The Association between the Growth Pattern and Malignancy in the Formation of Ulceration in Gastric Gastrointestinal Stromal Tumor.

Objective In general, surface ulceration in gastric gastrointestinal stromal tumor (GIST) is considered a malignant feature; however, the mechanism underlying its formation has not been evaluated in detail. In this study, we analyzed the factors involved in ulceration using resected specimens of gastric GIST. Methods A total of 48 samples were retrospectively analyzed. We examined the association of surface ulceration of gastric GIST with the MIB-1 labeling index, mitotic number, tumor size, endoscopic ultrasound (EUS) findings and growth pattern on computed tomography (CT). Results The proportion of men was significantly higher in the ulceration group than in the non-ulceration group (p=0.04146), whereas age was not significantly different between the groups. Tumor was significantly larger in the ulceration group than in the non-ulceration group (p=0.0048). There was no correlation between tumor size and ulcer number. The MIB-1 index was not related to ulceration, nor were EUS findings. The number of mitotic cells tended to be higher in the ulceration group than in the non-ulceration group (p=0.05988). Intraluminal growth pattern was strongly associated with ulceration (p=0.00019). After a multivariate analysis, the growth pattern was the only factor associated with ulceration of gastric GIST. Conclusion Although formation of surface ulceration in gastric GIST was partially associated with the degree of malignancy, the growth pattern was the most important factor associated with ulceration in gastric GIST.

Novel image enhancement technology that helps find bleeding points during endoscopic submucosal dissection of gastric neoplasms.

BACKGROUND AND AIM: The management of bleeding during endoscopic submucosal dissection (ESD) is critical and related to the procedure time. We collaborated on a new image enhancement algorithm with parameter optimization for clinical use being developed by FUJIFILM Co. and processed white light image data offline to evaluate the effectiveness of this technology. This study aims to evaluate the clinical usefulness of this technology. METHODS: Eighteen video scenes of bleeding points from five gastric ESDs were selected and processed by the new image enhancement algorithm. The time until a bleeding point was found, visibility of a bleeding point, and color abnormality of the submucosal layer were evaluated by ESD experts, ESD trainees, and endoscopy trainees. The color differences between the bleeding point and the surroundings in CIE-L*a*b* color space were calculated in the original and enhanced images. RESULTS: The time until a bleeding point was found in the enhanced videos was significantly shorter than that in the original videos (11.10 s vs 13.85 s) (P = 0.017). On a 5-point (-2 to +2) Likert scale of visibility, the enhanced image was slightly superior to the original (+0.45), and the appearance of the submucosa was comparable between images (+0.14). The color difference among the bleeding areas on the enhanced images was significantly larger than that on the original images (10.93 vs 8.36). CONCLUSION: This novel image enhancement algorithm emphasizes the color difference between a bleeding point and the surrounding area, which would help find bleeding points faster during ESD for the less experienced endoscopists.

Complete omission of second-look endoscopy after gastric endoscopic submucosal dissection in real-world practice.

Gastric endoscopic submucosal dissection (ESD) is increasingly performed in patients receiving antithrombotic therapy. Second-look endoscopy (SLE) has been performed empirically in several clinical settings. We investigated whether SLE omission was associated with an increased risk of postESD bleeding in all patients, including those administered antithrombotic agents. Between July 2016 and June 2018, 229 patients were treated with a clinical pathway for gastric ESD that involved SLE on the day after ESD (SLE group). Between September 2018 and May 2020, 215 patients were treated using a clinical pathway that did not include SLE (nonSLE group). We retrospectively compared the incidence of postESD bleeding among the propensity score-matched cohorts and determined the risk factors for postESD bleeding using multivariate analysis. The propensity score-matched cohorts showed no significant differences in the incidence of postESD bleeding between the SLE (3.2%) and nonSLE (5.1%) groups. Multivariate analysis revealed that the presence of lesions in the lower gastric body (adjusted odds ratio [OR] 2.17, 95% confidence interval [CI] 1.06-4.35, P.03) was a significant risk factor for postESD bleeding during admission, whereas resected specimen size ≥ 40 mm (adjusted OR 3.21, 95% CI 1.19-8.19, P.02) and antiplatelet therapy (adjusted OR 4.16, 95% CI 1.47-11.80, P.007) were significant risk factors after discharge. Complete omission of SLE after gastric ESD does not increase postESD bleeding in clinical practice.

Usefulness of Full-spectrum Endoscopy for the Upper Gastrointestinal Tract.

GOALS: We determined whether full-spectrum endoscopy (FUSE) improved the visualization rates of blind spots in a single-center case control study. BACKGROUND: FUSE provides a 210-degree angle of view with a left side-viewing camera in addition to a forward-viewing camera. FUSE can improve the detectability of blind spots in conventional forward-viewing esophagogastroduodenoscopy (EGD), such as the major duodenal papilla (MDP) and the anal side of the pyloric ring. STUDY: Between April 2016 and May 2017, successful visualization rates of the whole MDP and anal side of the pyloric ring were compared between 103 participants who underwent FUSE and 1045 participants who underwent EGD. Pain and discomfort at insertion and during and after the examination were assessed using a visual analog scale in 38 participants who underwent FUSE with a previous examination history of EGD. RESULTS: The successful visualization rates of MDP and the anal side of the pyloric ring in the FUSE group were significantly higher than those in the conventional EGD group; 83.4% versus 35.1% for MDP (P<0.001) and 86.4% versus 7.1% for the anal side of the pyloric ring (P<0.001), respectively. The visual analog scale were not significantly different between FUSE and previous EGD in a portion of the FUSE group. In addition, the detection rate of the periampullary diverticula was also significantly higher in the FUSE group than that in the conventional EGD group (8.7% vs. 1.6%, P<0.001). CONCLUSIONS: This study provides evidence supporting that FUSE is superior to EGD for precise visualization of blind spots in the duodenum.

Development of a Comorbidity Index to Identify Patients With Small Bowel Bleeding at Risk for Rebleeding and Small Bowel Vascular Diseases.

BACKGROUND & AIMS: We aimed to establish a comorbidity index for small bowel vascular diseases (SBVD) associated with small bowel bleeding (SBB) and recurrent bleeding. METHODS: We performed a retrospective analysis of 404 patients diagnosed with SBB via double-balloon enteroscopy, at 2 hospitals in Japan from June 2003 through July 2016. We collected data on comorbidities, computed Charlson Comorbidity Index and anticoagulation and risk factors in atrial fibrillation (ATRIA) scores, and analyzed associations with SBVD, rebleeding, and overall survival associated with bleeding and/or comorbidities. We used these data to develop a comorbidity index to identify patients at risk for SBVD, rebleeding, and reduced survival time. We validated our findings in a separate, prospective cohort of 88 patients with SBB. RESULTS: We developed a weighted index (the Ohmiya index) that identified patients who developed SBVD with an area under the receiver operating characteristic (AUROC) curve of 0.7758; this value was higher than that of the Charlson index score (0.6828; P < .0001) or ATRIA score (0.6728; P < .0001) alone. Among the 51 patients taking oral anticoagulants, there was no significant difference in AUROCs for the Ohmiya score (0.5254) vs the outcomes registry for better informed treatment score (0.5857; P = .4300). In the retrospective cohort, the Ohmiya index identified patients with SBVD with 68% sensitivity (93/137), 84% specificity (223/267), and 78% accuracy (316/404); in the validation cohort, these values were 63% (22/35), 85% (45/53), and 76% (67/88), respectively. Onset age <50 years and index score <2 identified patients with Meckel's diverticulum and Crohn's disease with 53% accuracy. Onset age ≥50 years and index score <2 identified patients with inflammatory diseases, drug-induced injuries, or tumors with 72% accuracy. An index score ≥2 identified patients with SBVD with 68% accuracy, regardless of age. Among patients with Ohmiya index scores ≥2, 33% had rebleeding; among patients with scores <2, 15% had rebleeding (hazard ratio for score ≥2, 1.729; 95% CI, 1.038-2.882; P = .0355). CONCLUSION: We developed an index, based on comorbidities and age of onset of SBB, that identified patients at risk for rebleeding and vascular disease (for example, enteroscopic hemostasis for SBVD, medication for inflammatory diseases, surgery with enteroscopic tattooing for tumors and diverticula). UMIN: 000025693.

Molecular subtyping of gastric cancer combining genetic and epigenetic anomalies provides distinct clinicopathological features and prognostic impacts.

Both genetic and epigenetic abnormalities play important roles in gastric cancer (GC) development. We investigated whether the molecular subtypes of gastric cancer by combining genetic and epigenetic anomalies define its clinicopathological features and prognosis. The CpG island methylator phenotype (CIMP), MLH1 methylation, TP53, and KRAS mutation statuses were characterized in 214 GCs in relation to their clinicopathological features and prognosis. The molecular subtypes based on CIMP and TP53 hot spot mutation status (R175, G245, R248, R273, and R282) best predicted prognosis of GC. These subtypes contained 120 CIMP-positive (CIMP+) TP53 hot spot mutation-negative (TP53 hot spot-) cases, 81 CIMP-negative (CIMP-) TP53 hot spot- cases, 8 CIMP+TP53 hot spot mutation-positive (TP53 hot spot+) cases, and 5 CIMP- TP53 hot spot+ cases. The CIMP-TP53 hot spot+ group presented the worst overall survival (OS) and progression-free survival (PFS), followed by the CIMP+TP53 hot spot+, CIMP-TP53 hot spot- and CIMP+TP53 hot spot- groups (both P < 0.0001). These subtypes also correlated well with several aggressive clinicopathological features in that order. The molecular subtypes were independent factors for predicting overall survival (hazard ratio = 1.66, 95% CI = 1.07-2.57, P = 0.006). The molecular subtypes combining the CIMP and TP53 hot spot mutation status provide distinct clinicopathological features and prognostic impacts in GC.

Erratum to 'Jejunal GI tumor using probe-based confocal laser endomicroscopy': [VideoGIE 2018;3:220-2].

[This corrects the article DOI: 10.1016/j.vgie.2018.04.010.].