Obscure gastrointestinal bleeding (OGIB) is defined as gastrointestinal bleeding from a source that cannot be identified on upper or lower gastrointestinal endoscopy. OGIB is considered an important indication for capsule endoscopy (CE). CE is particularly useful for the detection of vascular and small ulcerative lesions, conditions frequently associated with OGIB, particularly in Western countries. On the other hand, balloon enteroscopy (BE) can facilitate the diagnosis of lesions presenting with minimal changes of the mucosal surface, such as submucosal tumors, and can be used not only for diagnosis, but also for treatment, including endoscopic hemostasis. In other words, the complementary use of both CE and BE enables OGIB to be more efficiently diagnosed and treated. However, rebleeding can occur even in patients with negative results of CE, and such patients require repeat CE or BE. It is essential to effectively use both CE and BE based on a thorough understanding of the strong points and weak points of these procedures. Further advances and developments in virtual endoscopy incorporating computed tomography and magnetic resonance imaging are expected in the future.
Capsule Endoscopy ; Diagnosis* ; Endoscopy ; Endoscopy, Gastrointestinal ; Hand ; Hemorrhage* ; Hemostasis, Endoscopic ; Humans ; Magnetic Resonance Imaging ; Ulcer

BACKGROUND/AIMS: The diagnostic algorithms used for selecting patients with obscure gastrointestinal bleeding (OGIB) for capsule endoscopy (CE) or balloon-assisted enteroscopy (BE) vary among facilities. We aimed to demonstrate the appropriate selection criteria of CE and single balloon-assisted enteroscopy (SBE) for patients with OGIB according to their conditions, by retrospectively comparing the diagnostic performances of CE and BE for detecting the source of the OGIB. METHODS: We investigated 194 patients who underwent CE and/or BE. The rate of positive findings, details of the findings, accidental symptoms, and hemostasis methods were examined and analyzed. RESULTS: CE and SBE were performed in 103 and 91 patients, respectively, and 26 patients underwent both examinations. The rate of positive findings was significantly higher with SBE (73.6%) than with CE (47.5%, p<0.01). The rate of positive findings was higher in overt bleeding cases than in occult bleeding cases for both BE and SBE. Among the overt bleeding cases, the rate was significantly higher in ongoing bleeding cases than in previous bleeding cases. CONCLUSIONS: Both CE and SBE are useful to diagnose OGIB. For overt bleeding cases and ongoing bleeding cases, SBE may be more appropriate than CE because endoscopic diagnosis and treatment can be completed simultaneously.
Capsule Endoscopy* ; Diagnosis ; Hemorrhage* ; Hemostasis ; Humans ; Patient Selection ; Retrospective Studies

Background/Aims: Helicobacter pylori infection-negative gastric cancer (HPNGC) has not been systematically investigated in consecutive patients. Hence, this study aimed to investigate the clinicopathological and endoscopic features of HPNGC. Methods: This single-center retrospective study selected participants from patients with gastric cancer who were treated at the Fukuoka University Chikushi Hospital between January 2013 and December 2021. Only patients diagnosed with HPNGC were enrolled, and their clinicopathological and endoscopic features were analyzed in detail. Results: The prevalence of HPNGC in the present study was 2.6% (54/2112). The types of HPNGC observed in each gastric region were as follows: advanced gastric cancer was observed in the cardia; gastric adenocarcinoma of fundic-gland differentiation, gastric adenocarcinoma of foveolar-type presenting with whitish elevation and raspberry-like foveolar-type gastric adenocarcinoma, gastric adenocarcinoma arising in polyposis, and gastric adenocarcinoma with autoimmune gastritis were observed in the fundic gland region ranging from the gastric fornix to the gastric body; signet-ring cell carcinoma was observed in the gastric-pyloric transition region ranging from the lower gastric body to the gastric angle; and well-differentiated tubular adenocarcinoma with low-grade atypia was observed in the antrum. Conclusions This study revealed that tumors from each gastric region exhibited distinct macroscopic and histological types in HPNGC.

Purpose: Promoter DNA methylation of various genes has been associated with metachronous gastric cancer (MGC). The cancer-specific methylation gene, cysteine dioxygenase type 1 (CDO1), has been implicated in the occurrence of residual gastric cancer. We evaluated whether DNA methylation of CDO1 could be a predictive biomarker of MGC using specimens of MGC developing on scars after endoscopic submucosal dissection (ESD). Materials and Methods: CDO1 methylation values (TaqMeth values) were compared between 33 patients with early gastric cancer (EGC) with no confirmed metachronous lesions at >3 years after ESD (non-MGC: nMGC group) and 11 patients with MGC developing on scars after ESD (MGCSE groups: EGC at the first ESD [MGCSE-1 group], EGC at the second ESD for treating MGC developing on scars after ESD [MGCSE-2 group]). Each EGC specimen was measured at five locations (at tumor [T] and the 4-point tumor-adjacent noncancerous mucosa [TAM]). Results: In the nMGC group, the TaqMeth values for T were significantly higher than that for TAM (P=0.0006). In the MGCSE groups, TAM (MGCSE-1) exhibited significantly higher TaqMeth values than TAM (nMGC) (P<0.0001) and TAM (MGCSE-2) (P=0.0041), suggesting that TAM (MGCSE-1) exhibited CDO1 hypermethylation similar to T (P=0.3638). The area under the curve for discriminating the highest TaqMeth value of TAM (MGCSE-1) from that of TAM (nMGC) was 0.81, and using the cut-off value of 43.4, CDO1 hypermethylation effectively enriched the MGCSE groups (P<0.0001). Conclusions CDO1 hypermethylation has been implicated in the occurrence of MGC, suggesting its potential as a promising MGC predictor.

Background/Aims: Multiple white and flat elevated lesions (MWFL) that develop from the gastric corpus to the fornix may be strongly associated with oral antacid intake. Therefore, this study aimed to determine the association between the occurrence of MWFL and oral proton pump inhibitor (PPI) intake and clarify the endoscopic and clinicopathological characteristics of MWFL. Methods: The study included 163 patients. The history of oral drug intake was collected, and serum gastrin levels and anti-Helicobacter pylori immunoglobulin G antibody titers were measured. Upper gastrointestinal endoscopy was performed. The primary study endpoint was the association between MWFL and oral PPI intake. Results: In the univariate analyses, MWFL were observed in 35 (49.3%) of 71 patients who received oral PPIs and 10 (10.9%) of 92 patients who did not receive oral PPIs. The occurrence of MWFL was significantly higher among patients who received PPIs than in those who did not (p<0.001). Moreover, the occurrence of MWFL was significantly higher in patients with hypergastrinemia (p=0.005). In the multivariate analyses, oral PPI intake was the only significant independent factor associated with the presence of MWFL (p=0.001; odds ratio, 5.78; 95% confidence interval, 2.06–16.2). Conclusions Our findings suggest that oral PPI intake is associated with the presence of MWFL (UMINCTR 000030144).

Background/Aims: Image-enhanced endoscopy can detect superficial oro-hypopharyngeal squamous cell carcinoma; however, reliable endoscopy of the pharyngeal region is challenging. Endoscopy under general anesthesia during transoral surgery occasionally reveals multiple synchronous lesions that remained undetected on preoperative endoscopy. Therefore, we aimed to determine the lesion detection capability of endoscopy under general anesthesia for superficial oro-hypopharyngeal squamous cell carcinoma. Methods: This retrospective study included 63 patients who underwent transoral surgery for superficial oropharyngeal squamous cell carcinoma between April 2005 and December 2020. The primary endpoint was to compare the lesion detection capabilities of preoperative endoscopy and endoscopy under general anesthesia. Other endpoints included the comparison of clinicopathological findings between lesions detected using preoperative endoscopy and those newly detected using endoscopy under general anesthesia. Results: Fifty-eight patients (85 lesions) were analyzed. The mean number of lesions per patient detected was 1.17 for preoperative endoscopy and 1.47 for endoscopy under general anesthesia. Endoscopy under general anesthesia helped detect more lesions than preoperative endoscopy did (p<0.001). The lesions that were newly detected on endoscopy under general anesthesia were small and characterized by few changes in color and surface ruggedness. Conclusions Endoscopy under general anesthesia for superficial squamous cell carcinoma is helpful for detecting multiple synchronous lesions.