLUSIONS: Sodium hyaluronate for ESD of ESCN achieves a high R0 resection rate with a low rate of adverse events.

Efficacy and safety of endoscopic submucosal dissection for superficial colorectal tumors more than 50 mm in diameter.

BACKGROUND AND AIMS: The feasibility of endoscopic submucosal dissection (ESD) for large superficial colorectal tumors is undefined. The aim of this study was to assess the outcomes for patients undergoing ESD of superficial colorectal tumors larger than 50 mm. METHODS: A total of 472 patients who underwent ESD for superficial colorectal tumors from 2010 to 2014 were enrolled. We retrospectively reviewed their records. RESULTS: We compared patients with 20-mm to 50-mm lesions and those with lesions >50 mm regarding demographics, the ESD procedure, and histopathology. Among patients with lesions >50 mm, laterally spreading tumors nongranular and protruded types were uncommon. Histopathologically, deeply invasive (≥1000 µm) submucosal carcinomas were more frequent in lesions >50 mm (14% [10/70] vs 5% [20/402], P < .01). Technically, en bloc resection was successfully accomplished in 99% of patients (69/70). Although the total dissection time for lesions >50 mm was significantly longer than for lesions 20 mm to 50 mm (mean ± SD, 157 ± 114 minutes vs 68 ± 50 min; P < .01), dissection speed for lesions >50 mm was significantly faster than for lesions 20 mm to 50 mm (P < .01). There were no significant differences in en bloc R0 resection rate comparing both groups (>50 mm, 83% vs 20 mm to 50 mm, 87%; P = .31). No perforations or postoperative bleeding occurred in patients with lesions >50 mm. Post-ESD colorectal strictures requiring intervention did not develop in any patient. CONCLUSIONS: ESD for superficial colorectal tumors >50 mm is feasible. ESD of these lesions had a high R0 resection rate and a low adverse event rate. En bloc resection by ESD provides adequate pathological specimens and may limit the need for surgical intervention.

Pancreatitis and cholangitis caused by metallic wire in the duodenal submucosa and muscularis near the papilla: removal by endoscopic submucosal dissection using the pocket-creation method.

Video 1A metalic wire removed by endoscopic submucosal dissection using the pocket-creation method.

Impact of linked color imaging and blue laser imaging on the diagnosis of esophageal squamous cell carcinoma in iodine unstained areas.

The pink color sign in iodine unstained areas is useful to differentiate esophageal squamous cell carcinoma (ESCC) from other lesions. However, some ESCCs have obscure color findings which affect the ability of endoscopists to differentiate these lesions and determine the resection line. Using white light imaging (WLI), linked color imaging (LCI) and blue laser imaging (BLI), 40 early ESCCs were retrospectively evaluated using images before and after iodine staining. Visibility scores for ESCC by expert and non-expert endoscopists were compared using these three modalities and color differences measured for malignant lesions and surrounding mucosa. BLI had the highest score and color difference without iodine staining. Each determination with iodine was much higher than without iodine regardless of the modality. With iodine, ESCC mainly appeared pink, purple and green using WLI, LCI and BLI, respectively and visibility scores determined by non-experts and experts were significantly higher for LCI (both p < 0.001) and BLI (p = 0.018 and p < 0.001) than for WLI. The score with LCI was significantly higher than with BLI among non-experts (p = 0.035). With iodine, the color difference using LCI was twice that with WLI and one with BLI was significantly larger than with WLI (p < 0.001). These greater tendencies were found regardless of location, depth of cancer or intensity of pink color using WLI. In conclusion, areas of ESCC unstained by iodine were easily recognized using LCI and BLI. Visibility of these lesions is excellent even by non-expert endoscopists, suggesting that this method is useful to diagnose ESCC and determine the resection line.

Improved detection of early gastric cancer with linked color imaging using an ultrathin endoscope: a video-based analysis.

Background and study aims Ultrathin endoscopy causes a minimal gag reflex and has minimal effects on cardiopulmonary function. Linked color imaging (LCI) is useful for detection of malignancies in the digestive tract. The aim of this study was to clarify whether LCI with ultrathin endoscopy facilitates detection of early gastric cancer (EGC) despite its lower resolution compared with high-resolution white light imaging (WLI) with standard endoscopy. Patients and methods This was a retrospective analysis with prospectively collected video, including consecutive 166 cases of EGC or gastric atrophy alone. Ninety seconds of screening video was collected using standard and ultrathin endoscopes with both WLI and LCI for each case. Three expert endoscopists assessed each video and the sensitivity of detecting EGC calculated. Color difference calculations were performed. Results Sensitivities using ultrathin WLI, ultrathin LCI, standard WLI, and standard LCI for the identification of cancer were 66.0 %, 80.3 %, 69.9 %, and 84.0 %, respectively. The color difference between malignant lesions and surrounding mucosa with ultrathin LCI and standard LCI were significantly higher than using ultrathin WLI or standard WLI, supported subjectively by the visibility score. Ultrathin LCI color difference and visibility score were significantly higher than standard WLI. Conclusions LCI with a low-resolution ultrathin endoscope is superior to WLI with a high-resolution standard endoscope for gastric cancer screening. This suggests that the high color contrast between EGC and the surrounding mucosa is more important than high-resolution images.

Non-exposed endoscopic wall-inversion surgery for pediatric gastrointestinal stromal tumor: A case report.

Gastrointestinal stromal tumors (GIST) in patients under 18 years of age are classified as pediatric GIST. Pediatric GIST are extremely rare, and there are no reports of laparoscopic-endoscopic cooperative surgery for these lesions. We report the use of non-exposed endoscopic wall-inversion surgery as a laparoscopic-endoscopic cooperative surgery-related procedure for the treatment of a pediatric GIST. The case involved a 17-year-old male patient who presented with anemia and was found to have a bleeding gastric tumor. The tumor was resected transorally using the non-exposed endoscopic wall-inversion surgery technique. No gene mutation of c-Kit or Platelet-Derived Growth Factor Receptor α (PDGFRα) was found, and the final pathological diagnosis was epithelial-type GIST due to a succinate dehydrogenase abnormality. Follow-up included a CT scan every 4 months. No recurrence has occurred to date.

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 can enhance recognition of early gastric cancer by high color contrast to surrounding gastric intestinal metaplasia.

BACKGROUND: Linked color imaging (LCI) increases the visibility of early gastric cancers, which may be associated with characteristic findings including background purple mucosae. These lesions are found in areas of chronic gastritis and surrounding mucosa. The aim of this study is to objectively characterize these lesions by color differences and color component values using LCI. METHODS: Fifty-two patients with early gastric cancer were enrolled. Color differences were calculated prospectively in malignant lesions and adjacent mucosa and compared with histological findings in resected specimens. Color component values of L*, a*, and b* were compared between purple and non-purple mucosae in areas of chronic gastritis. Based on histological findings, the accuracy of identifying gastric intestinal metaplasia was calculated. RESULTS: Cancers and surrounding mucosa in 74% of lesions had similar colors using white light imaging (WLI), whereas purple mucosa surrounded part or all of cancers appearing orange-red, orange or orange-white using LCI. Greater color differences were seen using LCI compared to WLI, including flat-type cancers, leading to higher contrast. The surrounding purple mucosa corresponded histologically to intestinal metaplasia, facilitating the identification of malignant lesions. Forty lesions (83%) with purple mucosa and eight lesions (17%) with non-purple mucosa in areas of chronic gastritis were diagnosed as intestinal metaplasia by biopsy (83% accuracy). Color component values of purple mucosa differ significantly from those of non-purple mucosae. CONCLUSIONS: LCI images have higher color contrast between early gastric cancers and surrounding mucosa compared to WLI. A characteristic purple color around gastric cancers using LCI represents intestinal metaplasia.

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.

Laser Imaging Facilitates Early Detection of Synchronous Adenocarcinomas in Patients with Barrett's Esophagus.

Barrett's adenocarcinoma may occur in multiple sites, and recurrence and metachronous lesions are the major problems with endoscopic resection. Therefore, early detection of such lesions is ideal to achieve complete resection and obtain improved survival rates with minimally invasive treatment. Laser imaging systems allow multiple modalities of endoscopic imaging by using white light laser, flexible spectral imaging color enhancement (FICE), blue laser imaging (BLI), and linked color imaging even at a distant view. However, the usefulness of these modalities has not been sufficiently reported regarding Barrett's adenocarcinoma. Here, we report on a patient with three synchronous lesions followed by one metachronous lesion in a long segment with changes of Barrett's esophagus, all diagnosed with this new laser endoscopic imaging system and enhanced by using FICE and/or BLI with high contrast compared with the surrounding mucosa. Laser endoscopic imaging may facilitate the detection of malignancies in patients with early Barrett's adenocarcinoma.