Factors determining the resection ability of snares in cold snare polypectomy: Construction of an ex vivo model for accurately evaluating resection ability

OBJECTIVES

Cold snare polypectomy (CSP)-dedicated snares (DSs) may have a higher resection ability than conventional snares. However, a model that can accurately and objectively evaluate and compare the resection ability of each snare has yet to be determined, and characteristics of snare parts that increase resection ability remain unknown. Therefore, we elucidated DSs' resection ability and all characteristics of the parts required for acquiring high resection ability.

METHODS

An ex vivo model for evaluating resection ability was generated using human colons obtained from forensic autopsy specimens. The force required to resect a 15 mm wide human colonic mucosa (FRR) was measured using this model; if the FRR is small, the resection ability is high. Next, after measuring the stiffness of each snare part, the correlation between the stiffness and resection ability was analyzed.

RESULTS

The force required to resect using SnareMaster Plus, Micro-Tech Cold Snare, Captivator Cold, Exacto Cold Snare, or Captivator II was 13.6 ± 1.0, 12.5 ± 1.2, 7.4 ± 1.2, 6.5 ± 1.0, and 28.7 ± 3.7 N, respectively. All DSs had significantly lower FRR than the conventional snare (Captivator II) and had higher resection ability (P < 0.001). A negative correlation was found between FRR and sheath or wire spindle stiffness, with correlation coefficients of 0.72 (P = 0.042) or 0.94 (P < 0.001), respectively. Moreover, 1 × 7 type wire rings had significantly higher friction coefficients than 1 × 3 type wire rings (P < 0.002).

CONCLUSION

Sheath and wire spindle stiffness should be increased to increase resection ability; 1 × 7 type wire rings may be suitable for CSP-snare parts.

Detailed Superiority of the CAD EYE Artificial Intelligence System over Endoscopists for Lesion Detection and Characterization Using Unique Movie Sets

Objectives

Detailed superiority of CAD EYE (Fujifilm, Tokyo, Japan), an artificial intelligence for polyp detection/diagnosis, compared to endoscopists is not well examined. We examined endoscopist's ability using movie sets of colorectal lesions which were detected and diagnosed by CAD EYE accurately.

Methods

Consecutive lesions of ≤10 mm were examined live by CAD EYE from March-June 2022 in our institution. Short unique movie sets of each lesion with and without CAD EYE were recorded simultaneously using two recorders for detection under white light imaging (WLI) and linked color imaging (LCI) and diagnosis under blue laser/light imaging (BLI). Excluding inappropriate movies, 100 lesions detected and diagnosed with CAD EYE accurately were evaluated. Movies without CAD EYE were evaluated first by three trainees and three experts. Subsequently, movies with CAD EYE were examined. The rates of accurate detection and diagnosis were evaluated for both movie sets.

Results

Among 100 lesions (mean size: 4.7±2.6 mm; 67 neoplastic/33 hyperplastic), mean accurate detection rates of movies without or with CAD EYE were 78.7%/96.7% under WLI (p<0.01) and 91.3%/97.3% under LCI (p<0.01) for trainees and 85.3%/99.0% under WLI (p<0.01) and 92.6%/99.3% under LCI (p<0.01) for experts. Mean accurate diagnosis rates of movies without or with CAD EYE for BLI were 85.3%/100% for trainees (p<0.01) and 92.3%/100% for experts (p<0.01), respectively. The significant risk factors of not-detected lesions for trainees were right-sided, hyperplastic, not-reddish, in the corner, halation, and inadequate bowel preparation.

Conclusions

Unique movie sets with and without CAD EYE could suggest it's efficacy for lesion detection/diagnosis.

Analysis of the characteristics of coexisting lesions in colorectal cancer patients in an international study: A subgroup analysis of the ATLAS trial

INTRODUCTION

We investigated coexisting lesion types in patients with invasive colorectal cancer (CRC) in a multinational study for comprehending the adenoma-carcinoma and serrated pathway about the development of CRC.

METHODS

We retrospectively reviewed 3050 patients enrolled in the international randomized controlled trial (ATLAS study) to evaluate the colorectal polyp detection performance of image-enhanced endoscopy in 11 institutions in four Asian countries/regions. In the current study, as a subgroup analysis of the ATLAS study, 92 CRC patients were extracted and compared to 2958 patients without CRC to examine the effects of age, sex, and coexisting lesion types (high-grade adenoma [HGA], low-grade adenoma with villous component [LGAV], 10 adenomas, adenoma ≥10 mm, sessile serrated lesions [SSL], and SSL with dysplasia [SSLD]). Additional analyses of coexisting lesion types were performed according to sex and location of CRC (right- or left-sided).

RESULTS

A multivariate analysis showed that HGA (odds ratio [95%confidence interval] 4.29 [2.16-8.18]; p<0.01), LGAV (3.02 [1.16-7.83], p=0.02) and age (1.04 [1.01-1.06], p=0.01) were independently associated with CRC. According to sex, the coexisting lesion types significantly associated with CRC were LGAV (5.58 [1.94-16.0], p<0.01) and HGA (4.46 [1.95-10.20], p<0.01) in males and HGA (4.82 [1.47-15.80], p<0.01) in females. Regarding the location of CRC, SSLD (21.9 [1.31-365.0], p=0.03) was significant for right-sided CRC, and HGA (5.22 [2.39-11.4], p<0.01) and LGAV (3.46 [1.13-10.6], p=0.02) were significant for left-sided CRC.

CONCLUSIONS

The significant coexisting lesions in CRC differed according to sex and location. These findings may contribute to comprehending the pathogenesis of CRC.

Linked color imaging improves colorectal lesion detection especially for low performance endoscopists: An international trial in Asia

BACKGROUND AND AIM

Linked color imaging (LCI) is an image-enhanced endoscopy technique that accentuates the color difference between red and white, potentially improving the adenoma detection rate (ADR). However, it remains unclear whether LCI performance in detecting colorectal lesions differs based on endoscopists' experience levels. We aimed to evaluate the differences in LCI efficacy based on the experience levels of endoscopists by conducting an exploratory analysis.

METHODS

In this post hoc analysis of an international randomized controlled trial comparing the detection of adenoma and other lesions using colonoscopy with LCI and high-definition white light imaging (WLI), we included patients from 11 institutions across four countries/regions: Japan, Thailand, Taiwan, and Singapore. We retrospectively reviewed differences in the lesion detection of LCI according to endoscopists' colonoscopy history or ADR.

RESULTS

We included 1692 and 1138 patients who underwent colonoscopies performed by 54 experts (experience of ≥ 5000 colonoscopies) and by 43 non-experts (experience of < 5000 colonoscopies), respectively. Both expert and non-expert groups showed a significant improvement in ADR with LCI compared to WLI (expert, 61.7% vs 46.4%; P < 0.001; non-expert, 56.6% vs 46.4%; P < 0.001). LCI had no effect on sessile serrated lesion detection rate in non-experts (3.1% vs 2.5%; P = 0.518). LCI significantly improved detection rates in endoscopists with relatively low detection performance, defined as an ADR < 50%.

CONCLUSIONS

This exploratory study analyzed data from a previous trial and revealed that LCI is useful for both experts and non-experts and is even more beneficial for endoscopists with relatively low detection performance using WLI.

Comparison of blue laser imaging and light-emitting diode-blue light imaging for the characterization of colorectal polyps using the Japan narrow-band imaging expert team classification: The LASEREO and ELUXEO COLonoscopic study

Objectives

Although the laser light is optically ideal for producing narrow-band light, it has not been used in some areas of the world. Endoscopic light sources using light-emitting diodes (LEDs) are used worldwide. The purpose of this study was to compare blue laser imaging (laser-BLI) and LED-blue light imaging (LED-BLI) for the characterization of colorectal polyps using the Japan narrow band imaging expert team (JNET) classification.

Methods

Colorectal lesions were prospectively examined using magnifying narrow-band light generated by a laser (laser-BLI) or LEDs (LED-BLI). Twelve endoscopists (six non-experts and six experts from three institutions) evaluated each still-magnified image of lesions using the JNET classification.

Results

Seven hundred and fifty-six images from 63 lesions were reviewed. The mean polyp size was 24.5 ± 13.4 mm. Histopathology included 13 serrated lesions and 50 neoplasms. The rate of agreement between laser-BLI and LED-BLI using the JNET classification was 92.5% (699/756). The weighted κ-statistic was 0.99. The percentages of "almost similar" comparing scores of surface patterns, vessel patterns, and brightness among all endoscopists were 95.4%, 95.9%, and 95.0%, respectively.

Conclusions

This multicenter study demonstrates that the rate of agreement between laser-BLI and LED-BLI using the JNET Classification is very high. The surface patterns, vessel patterns, and brightness are almost similar.

Short- and long-term outcomes of endoscopic submucosal dissection and laparoscopic and endoscopic cooperative surgery for superficial non-ampullary duodenal epithelial tumors

BACKGROUND AND AIMS

This retrospective study aimed to compare the short- and long-term outcomes of endoscopic submucosal dissection and laparoscopic and endoscopic cooperative surgery in patients with superficial non-ampullary duodenal epithelial tumors.

PATIENTS AND METHODS

We investigated consecutive patients with SNADETs > 10 mm in size who underwent ESD (ESD group) or LECS (LECS group) between January 2015 and March 2021. The data was used to analyze the clinical course, management, survival status, and recurrence between the two groups.

RESULTS

A total of 113 patients (100 and 13 in the ESD and LECS groups, respectively) were investigated. The rates of en bloc resection and curative resection were 100% vs. 100% and 93.0% vs. 77.0% in the ESD and LECS groups, respectively, with no significant difference. The ESD group had shorter resection and suturing times than the LECS group, but there were no significant difference after propensity score matching. There were also no differences in the rates of postoperative adverse event (7.0% vs. 23.1%; P = 0.161). The 3-year overall survival (OS) rate was high in both the ESD and LECS groups (97.6% vs. 100%; P = 0.334). One patient in the ESD group experienced recurrence due to liver metastasis; however, no deaths related to SNADETs were observed.

CONCLUSION

ESD and LECS are both acceptable treatments for SNADETs in terms of a high OS rate and a low long-term recurrence rate, thereby achieving a comparable high rate of curative resection. Further studies are necessary to compare the outcomes of ESD and LECS for SNADETs once both techniques are developed further.

Prevalence of colonoscopy in Japan using a large-scale health claims data compared to esophagogastroduodenoscopy

OBJECTIVE

Prevalence of colonoscopy (CS) is an important countermeasure against colorectal cancer (CRC). In this study, we used large-scale data for a comparison of CS with esophagogastroduodenoscopy (EGD) in Japan.

METHODS

This was a retrospective descriptive study. Commercially anonymized patient data were collected from various health insurance societies (JMDC, Inc. Tokyo, Japan) generated from the insurance registry, receipts (inpatient, outpatient, and prescription), and health checkup data. The data also included healthy subjects who had never been examined in a hospital. The data of 2,760,048 persons who were 50-75 years old during January 2012-December 2019 were extracted from the original data source. The annual rate, the prevalence rate (frequency of those undergoing at least one endoscopy during the period), and the percentage of repeaters (undergoing endoscopy at least twice during the period) of CS were calculated and compared to those of EGD.

RESULTS

The annual rates in 2012/2015/2019 were 3.4%/4.5%/5.3% for CS, respectively, and increased gradually from 2012 to 2019. Those rates were 7.0%/7.9%/7.4% for EGD, respectively, and did not increase. The prevalence rates of CS and EGD were 25.3% and 36.2%, respectively, among the 137,246 participants over 8 years. The prevalence rates of individuals in their 50 s/60 s/70 s were 23.0%/25.9%/31.4% for CS and 33.0%/37.6%/40.7% for EGD, respectively. The proportions of males/females were 27.9%/20.7% for CS, and 36.4%/35.8% for EGD, respectively. The repeat rates of CS and EGD were 40.3% and 44.8%, respectively, over 8 years.

CONCLUSIONS

Using large-scale data, we determined the status of CS and EGD in Japan.

Prognostic value of moderate or massive ascites in patients with advanced gastric cancer

Advanced gastric cancer is a highly aggressive malignancy. The available literature does not provide the prognostic value of ascites based on their degree, because most clinical trials exclude patients who present with massive ascites. Therefore, this study examined whether the presence or degree of ascites has a prognostic value in 124 patients with advanced gastric cancer. The degree of ascites was assessed using computed tomography and classified as none, small, moderate or massive. The overall survival (OS) was compared based on the presence or degree of ascites. Furthermore, a Cox proportional hazards analysis was performed to ascertain the predictors of OS. The cumulative 1-year and 2-year OS rates in patients without ascites were 43.5 and 20.2%, respectively, whereas those in patients with ascites were 29.1 and 13.6%, respectively (P=0.116). The cumulative 1-year and 2-year OS rates in patients without moderate or massive ascites were 39.5 and 20.9%, respectively; however, those in patients with moderate or massive ascites were 28.0 and 4.0%, respectively (P=0.027). Multivariate analysis showed that diffuse-type [hazard ratio (HR), 1.532; 95% confidence interval (CI), 1.002-2.343; P=0.049], moderate or massive ascites (HR, 2.153; 95% CI, 1.301-3.564; P=0.003) and chemotherapy (HR, 0.189; 95% CI, 0.101-0.352; P<0.001) were significant predictive factors of OS. In conclusion, the present study indicated that moderate or massive ascites may influence the OS of patients with advanced gastric cancer.

Multiple duodenal epithelial tumors in a patient with polymerase proofreading-associated polyposis in POLE variant

Polymerase proofreading-associated polyposis (PPAP) is a rare disease with autosomal-dominant inheritance caused by germline variants in the POLE and POLD1 genes. PPAP has been reported to increase the risk of multiple cancers, including colon, duodenal, and endometrial cancers. Herein, we report a case in which multiple duodenal tumors led to the detection of a POLE mutation. A 43-year-old woman underwent esophagogastroduodenoscopy (EGD). Multiple duodenal tumors were detected, and all lesions were treated endoscopically. The patient had a history of multiple colorectal cancers and endometrial cancer along with a family history of cancer; hence, genetic testing was performed, and POLE variant, c.1270C > G (p.Leu424Val) was detected. Hereditary colorectal cancer syndromes should be considered in patients with colorectal cancer who have multiple cancers or a family history of cancer, and multigene panel sequencing is useful in confirming the diagnosis. In addition, duodenal tumors frequently coexist in patients with PPAP-carrying POLE variants, while the endoscopic treatment for duodenal tumors becomes safe and useful with several new approaches. Therefore, surveillance EGD is necessary in such patients for the early detection and treatment of duodenal tumors.

Conventional versus underwater endoscopic resection for superficial non-ampullary duodenal epithelial tumours

BACKGROUND AND OBJECTIVE

Several endoscopic resection methods have been developed as less invasive treatments for superficial non-ampullary duodenal epithelial tumours. This study aimed to compare outcomes of conventional endoscopic mucosal resection and underwater endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours, including resection depth and rate of the muscularis mucosa contained under the lesion.

METHODS

This single-centre retrospective cohort study conducted from January 2009 to December 2021 enrolled patients who underwent conventional endoscopic mucosal resection and underwater endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours and investigated their clinicopathological outcomes using propensity score matching.

RESULTS

Of the 285 superficial non-ampullary duodenal epithelial tumours, 98 conventional endoscopic mucosal resections and 187 underwater endoscopic mucosal resections were included. After propensity score matching, 64 conventional endoscopic mucosal resections and 64 underwater endoscopic mucosal resections were analysed. The R0 resection rate was significantly higher in underwater endoscopic mucosal resection cases than in conventional endoscopic mucosal resection cases (70.3% vs. 50.0%; P = 0.030). In the multivariate analysis, a lesion diameter > 10 mm (odds ratio 7.246; P = 0.001), being in the 1st-50th treatment period (odds ratio 3.405; P = 0.008), and undergoing conventional endoscopic mucosal resection (odds ratio 3.617; P = 0.016) were associated with RX/R1 resection. Furthermore, in underwater endoscopic mucosal resection cases, the R0 rate was significantly higher for lesions diameter ≤10 mm than >10 mm, and was significantly higher in the 51st-treatment period than in the 1st-50th period. Conventional endoscopic mucosal resection and underwater endoscopic mucosal resection cases showed no significant difference in resection depth and muscularis mucosa containing rate.

CONCLUSIONS

Underwater endoscopic mucosal resection may be more acceptable than conventional endoscopic mucosal resection for superficial non-ampullary duodenal epithelial tumours ≤ 10 mm. A steep early learning curve may be acquired for underwater endoscopic mucosal resection. Large multicentre prospective studies need to be conducted to confirm the effectiveness of underwater endoscopic mucosal resection.

An Analysis of Delayed Bleeding in Cases of Colorectal Endoscopic Submucosal Dissection Due to Types of Direct Oral Anticoagulants in Japan

BACKGROUND & AIMS

Reported rates of delayed bleeding (DB) after endoscopic resection using direct oral anticoagulants (DOACs) are high and heterogeneous. This large-scale multicenter study analyzed cases of DB after colorectal endoscopic submucosal dissection related to various types of DOACs in Japan (the ABCD-J study) with those associated with warfarin.

METHODS

We retrospectively reviewed 1019 lesions in patients treated with DOACs and 459 lesions in patients treated with warfarin among 34,455 endoscopic submucosal dissection cases from 47 Japanese institutions between 2012 and 2021. The DB rate (DBR) with each DOAC was compared with that with warfarin. Risk factors for DB in patients treated with DOACs or warfarin were also investigated.

RESULTS

The mean tumor sizes in the DOAC and warfarin groups were 29.6 ± 14.0 and 30.3 ± 16.4 mm, respectively. In the DOAC group, the DBR with dabigatran (18.26%) was significantly higher than that with apixaban (10.08%, P = .029), edoxaban (7.73%, P = .001), and rivaroxaban (7.21%, P < .001). Only rivaroxaban showed a significantly lower DBR than warfarin (11.76%, P = .033). In the multivariate analysis, heparin bridging therapy (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.27-3.73, P = .005), rectal location (2.01, 1.28-3.16, P = .002), and procedure time ≥55 minutes (2.43, 1.49-3.95, P < .001) were significant risk factors for DB in the DOAC group. The DB risk in the DOAC group (OR, (95% CI)) was 2.13 (1.30-3.50) and 4.53 (2.52-8.15) for 1 and 2 significant risk factors, respectively.

CONCLUSIONS

Dabigatran was associated with a higher DBR than other DOACs, and only rivaroxaban was associated with a significantly lower DBR than warfarin.

Underwater clip closure method for mucosal defects after duodenal endoscopic submucosal dissection (with video)

Conventional clip closure of mucosal defects after duodenal endoscopic submucosal dissection decreases the incidence of delayed adverse events, but may result in incomplete closure, depending on size or location. This study aimed to assess the effectiveness of the underwater clip closure method for complete duodenal defect closure without the difficulties associated with conventional closure methods. We investigated 19 patients with 20 lesions who underwent endoscopic submucosal dissection of the duodenum and subsequent mucosal defect closure in underwater conditions at our facility between February 2021 and January 2022. The success rate of the underwater clip closure method was defined as the complete endoscopic closure of the mucosal defect; a success rate of 100% was achieved. The median resected specimen size was 34.3 mm, the median procedure time for mucosal defect closure was 14 min, and the median number of clips used per patient was 12. No delayed adverse events were observed. The underwater clip closure method is a feasible option for complete closure of mucosal defects, regardless of the size or location of a duodenal endoscopic submucosal dissection.

Efficacy of Glycicumarin and Isoliquiritigenin in Suppressing Colonic Peristalsis in Both an Animal Model and a Clinical Trial

Patients with diarrhea-predominant irritable bowel syndrome (IBS-D) show excessive peristalsis, and antispasmodic agents may be useful therapeutic agents. There are few reports on the use of Kampo medicines for the treatment of IBS-D. Shakuyakukanzoto (SKT) is a Kampo medicine that is effective against abdominal pain. We examined the relationship between SKT and intestinal peristalsis in an animal model and a prospective study. In the animal model, SKT and its components were administered from the serosal side of the colon and colonic peristalsis was evaluated using intraluminal pressure and spatiotemporal mapping before and after the administration of SKT and its components. In this clinical trial, we used abdominal ultrasonography (US) to obtain long-axis images of the sigmoid colon of 11 patients. The frequency of intestinal peristalsis was measured using US in five patients with SKT and six patients without medication after the ingestion of a test meal. The primary outcome was the frequency of peristalsis. The Clinical Trial Registry Website (Trial No. UMIN-CTR; UMIN000051547). In the animal model, peony did not suppress peristalsis frequency, but SKT (p = 0.005) and glycyrrhiza (p = 0.001) significantly suppressed peristalsis frequency compared with saline and peony. Among the glycyrrhiza components, glycycoumarin and isoliquiritigenin suppressed the peristalsis frequency compared to dimethyl sulfoxide (control) (p = 0.001, 0.01, respectively). In a clinical trial, peristalsis was significantly suppressed after oral administration in patients taking SKT (p = 0.03). Administration of SKT was found to inhibit colonic peristalsis, with glycicumarin and isoliquiritigenin being particularly relevant among its components.

Efficacy of hemostatic gel for perioperative bleeding and prevention of delayed bleeding of cold snare polypectomy under anticoagulant

Background and Aim

A hemostatic gel, PuraStat (3-D Matrix, Tokyo, Japan), is used for various gastrointestinal hemostasis. In this study, we analyzed the efficacy of PuraStat for perioperative bleeding (POB) and prevention of delayed bleeding (DB) to colorectal cold snare polypectomy (CSP) with continuous anticoagulant.

Methods

This was a single-center, retrospective study. Subjects were lesions of 2-9 mm under continuous anticoagulant from 2021 to 2023 and treated with PuraStat for POB. The definition of POB was bleeding which did not stop spontaneously by 1.0-1.5 min after resection and needed hemostasis. Successful hemostasis was defined as cessation of bleeding within 1.0-1.5 min after spraying PuraStat and the rate of it and risk factors of POB were analyzed. For comparison, cases receiving previous CSP without PuraStat were extracted from all cases with CSP (2018-2021), and POB and DB rate (DBR) were analyzed after propensity score matching.

Results

One hundred twenty-two lesions (91: direct oral anticoagulant (DOAC), 31: warfarin) with anticoagulant were analyzed and the rate of successful hemostasis with PuraStat was 92.6% (DOAC/warfarin: 93.4%/80.6%, P = 0.01). The rate of DB was 0.0%. Multivariate analysis showed that significant risk factors about unsuccessful hemostasis for POB with PuraStat were lesion size 8-9 mm (P < 0.01), warfarin (P = 0.01), and combination of antiplatelet (P = 0.01). Regarding the comparison about CSP with/without PuraStat, the clipping rate and DBR were 8.5%/94.9% (P < 0.01) and 0%/1.7% (P = 1.0).

Conclusion

The effects of PuraStat for POB and DB in colorectal CSP with continuous anticoagulant were acceptable.

Characteristics of Gastric Mucosa-Associated Microbiota in Patients with Early Gastric Cancer After Successful Helicobacter pylori Eradication

BACKGROUND

Helicobacter pylori (H. pylori) is widely recognized as a definite carcinogen in gastric cancer (GC). Although H. pylori eradication reduces the risk of GC, GC recurrence has been detected even after successful H. pylori eradication. Recently, the analysis of gut microbiota was reported.

AIMS

This study aimed to evaluate the correlation between gastric mucosa-associated microbiota (G-MAM) and early gastric cancer (EGC) after successful H. pylori eradication.

METHODS

In this pilot study, G-MAM were collected during the esophagogastroduodenoscopy of 17 patients, receiving H. pylori eradication therapy at least 5 years ago. The patients were divided into those with EGC (the EGC group, 8 patients) and those without EGC (the NGC group, 9 patients). Microbial samples in the greater curvature of the pyloric site were obtained using an endoscopic cytology brush, and the G-MAM profiles of each sample were analyzed using 16S rRNA V3-V4 gene sequencing.

RESULTS

Between the two groups, there was no significant difference in the median age, sex, median period after successful eradication of H. pylori, the α diversity, and the average abundance at the phylum level. At the genus level, the average abundance of Unclassified Oxalobacteraceae, Capnocytophaga, and Haemophilus was significantly lower in the EGC group than in the NGC group (0.89 vs. 0.14%, P < 0.01, 0.28 vs. 0.00%, P < 0.01 and 5.84 vs. 2.16%, P = 0.034, respectively).

CONCLUSIONS

We demonstrated alternations in the profiles of G-MAM between the two groups. Our results suggest that G-MAM may influence carcinogenesis after successful H. pylori eradication.

Short-term outcomes of endoscopic resection for colorectal neuroendocrine tumors: Japanese multicenter prospective C-NET STUDY

OBJECTIVES

The incidence of colorectal neuroendocrine tumors (NETs) has increased with colorectal cancer screening programs and increased colonoscopies. The management of colorectal NETs has recently shifted from radical surgery to endoscopic resection. We aimed to evaluate the short-term outcomes of various methods of endoscopic resection for colorectal NETs.

METHODS

Among those registered in the C-NET STUDY, patients with colorectal NETs who underwent endoscopic treatment as the initial therapy were included. Short-term outcomes, such as the en bloc resection rate and R0 resection (en bloc resection with tumor-free margin) rate, were analyzed based on treatment modalities.

RESULTS

A total of 472 patients with 477 colorectal NETs received endoscopic treatment. Of these, 418 patients with 421 lesions who met the eligibility criteria were included in the analysis. The median age of the patients was 55 years, and 56.9% of them were men. The lower rectum was the most commonly affected site (88.6%), and lesions <10 mm accounted for 87% of the cases. Endoscopic submucosal resection with a ligation device (ESMR-L, 56.5%) was the most common method, followed by endoscopic submucosal dissection (ESD, 31.4%) and endoscopic mucosal resection using a cap (EMR-C, 8.5%). R0 resection rates <10 mm were 95.5%, 94.8%, and 94.3% for ESMR-L, ESD, and EMR-C, respectively. All 16 (3.8%) patients who developed treatment-related complications could be treated conservatively. Overall, 23 (5.5%) patients had incomplete resection without independent clinicopathological risk factors.

CONCLUSION

ESMR-L, ESD, and EMR-C were equally effective and safe for colorectal NETs with a diameter <10 mm.

Effectiveness of endoscopic resection for colorectal neoplasms in ulcerative colitis: a multicenter registration study

BACKGROUND AND AIMS

Patients with ulcerative colitis (UC) are at risk of developing colorectal cancer. The feasibility of endoscopic resection (ER) for UC-associated neoplasia has been suggested, but its efficacy and safety remain unclear. We aimed to assess the efficacy and safety of ER for colorectal neoplasms in patients with UC.

METHODS

This was a retrospective, multicenter cohort study of patients with UC who initially underwent ER or surgery for colorectal neoplasms between April 2015 and March 2021. Patients who had prior colorectal neoplastic lesions were excluded.

RESULTS

Among 213 men and 123 women analyzed, the mean age at UC onset was 41.6 years, and the mean age at neoplasia diagnosis was 56.1 years for 240 cases of total colitis, 59 cases of left-sided colitis, 31 cases of proctitis, and 6 cases of segmental colitis. EMR was performed for 142 lesions, and endoscopic submucosal dissection (ESD) was performed for 96 lesions. The perforation rate was 2.5% for all 238 lesions removed by ER and 6.3% for the 96 lesions removed by ESD. Among 146 ER lesions followed up with endoscopy, the local recurrence rate was 2.7%. The incidence of metachronous neoplasia after ER was 6.1%. All patients were followed a median of 34.7 months after initial treatment, and 5 died (all surgical cases). Overall survival was significantly higher in the ER group than in the surgery group (P = .0085).

CONCLUSIONS

ER for colorectal neoplasms in UC may be acceptable in selected cases, although follow-up for metachronous lesions is necessary.

Analysis of the development of gastric cancer after resecting colorectal lesions using large-scale health insurance claims data

BACKGROUND

Colorectal endoscopic resection (C-ER) is spreading due to the increase of colorectal cancer (CRC) in Japan. Gastric cancer (GC) sometimes occurs after C-ER. We aimed to analyze the status of GC after C-ER using large-scale data.

METHODS

We retrospectively used commercially anonymized health insurance claims data of 5.71 million patients from 2005 to 2018, and extracted 62,392 patients ≥ 50 years old who received C-ER. The incidence and risk factors of GC were analyzed. Additionally, subjects were divided into ≥ 2 cm group and < 2 cm group and risks of GC were analyzed.

RESULTS

The median age (range) was 58 (50-75) years and the overall rate of GC was 0.68% (423/62,392). Multivariate analysis showed that significant risk factors for GC [odds rates (OR), 95% confidence interval (CI)] were colorectal lesion size ≥ 2 cm (1.75, 1.24-2.47, p = 0.002), age ≥ 65 y.o. (1.65, 1.31-2.07, p < 0.001), male (2.35, 1. 76-3.13, p < 0.001), diabetes mellitus (1.40, 1.02-1.92, p = 0.035), liver disease (1.54, 1.06-2.24, p = 0.025), Helicobacter pylori infection (2.10, 1.65-2.67, p < 0.001), chronic atrophic gastritis (1.58, 1.14-2.18, p = 0.006), and CRC (1.72, 1.10-2.68, p = 0.017). The rate of GC in the ≥ 2 cm was significantly higher than that in < 2 cm groups (1.17% and 0.65%, p < 0.001). According to the number of significant risk factors, the rates of GC and the hazard ratios of GC (95%CI) were 0.64% and 3.64 (2.20-6.02) and 1.95% and 11.17 (6.57-19.00) for patient with 1-2 and ≥ 3 risk factors, compared with patients without risk factors.

CONCLUSIONS

Using large-scale data, risk factors for GC, including colorecal lesions ≥ 2 cm after C-ER could be investigated.

Additional 30-Second Observation of the Right-Sided Colon for Missed Polyp Detection With Texture and Color Enhancement Imaging Compared with Narrow Band Imaging: A Randomized Trial

INTRODUCTION

The efficacy of texture and color enhancement imaging (TXI) in the novel light-emitting diode endoscopic system for polyp detection has not been examined. We aimed to evaluate the noninferiority of the additional 30-second (Add-30-s) observation of the right-sided colon (cecum/ascending colon) with TXI compared with narrow band imaging (NBI) for detecting missed polyps.

METHODS

We enrolled 381 patients ≥40 years old who underwent colonoscopy from September 2021 to June 2022 in 3 institutions and randomly assigned them to either the TXI or NBI groups. The right-sided colon was first observed with white light imaging in both groups. Second, after reinsertion from hepatic flexure to the cecum, the right-sided colon was observed with Add-30-s observation of either TXI or NBI. The primary endpoint was to examine the noninferiority of TXI to NBI using the mean number of adenomas and sessile serrated lesions per patient. The secondary ones were to examine adenoma detection rate, adenoma and sessile serrated lesions detection rates, and polyp detection rates in both groups.

RESULTS

The TXI and NBI groups consisted of 177 and 181 patients, respectively, and the noninferiorities of the mean number of adenomas and sessile serrated lesions per patients in the second observation were significant (TXI 0.29 [51/177] vs NBI 0.30 [54/181], P < 0.01). The change in adenoma detection rate, adenoma and sessile serrated lesions detection rate, and polyp detection rate for the right-sided colon between the TXI and NBI groups were not different (10.2%/10.5% [ P = 0.81], 13.0%/12.7% [ P = 0.71], and 15.3%/13.8% [ P = 0.71]), respectively.

DISCUSSION

Regarding Add-30-s observation of the right-sided colon, TXI was noninferior to NBI.

Comparison of LED and LASER Colonoscopy About Linked Color Imaging and Blue Laser/Light Imaging of Colorectal Tumors in a Multinational Study

INTRODUCTION

In light-emitting diode (LED) and LASER colonoscopy, linked color imaging (LCI) and blue light/laser imaging (BLI) are used for lesion detection and characterization worldwide. We analyzed the difference of LCI and BLI images of colorectal lesions between LED and LASER in a multinational study.

METHODS

We prospectively observed lesions with white light imaging (WLI), LCI, and BLI using both LED and LASER colonoscopies from January 2020 to August 2021. Images were graded by 27 endoscopists from nine countries using the polyp visibility score: 4 (excellent), 3 (good), 2 (fair), and 1 (poor) and the comparison score (LED better/similar/LASER better) for WLI/LCI/BLI images of each lesion.

RESULTS

Finally, 32 lesions (polyp size: 20.0 ± 15.2 mm) including 9 serrated lesions, 13 adenomas, and 10 T1 cancers were evaluated. The polyp visibility scores of LCI/WLI for international and Japan-expert endoscopists were 3.17 ± 0.73/3.17 ± 0.79 (p = 0.92) and 3.34 ± 0.78/2.84 ± 1.22 (p < 0.01) for LED and 3.30 ± 0.71/3.12 ± 0.77 (p < 0.01) and 3.31 ± 0.82/2.78 ± 1.23 (p < 0.01) for LASER. Regarding the comparison of lesion visibility about between LED and LASER colonoscopy in international endoscopists, a significant difference was achieved not for WLI, but for LCI. The rates of LED better/similar/LASER better for brightness under WLI were 54.5%/31.6%/13.9% (International) and 75.0%/21.9%/3.1% (Japan expert). Those under LCI were 39.2%/35.4%/25.3% (International) and 31.3%/53.1%/15.6% (Japan expert). There were no significant differences in the diagnostic accuracy and the comparison score of BLI images between LED and LASER.

CONCLUSIONS

The differences of lesion visibility for WLI/LCI/BLI between LED and LASER in international endoscopists could be compared to those in Japanese endoscopists.

Astaxanthin attenuated the stress-induced intestinal motility disorder via altering the gut microbiota

Gut microbiota and short-chain fatty acids (SCFAs) are recognized as key factors in the pathophysiology of irritable bowel syndrome. Astaxanthin is a carotenoid with strong antioxidant and anti-inflammatory activities. In this study, we examined the effects of astaxanthin on gut microbiota-, SCFAs-, and corticotropin-releasing factor (CRH)-induced intestinal hypermotility. Male Wistar rats (n=12 per group) were fed a diet with or without 0. 02% (w/w) astaxanthin for four weeks and CRH or saline was administered intravenously. The number of fecal pellets was counted 2 h after injection. Then the rats were sacrificed, and the cecal content were collected 3 h after injection. The number of feces was significantly increased by CRH injection in the control group (2.0 vs. 6.5; p=0.028), but not in the astaxanthin group (1.0 vs. 2.2; p=0.229) (n=6 per group). The cecal microbiota in the astaxanthin group was significantly altered compared with that in the control group. The concentrations of acetic acid (81.1 μmol/g vs. 103.9 μmol/g; p=0.015) and butyric acid (13.4 μmol/g vs. 39.2 μmol/g; p<0.001) in the astaxanthin group were significantly lower than that in the control group (n=12 per group). Astaxanthin attenuates CRH-induced intestinal hypermotility and alters the composition of gut microbiota and SCFAs.

Effects and risk factors of TAS-102 in real-world patients with metastatic colorectal cancer, EROTAS-R study

BACKGROUND

Trifluridine/tipiracil (TAS-102) is an anticancer drug for metastatic colorectal cancer (CRC). This study aimed to analyze the effects and risk factors about effects of TAS-102 in real-world patients with metastatic CRC (the EROTAS-R study).

METHODS

This study retrospectively analyzed 271 patients aged ≥ 20 years who underwent TAS-102 for metastatic CRC at nine related institutions from 2014 to 2021. Therapeutic results of TAS-102 + bevacizumab (Bev) and TAS-102, effect predictors, adverse events (AE), and AE predictors were examined.

RESULTS

The backgrounds of all cases were as follows: average age, 66.7 ± 10.9 years; male ratio, 59.5%; performance status (PS) 0/1/2, 43.5%/50.6%/5.9%; and tumor site right/left, 25.5%/74.5%. The therapeutic results of 109 cases receiving TAS-102 + Bev and 162 cases receiving TAS-102 were as follows: disease control rate, 53.2% vs. 28.0% (p < 0.01); progressive free survival (PFS), 6.2 vs. 4.2 months (p < 0.01); and overall survival (S), 11.8 vs. 9.3 months (p = 0.03). Multivariate analysis for effect-related factors (odds ratio (OR), 95%confidence interval (CI)) showed the following: PS1 + 2 (0.257, 0.134-0.494, p < 0.01) and a combination of Bev (3.052, 1.598-5.827, p < 0.01). The rates of grade 3 AE for TAS-102 + Bev and TAS-102 were 53.2% and 48.8%, respectively (p = 0.47). Various AE predictors were as follows: male sex (p = 0.69), age ≥ 75 years (p = 0.59), PS1 + 2 (p = 0.20), body surface area < 1.53 m2 (p = 0.26), eGFR < 50 ml/min (p = 0.02), and AST ≥ 50 IU/L (p = 0.64).

CONCLUSION

A better OS and PFS comparing TAS-102 + Bev to TAS-102 for CRC was achieved in a large number of real-world patients.

The Efficacy of 480 ml Oral Sodium Sulfate for Improving Insufficient Bowel Preparation of Colonoscopy with High-Concentrated Polyethylene Glycol

Objectives

Oral sulfate solution (OSS) is used for bowel preparation (BP) during colonoscopy. The way of taking this agent can be used a same-day regimen (only on the day of colonoscopy) and split regimen (the day before and on the day of colonoscopy) for receiving it. In this study, we analyzed the efficacy of a same-day regimen of 480 ml OSS for insufficient bowel preparation (BP) with high-concentrated polyethylene glycol (H-PEG).

Materials and Methods

This multicenter retrospective study was conducted from December 2021 to December 2022 at three related institutions on patients aged ≥ 20 years with a fair or poor Aronchick score of BP with 1 l H-PEG in previous colonoscopy. All patients received a low-residual diet and 10 ml of 0.75% picosulfate sodium a day before the colonoscopy and 480 ml of OSS and ≥1 l of water 3 hours before the colonoscopy. We analyzed the rate of improvement with OSS compared to H-PEG and other efficacies, and adverse events (AE).

Results

We evaluated 125 cases (77 males) with an average age of 72.1 ± 8.8 years. The completion rate of 480 ml of OSS was 97.6% (122/125). The improvement rate of BP showing good or excellent score with OSS was 70.4% (88/125). Compared OSS with previous H-PEG, the insertion time (min) was 7.0 ± 4.8 vs. 8.1 ± 6.0 (p = 0.01), and the adenoma detection rates were 67.2% vs. 63.2% (p = 0.05). The cleansing time (min) was 131 ± 46 vs. 165 ± 53 (p < 0.01). The rate of AE with OSS was 10.4% (13/125). There were no significant differences about AE in age and gender. The tolerance of OSS compared with H-PEG (good/similar/bad) was 72.0%/24.8%/3.2% (amounts), 26.4%/39.2%/34.4% (taste), and 76.8%/10.4%/12.8% (overall preference), respectively.

Conclusions

The same-day regimen of 480 ml OSS effectively improved the insufficient BP of 1 l H-PEG.

Efficacy of a novel self-assembling peptide gel for initial hemostasis during cold snare polypectomy for multiple duodenal adenomas

Watch a video of this article.

Gastrointestinal Angiodysplasia in Patients with Severe Aortic Stenosis: The Endoscopic Features of Heyde's Syndrome

INTRODUCTION

Aortic stenosis (AS) is sometimes associated with gastrointestinal bleeding, and this phenomenon is known as Heyde's syndrome. Such bleeding is most often considered to originate from gastrointestinal angiodysplasias, but the frequency and endoscopic features of such bleeding remain unclear. This study aimed to determine the frequency and endoscopic features of gastrointestinal angiodysplasia in patients with severe AS.

PATIENTS AND METHODS

In this multicenter, retrospective study, we evaluated consecutive patients who underwent transcatheter aortic valve implantation (TAVI) with severe AS from May 2016 to December 2019. We extracted the data on the clinicopathological features according to the status of anemia, the proportion of patients who underwent gastrointestinal endoscopic examinations and demonstrated gastrointestinal angiodysplasia, and identified the endoscopic features associated with such patients.

RESULTS

In 325 patients, the rates of moderate/severe anemia (hemoglobin < 11 g/dL) were 52%. Regarding medicine, there were no significant differences between the patients with and without moderate/severe anemia. Patients were examined by esophagogastroduodenoscopy (21%), colonoscopy (12%), and balloon-assisted enteroscopy or small bowel capsule endoscopy (1.5%). Patients with moderate/severe anemia had significantly more angiodysplasia (38.3% vs. 7.7%; p < 0.0001) and active bleeding (23.4% vs. 0%; p < 0.01). Angiodysplasia was detected in 21 patients (stomach, n = 9; small intestine, n = 5, and colon, n = 10).

CONCLUSIONS

The results suggest, for the first time, that patients with severe AS who underwent TAVI and moderate/severe anemia frequently had gastrointestinal angiodysplasia and active bleeding throughout the entire gastrointestinal tract.

Computer-aided diagnosis of early-stage colorectal cancer using nonmagnified endoscopic white-light images (with videos)

BACKGROUND AND AIMS

Differentiation of colorectal cancers (CRCs) with deep submucosal invasion (T1b) from CRCs with superficial invasion (T1a) or no invasion (Tis) is not straightforward. This study aimed to develop a computer-aided diagnosis (CADx) system to establish the diagnosis of early-stage cancers using nonmagnified endoscopic white-light images alone.

METHODS

From 5108 images, 1513 lesions (Tis, 1074; T1a, 145; T1b, 294) were collected from 1470 patients at 10 academic hospitals and assigned to training and testing datasets (3:1). The ResNet-50 network was used as the backbone to extract features from images. Oversampling and focal loss were used to compensate class imbalance of the invasive stage. Diagnostic performance was assessed using the testing dataset including 403 CRCs with 1392 images. Two experts and 2 trainees read the identical testing dataset.

RESULTS

At a 90% cutoff for the per-lesion score, CADx showed the highest specificity of 94.4% (95% confidence interval [CI], 91.3-96.6), with 59.8% (95% CI, 48.3-70.4) sensitivity and 87.3% (95% CI, 83.7-90.4) accuracy. The area under the characteristic curve was 85.1% (95% CI, 79.9-90.4) for CADx, 88.2% (95% CI, 83.7-92.8) for expert 1, 85.9% (95% CI, 80.9-90.9) for expert 2, 77.0% (95% CI, 71.5-82.4) for trainee 1 (vs CADx; P = .0076), and 66.2% (95% CI, 60.6-71.9) for trainee 2 (P < .0001). The function was also confirmed on 9 short videos.

CONCLUSIONS

A CADx system developed with endoscopic white-light images showed excellent per-lesion specificity and accuracy for T1b lesion diagnosis, equivalent to experts and superior to trainees. (Clinical trial registration number: UMIN000037053.).

Linked-Color Imaging Detects More Colorectal Adenoma and Serrated Lesions: An International Randomized Controlled Trial

BACKGROUND & AIMS

Effects of linked-color imaging (LCI) on colorectal lesion detection and colonoscopy quality remain controversial. This study compared the detection rates of adenoma and other precursor lesions using LCI vs white-light imaging (WLI) during screening, diagnostic, and surveillance colonoscopies.

METHODS

This randomized controlled trial was performed at 11 institutions in 4 Asian countries/regions. Patients with abdominal symptoms, a primary screening colonoscopy, positive fecal immunochemical test results, or undergoing postpolypectomy surveillance were recruited and randomly assigned in a 1:1 ratio to either the LCI or high-definition WLI group. The primary outcome was adenoma detection rate (ADR). Secondary outcomes were polyp detection rate, advanced ADR, sessile serrated lesion (SSL) detection rate, and the mean number of adenomas per colonoscopy. The recommended surveillance schedule distribution after trial colonoscopy was analyzed.

RESULTS

Between November 2020 and January 2022, there were 3050 participants (LCI, n = 1527; WLI, n = 1523) recruited. The LCI group ADR was significantly higher than the WLI group ADR using intention-to-treat (58.7% vs 46.7%; P < .01) and per-protocol analyses (59.6% vs 46.4%; P < .01). The LCI group polyp detection rates (68.6% vs 59.5%; P < .01), SSL detection rates (4.8% vs 2.8%; P < .01), and adenomas per colonoscopy (1.48 vs 1.02; P < .01) also were significantly higher. However, the advanced ADR was not significantly different (13.2% vs 11.0%; P = .06). Significantly more patients in the LCI group had shorter recommended surveillance schedules than the WLI group (P < .01).

CONCLUSIONS

Compared with WLI, LCI improved adenoma and other polyp detection rates, including SSLs, resulting in alteration of the recommended surveillance schedule after screening, diagnostic, and postpolypectomy surveillance colonoscopies.

TRIAL REGISTRATION NUMBER

UMIN000042432 (https://www.umin.ac.jp/ctr/index.htm).

Abstract 1688: Proton pump inhibitors as a potential combination therapy with existing chemotherapy for esophageal cancer

Introduction: V-ATPase is highly expressed in cancer cells and has been shown to be involved in the transformation of normal cells into cancer cells, invasion of tissues, survival of cancer cells, and the formation of drug resistance. The use of proton pump inhibitors (PPIs) as V-ATPase inhibitors has been shown to enhance the efficacy of chemotherapy in some cancers.

Material and Method: We investigated the effect of proton pump inhibitors on esophageal squamous cell carcinoma, one of the major causes of cancer mortality in Japan. First, three PPIs at various concentrations (lansoprazole, esomeprazole, and bonoprazan) and pyrimidine fluoride (5-FU), a key drug in chemotherapy for esophageal cancer, were used as basic medical agents. Human esophageal squamous cell lines, KYSE50 and KYSE70, were prepared and treated with the above drugs, and cell viability assays were performed using Cell Counting Kit 8 for 72 hours. We then performed a retrospective clinical study of 40 patients with clinical stage IV esophageal squamous cell carcinoma treated with the drugs at Kyoto Prefectural University of Medicine Hospital in Japan.

Result: In cell survival assays, PPIs showed significantly enhanced cytotoxic effects of pyrimidine fluoride on all cell lines compared with those not treated with PPIs. Clinical data showed no difference in the incidence of treatment-related adverse events between the PPI and non-PPI groups. The response rate after two courses of chemotherapy was 66.7% in the PPI group and 40.9% in the non-PPI group (p=0.102). Kaplan-Meier analysis showed improved OS in patients treated with PPIs (log rank test p=0.032), and multivariate analysis showed that PPI use was associated with a more favorable OS (p=0.009,HR 0.33,95% CI 0.12-0.76 ).

Conclusion: In the chemotherapy of esophageal squamous cell carcinoma, the use of PPIs may enhance the cytotoxic effect of the key drug, pyrimidine fluoride, while ensuring safety, and may lead to better therapeutic efficacy.

Citation Format: Ryuichi Morita, Takeshi Ishikawa, Shinya Matsumura, Tomoki Sakakida, Juichiro Yoshida, Toshifumi Doi, Ryohei Hirose, Ken Inoue, Osamu Dohi, Naohisa Yoshida, Kazuhiko Uchiyama, Tomohisa Takagi, Hideyuki Konishi, Yuji Naito, Yoshito Itoh. Proton pump inhibitors as a potential combination therapy with existing chemotherapy for esophageal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1688.

LEARNING CURVE IN ESOPHAGEAL ENDOSCOPIC SUBMUCOSAL DISSECTION BY WESTERN ENDOSCOSPISTS TRAINED IN JAPAN: EXPERIENCE IN LATIN AMERICA

•This study aimed to assess the learning curve effect on patient's clinical outcome for EESD. Retrospective observational study, enrolling patients that underwent EESD from 2009 to 2021, divided in 2 groups. Mean procedure time was 111.8 min and 103.6 min for T1 and T2, respectively (P=0.004). The learning curve in esophageal ESD could be overcomed effectively and safely by an adequately trained Western endoscopist. Background - Esophageal endoscopic submucosal dissection (EESD) is a complex and time-consuming procedure at which training are mainly available in Japan. There is a paucity of data concerning the learning curve to master EESD by Western endoscopists. Objective - This study aimed to assess the learning curve effect on patient's clinical outcome for EESD. Methods - This is a retrospective observational study. Enrolling patients that underwent EESD from 2009 to 2021. The analysis was divided into two periods; T1: case 1 to 49 and T2: case 50 to 98. The following features were analyzed for each group: patients and tumors characteristics, en-bloc, complete and curative resection rates, procedure duration and adverse events rate. Results - Ninety-eight EESD procedures were performed. Mean procedure time was 111.8 min and 103.6 min for T1 and T2, respectively (P=0.004). En bloc resection rate was 93.8% and 97.9% for T1 and T2, respectively (P=0.307). Complete resection rate was 79.5% and 85.7% for T1 and T2, respectively (P=0.424). Curative resection rate was 65.3% and 71.4% for T1 and T2, respectively (P=0.258). Four patients had complications; three during T1 period and one during T2 period. Overall mortality rate: 0%. Conclusion - The esophageal endoscopic submucosal dissection could be performed effectively and safely by an adequately trained Western endoscopist.

Partially hydrolyzed guar gum increased colonic mucus layer in mice via succinate-mediated MUC2 production

Colonic mucus layers protect intestinal tissues against intestinal bacteria. We investigated the effects of dietary fiber and its metabolites on mucus production in the colonic mucosa. Mice were fed a partially hydrolyzed guar gum (PHGG)-containing diet and a fiber-free diet (FFD). The colon mucus layer, fecal short-chain fatty acid (SCFA) levels, and gut microbiota were evaluated. Mucin 2 (MUC2) expression was assessed in SCFA-treated LS174T cells. The role of AKT in MUC2 production was investigated. The mucus layer in the colonic epithelium was significantly increased in the PHGG group compared with that in the FFD group. In the PHGG group, an increase in Bacteroidetes in the stool was observed, and fecal acetate, butyrate, propionate, and succinate levels were significantly increased. However, MUC2 production was significantly increased only in succinate-stimulated LS174T cells. The succinate-induced MUC2 production was associated with AKT phosphorylation. Succinate mediated the PHGG-induced increase in the colon mucus layer.

Standard Endoscopic Mucosal Resection vs Precutting Endoscopic Mucosal Resection Using Novel Disk-Tip Snare for Colorectal Lesions

INTRODUCTION

SOUTEN (KANEKA Co., Tokyo, Japan) is a unique snare with a disk tip. We analyzed the efficacy of precutting endoscopic mucosal resection with SOUTEN (PEMR-S) for colorectal lesions.

METHODS

We retrospectively reviewed 57 lesions of 10-30 mm treated with PEMR-S at our institution from 2017 to 2022. The indications were lesions that were difficult for standard EMR due to size, morphology, and poor elevation by injection. Various therapeutic results of PEMR-S such as en bloc resection, procedure time, and perioperative hemorrhage were analyzed, and the results of 20 lesions of 20-30 mm with PEMR-S were compared to those of lesions with standard EMR (2012-2014) using propensity score matching. Additionally, the stability of the SOUTEN disk tip was analyzed in a laboratory experiment.

RESULTS

The polyp size was 16.5 ± 4.2 mm and the non-polypoid morphology rate was 80.7%. Histopathological diagnosis included 10 sessile-serrated lesions, 43 low-grade and high-grade dysplasias, and 4 T1 cancers. After matching, the en bloc resection and histopathological complete resection rates of lesions of 20-30 mm between PEMR-S and standard EMR (90.0% vs. 58.1%, p = 0.03 and 70.0% vs. 45.0%, p = 0.11). The procedure time (min) was 14.8 ± 9.7 and 9.7 ± 8.3 (p < 0.01). The en bloc resection (%) and procedure time of expert/non-expert were 89.7/85.7 (p = 0.96) and 6.1 ± 2.2/18.5 ± 7.2 (p < 0.01). The perioperative bleeding and hemostasis success rates with SOUTEN were 43.9% and 96.0%. In the experiment, the SOUTEN disk tip was fixed stably compared to other EMR snares.

CONCLUSIONS

PEMR-S achieved high en bloc resection of colorectal lesions of 20-30 mm though it leaded to long procedure time.

Evaluation of Environmental Stability and Disinfectant Effectiveness for Human Coronavirus OC43 on Human Skin Surface

The environmental stability of human coronavirus OC43 (HCoV-OC43) on the surface of human skin and the effectiveness of disinfectant against HCoV-OC43, which are important to prevent contact transmission, have not been clarified in previous studies. Using previously generated models, we evaluated HCoV-OC43 stability and disinfection effectiveness. Then we compared the results with those for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The median survival time of HCoV-OC43 on the surface of human skin was 24.6 h (95% confidence interval, 19.7 to 29.6 h), which was higher than that of SARS-CoV-2 (10.8 h). Although the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43 has a higher ethanol resistance than SARS-CoV-2, HCoV-OC43 on the skin surface was completely inactivated by a minimum of 50% ethanol within 5 s (the log reduction values were >4.0). Moreover, 1.0% chlorhexidine gluconate and 0.2% benzalkonium chloride showed relatively high disinfectant effectiveness, and the log reduction values when these disinfectants were applied for 15 s were >3.0. HCoV-OC43 is highly stable on the skin surface, which may increase the risk of contact transmission. Although HCoV-OC43 has relatively high ethanol resistance, appropriate hand hygiene practices with current alcohol-based disinfectants sufficiently reduce the risk of contact transmission. IMPORTANCE This study revealed the environmental stability of HCoV-OC43 and disinfectant effectiveness against HCoV-OC43, which had not been demonstrated in previous studies. HCoV-OC43 is highly stable on the surface of human skin, with a survival time of approximately 25 h. High stability of HCoV-OC43 may increase the risk of contact transmission. Furthermore, the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43, which is classified as an envelope virus, has a relatively high ethanol resistance. This finding suggests that disinfectant effectiveness may vary greatly depending on the virus and that each virus targeted for infection control should be evaluated individually. HCoV-OC43 on the skin surface was rapidly inactivated by 50% ethanol, which suggests that appropriate hand hygiene practices with current alcohol-based disinfectants can sufficiently reduce the risk of HCoV-OC43 contact transmission.

Obscure gastrointestinal bleeding from a large jejunal lipoma treated using an endoscopic unroofing technique with double balloon enteroscopy: a case study

Small intestinal lipomas are rare, but may cause obscure gastrointestinal bleeding. The endoscopic unroofing technique excises only the upper third of the lipoma and allows both histological confirmation and complete treatment with minimal risk of perforation. We present a rare case of obscure gastrointestinal bleeding caused by a jejunal lipoma. A 75-year-old man on antiplatelet therapy presented to our department with melena and anemia. Computed tomography revealed he had a 45-mm jejunal submucosal tumor with fat attenuation. Endoscopic resection using an endoscopic unroofing technique with double balloon enteroscopy was successfully performed. The tumor was confirmed to be a lipoma.

Randomized controlled trial comparing conventional and traction endoscopic submucosal dissection for early colon tumor (CONNECT-C trial)

OBJECTIVES

Endoscopic submucosal dissection (ESD) is a widely used treatment for early gastrointestinal cancer. However, colon ESD remains challenging. Previous studies on colon ESD using the traction method used a small sample, single-center design, providing insufficient evidence of this procedure's efficacy. We thus aimed to investigate the efficacy and safety of the traction method in colon ESD in this multicenter randomized trial.

METHODS

We conducted a prospective, multicenter, randomized, two-arm controlled trial at 10 facilities in Japan. A 1:1 allocation was conducted for the conventional ESD (C-ESD) and traction ESD (T-ESD) groups. The primary end-point was ESD procedure time.

RESULTS

We included 128 C-ESD and 123 T-ESD cases from April 2020 to August 2021. The median procedure times for C-ESD and T-ESD were 61 (40-100) and 53 (40-76) min (P = 0.18), respectively, and no significant differences were observed between the groups. Subgroup analysis showed that the median procedure times for patients with a lesion diameter of ≥30 mm in the C-ESD and T-ESD groups were 89 (57-80) and 69 (50-104) min (P = 0.05), respectively, and for nonexpert operators were 81 (62-120) and 64 (52-109) min (P = 0.07), respectively.

CONCLUSIONS

The traction method did not contribute to a significantly shortened ESD procedure time. However, this method may be useful when the tumor diameter is large or if the procedure is conducted by nonexpert endoscopists.

Analysis of Texture and Color Enhancement Imaging for Improving the Visibility of Non-polypoid Colorectal Lesions

INTRODUCTION

An endoscopic system using 5-color light-emitting diodes (LEDs) (EVIS X1; Olympus Co., Tokyo, Japan), which includes texture and color enhancement imaging (TXI), has been released. In this study, we analyzed the effects of TXI on the visibility of non-polypoid colorectal lesions and its diagnostic accuracy.

METHODS

We reviewed 101 non-polypoid lesions from 26 patients observed with white light imaging (WLI), narrow band imaging (NBI), and TXI. One representative image of each mode was evaluated by 6 endoscopists using a polyp visibility score of 4 (excellent) to 1 (poor). We calculated the color difference (CD) values for each lesion in the three modes. For tumor characteristics, one representative image of TXI and NBI magnification was evaluated by 3 experts according to a NBI classification.

RESULTS

The least squares means [95% confidence interval] of polyp visibility score of TXI (3.42 [3.06-3.77]) was significantly higher than that of WLI (2.85 [2.49-3.20], p < 0.001) but not that of NBI (3.33 [2.98-3.69], p = 0.258). The CD value of TXI (13.3 ± 6.3) was higher than that of WLI (9.7 ± 6.0, p < 0.001) but not that of NBI (13.1 ± 6.8, p = 0.81). For sessile serrated lesions, the CD value of TXI (11.1 ± 4.4) tended to be lower than that of NBI (12.6 ± 6.0, p = 0.07). The diagnostic accuracy and confidence level of magnification for NBI were significantly better than those for TXI (87.1 vs. 80.5%, p = 0.027, 87.5 vs. 62.7%, p < 0.001, respectively).

CONCLUSION

TXI showed better visibility than WLI in terms of the endoscopist's score and CD value and may improve polyp detection.

Aspirin-Mediated Prevention of Colorectal Adenomas Recurrence is Affected by Blood Biochemistry and Nutritional Intake

Aspirin has been shown to prevent the onset of colorectal adenoma and cancer. This study aimed to identify patient characteristics and blood chemistry factors related to the effect of aspirin. A total of 231 men and 59 women who participated in our previous randomized clinical study in 2007-2009 using aspirin or placebo (J-CAPP study) were analyzed. Interaction of aspirin with age at entry, body mass index (BMI), alcohol intake, blood biochemistry, and nutrients calculated from a semiquantitative food frequency questionnaire were analyzed on the basis of the presence of adenomas 2 years later. Our study showed that suppression of adenoma by aspirin was not affected by age or BMI. Among men, significant suppression of adenoma by aspirin was seen with triglyceride (TG) <167 mg/dL (P = 0.02), total cholesterol (T-cho) ≥220 mg/dL (P = 0.01), high-density lipoprotein (HDL) ≥60 mg/dL (P < 0.01), and low-density lipoprotein (LDL) ≥140 mg/dL (P = 0.01), aspartate aminotransferase (AST) <30 IU/L (P = 0.01), alanine aminotransferase <30 IU/L (P = 0.04), and gamma-glutamyl transpeptidase <60 IU/L (P = 0.04). In addition, the interaction was significant with TG ≥/<167 mg/dL (P = 0.02), T-cho ≥/<220 mg/dL (P = 0.03), HDL ≥/<60 mg/dL (P = 0.02), LDL ≥/<140 mg/dL (P = 0.03), and AST ≥/<30 IU/L (P = 0.01). Daily nutrient intake associated with aspirin was <2,000 mg sodium (P = 0.06) and ≥850 μg retinol equivalent (P = 0.05) among men, indicating a marginal effect on adenoma suppression. No significant differences were detected among women due to the small sample size. In conclusion, lipid metabolism and liver function were correlated with the suppressive effect of aspirin on the recurrence of colorectal adenoma.

PREVENTION RELEVANCE

Aspirin has been shown to prevent the onset of colorectal adenoma and cancer, and its effect modifications have been analyzed. Lipid metabolism and liver function were correlated with the suppressive effect of aspirin on the recurrence of colorectal adenoma.

Images of laser and light-emitting diode colonoscopy for comparing large colorectal lesion visibility with linked color imaging and white-light imaging

OBJECTIVES

In light-emitting diode (LED) and laser colonoscopy, linked color imaging (LCI) superiority to white-light imaging (WLI) for polyp detection is shown separately. We analyzed the noninferiority of LCI between LED and laser colonoscopy and that of WLI (LECOL study).

METHODS

We prospectively collected nonpolypoid lesions with WLI and LCI using LED and laser colonoscopy from January 2021 to August 2021. All images were evaluated randomly by 12 endoscopists (six nonexperts and six experts in three institutions) using the polyp visibility score: 4, excellent; 3, good; 2, fair; and 1, poor. The comparison score (LED better/similar/laser better) for redness and brightness was evaluated for WLI and LCI pictures of each lesion.

RESULTS

Finally, 63 nonpolypoid lesions were evaluated, and the mean polyp size was 24.5 ± 13.4 mm. Histopathology revealed 13 serrated lesions and 50 adenomatous/cancerous lesions. The mean polyp visibility scores of LCI pictures were significantly higher than those of WLI in the LED (3.35 ± 0.85 vs. 3.08 ± 0.91, P < 0.001) and the laser (3.40 ± 1.71 vs. 3.05 ± 0.97, P < 0.001) group, and the noninferiority of LCI pictures between LED and laser was significant (P < 0.001). The comparison scores revealed that the evaluation of redness and brightness (LED better/similar/laser better) were 26.8%/40.1%/33.1% and 43.5%/43.5%/13.0% for LCI pictures (P < 0.001) and 20.6%/44.3%/35.1% and 60.3%/31.7%/8.0% for WLI pictures (P < 0.001), respectively.

CONCLUSION

The noninferiority of polyp visibility with WLI and LCI in LED and laser colonoscopy was shown. WLI and LCI of LED tended to be brighter and less reddish than those of laser.

Retrospective investigation of mesalamine intolerance in patients with ulcerative colitis

Mesalamine is a key drug in the treatment of ulcerative colitis (UC) for both induction and maintenance therapy. On the other hand, it is known that there are some cases of mesalamine intolerance that are difficult to distinguish from symptoms due to aggravation of UC. The aim of this study is to investigate the clinical characteristic of mesalamine intolerance in UC. A retrospective, observational study was conducted. We enrolled 31 patients who were diagnosed as mesalamine intolerance between April 2015 to March 2020. We examined clinical features, time to onset, drug types of mesalamine, DLST positive rate, colonoscopy findings, disease activity, and clinical course after diagnosis. The average dose of mesalamine was 3.69 g and DLST-positive was 57.1%. Within the first 2 weeks from the start of mesalamine, 51.6% showed symptoms of intolerance. The serum CRP level was relatively high at ≥10.0 mg/dl in 53.6% of the cases. There was no difference in clinical background, symptoms, or laboratory findings between patients with DLST-positive and negative. In this study, we clarified the clinical characteristics of mesalamine intolerant patients, and found no difference in the clinical background or success rate of desensitization therapy between positive and negative DLST cases.

Association Between the Cool Temperature-dependent Suppression of Colonic Peristalsis and Transient Receptor Potential Melastatin 8 Activation in Both a Randomized Clinical Trial and an Animal Model

Background/Aims

Several studies have assessed the effect of cool temperature on colonic peristalsis. Transient receptor potential melastatin 8 (TRPM8) is a temperature-sensitive ion channel activated by mild cooling expressed in the colon. We examined the antispasmodic effect of cool temperature on colonic peristalsis in a prospective, randomized, single-blind trial and based on the video imaging and intraluminal pressure of the proximal colon in rats and TRPM8-deficient mice.

Methods

In the clinical trial, we randomly assigned a total of 94 patients scheduled to undergo colonoscopy to 2 groups: the mildly cool water (n = 47) and control (n = 47) groups. We used 20 mL of 15°C water for the mildly cool water. The primary outcome was the proportion of subjects with improved peristalsis after treatment. In the rodent proximal colon, we evaluated the intraluminal pressure and performed video imaging of the rodent proximal colon with cool water administration into the colonic lumen. Clinical trial registry website (Trial No. UMIN-CTR; UMIN000030725).

Results

In the randomized controlled trial, after treatment, the proportion of subjects with no peristalsis with cool water was significantly higher than that in the placebo group (44.7% vs 23.4%; P < 0.05). In the rodent colon model, cool temperature water was associated with a significant decrease in colonic peristalsis through its suppression of the ratio of peak frequency (P < 0.05). Cool temperature-treated TRPM8-deficient mice did not show a reduction in colonic peristalsis compared with wild-type mice.

Conclusion

For the first time, this study demonstrates that cool temperature-dependent suppression of colonic peristalsis may be associated with TRPM8 activation.

Investigation on the Inhibitory Effect of Wnt-5a on Colonic Mucosal Inflammation in Patients with Ulcerative Colitis

BACKGROUND

Recent progress in ulcerative colitis (UC) treatment has been remarkable, and various medications have been applied. However, some patients with UC are refractory to treatment and convert to surgery.

AIM

To investigate the role of colonic mucosal Wnt-5a expression in the pathogenesis of UC and the effect of bioactive Wnt-5a peptide on colitis in mice.

METHODS

Wnt-5a peptide was intraperitoneally administered to mice every day from the beginning of dextran sulfate sodium (DSS) treatment. The severity of colitis was evaluated based on body weight change, colonic length, and histological scores. Colonic mucosal TNF-α and KC mRNA expression levels were measured. This study included 70 patients with UC in clinical remission. Wnt-5a, TNFα, and IL-8 mRNA expression in the rectal mucosa were measured by quantitative real-time polymerase chain reaction using biopsy materials. Wnt-5a mRNA expression levels were compared between patients who relapsed and those in remission. We examined the correlation of Wnt-5a expression with TNF-α and IL-8 expression.

RESULTS

Wnt-5a peptide significantly attenuated the severity of DSS-induced colitis. Moreover, mucosal TNF-α and KC mRNA expression were significantly suppressed by Wnt-5a peptide treatment. Wnt-5a mRNA levels were significantly lower in patients with subsequent relapse than in those who remained in remission. Mucosal Wnt-5a was inversely correlated with TNF α and IL-8 expression.

CONCLUSION

Wnt-5a peptide suppressed colitis in mice, and decreased Wnt-5a expression was strongly associated with relapse in patients with UC. Wnt-5a may have an inhibitory effect on mucosal inflammation in UC, and Wnt-5a peptide could be a new therapeutic strategy.

Global Vertical Distribution of Water Vapor on Mars: Results From 3.5 Years of ExoMars-TGO/NOMAD Science Operations

We present water vapor vertical distributions on Mars retrieved from 3.5 years of solar occultation measurements by Nadir and Occultation for Mars Discovery onboard the ExoMars Trace Gas Orbiter, which reveal a strong contrast between aphelion and perihelion water climates. In equinox periods, most of water vapor is confined into the low-middle latitudes. In aphelion periods, water vapor sublimated from the northern polar cap is confined into very low altitudes-water vapor mixing ratios observed at the 0-5 km lower boundary of measurement decrease by an order of magnitude at the approximate altitudes of 15 and 30 km for the latitudes higher than 50°N and 30-50°N, respectively. The vertical confinement of water vapor at northern middle latitudes around aphelion is more pronounced in the morning terminators than evening, perhaps controlled by the diurnal cycle of cloud formation. Water vapor is also observed over the low latitude regions in the aphelion southern hemisphere (0-30°S) mostly below 10-20 km, which suggests north-south transport of water still occurs. In perihelion periods, water vapor sublimated from the southern polar cap directly reaches high altitudes (>80 km) over high southern latitudes, suggesting more effective transport by the meridional circulation without condensation. We show that heating during perihelion, sporadic global dust storms, and regional dust storms occurring annually around 330° of solar longitude (L _S) are the main events to supply water vapor to the upper atmosphere above 70 km.

Characteristics of colorectal neuroendocrine tumors in patients prospectively enrolled in a Japanese multicenter study: a first report from the C-NET STUDY

BACKGROUND

This is the first report from a multicenter prospective cohort study of colorectal neuroendocrine tumor (NET), the C-NET STUDY, conducted to assess the long-term outcomes of the enrolled patients. This report aimed to elucidate the clinicopathological features of the enrolled patients and lesions.

METHODS

Colorectal NET patients aged 20-74 years were consecutively enrolled and followed up at 50 institutions. The baseline characteristics and clinicopathological findings at enrollment and treatment were assessed.

RESULTS

A total of 495 patients with 500 colorectal NETs were included. The median patient age was 54 years, and 85.3% were asymptomatic. The most frequent lesion location was the lower rectum (88.0%); 99.4% of the lesions were clinically diagnosed to be devoid of metastatic findings, and 95.4% were treated with endoscopic resection. Lesions < 10 mm comprised 87.0% of the total, 96.6% had not invaded the muscularis propria, and 92.6% were classified as WHO NET grade 1. Positive lymphovascular involvement was found in 29.2% of the lesions. Its prevalence was high even in small NETs with immunohistochemical/special staining for pathological assessment (26.4% and 40.9% in lesions sized < 5 mm and 5-9 mm, respectively). Among 70 patients who underwent radical surgery primarily or secondarily, 18 showed positive lymph node metastasis.

CONCLUSIONS

The characteristics of real-world colorectal NET patients and lesions are elucidated. The high positivity of lymphovascular involvement in small NETs highlights the necessity of assessing the clinical significance of positive lymphovascular involvement based on long-term outcomes, which will be examined in later stages of the C-NET STUDY.

TRIAL REGISTRATION NUMBER

UMIN000025215.

Risk Factors of Delayed Bleeding After Cold Snare Polypectomy for Colorectal Polyps: A Multicenter Study

BACKGROUND

Delayed bleeding (DB) rarely occurs after cold snare polypectomy (CSP) for colorectal polyps, but no large-scale studies have investigated this. The present study evaluated the rate, characteristics, and risk factors of DB of CSP.

METHODS

We conducted a multicenter retrospective study at 10 Japanese institutions. A total of 18,007 patients underwent CSP for colorectal polyps ≤ 10 mm in size from March 2015 to September 2019, and cases of DB (DB group) were analyzed for the rate, antithrombotic drugs, polyp size, morphology, location, and risk factors. As a control, 269 non-bleeding cases (non-DB group) with 606 polyps who underwent CSP at the same 10 facilities in the 2-week study period were extracted.

RESULTS

We analyzed 26 DB cases with 28 lesions, and the total DB rate was 0.14% (26/18,007). The DB group had significantly higher rates of using antiplatelets (42.3% vs. 13.0%, p < 0.001) and anticoagulants (19.2% vs. 2.6%, p = 0.002), and significantly higher rates of polyp size ≥ 5 mm (67.9% vs. 45.2%, p = 0.015), rectal lesion (25.0% vs. 6.6%, p = 0.003), and polypoid lesion (89.3% vs. 55.3%, p < 0.001) than the non-DB group. A multivariate analysis (odds ratio; 95% confidence interval) for patient characteristics showed antiplatelet use (4.521; 1.817-11.249, p = 0.001) and anticoagulant use (7.866; 20.63-29.988, p = 0.003) as independent risk factors for DB. Polyp size ≥ 5 mm (3.251; 1.417-7.463, p = 0.005), rectal lesion (3.674; 1.426-9.465, p = 0.007), and polypoid lesion (7.087; 20.81-24.132, p = 0.002) were also risk factors for lesion characteristics.

CONCLUSIONS

The rate of DB was 0.14% and antithrombotic drug use, polyp size, location, and morphology were related to it.

Promotion Effects of Smoking in Polyp Development in Monozygotic Twins with Atypical Colorectal Polyposis

Smoking is a known risk factor for the development of colorectal polyps. Even in familial adenomatous polyposis and serrated polyposis syndrome, smoking is a risk factor of the development of polyps. Here, we report a case of monozygotic twins with atypical colorectal polyposis showing lots of hyperplastic polyps and adenomas and describe how the polyposis developed differently in the brothers based on the presence or absence of smoking. The case was of a set of monozygotic male twins, and the twins were in their 50s. The younger brother smoked 40 cigarettes a day since he was 16 years old. The older brother had smoked about 25 cigarettes a day since he was 16 years old but stopped smoking after he was diagnosed with polyposis. As we previously reported, we managed to remove polyps as much as possible from both twins without surgery. The median number of removed polyps (IQR: 25–75%) per colonoscopy for 20 years was 9.0 (3.5–14.8) in the older brother and 20.5 (7.5–35.5) in the younger brother. There was a significant difference between the twins (p < 0.01). Additionally, genetic tests found that the twins carried a rare missense variant of BRCA2, and this variation has not been previously reported. In conclusion, these monozygotic twins with atypical colorectal polyposis showing a new variant of BRCA2 suggest that smoking is related to the development of colorectal polyps. Further analysis will be required for the identified BRCA2 variant in possible involvement in the development of atypical polyposis.

Enhanced Visibility in Evaluating Gastric Cancer and Helicobacter pylori-Associated Gastritis Using Linked Color Imaging with a Light-Emitting Diode Light Source

BACKGROUND

In Japan, laser light source (Laser) endoscopy is widely available, and the characteristics of light-emitting diode light source (LED) endoscopy have not been clarified.

AIMS

We assessed the visibility of early gastric cancers (EGCs) and Helicobacter pylori (H. pylori)-associated gastritis for LED endoscopy compared with laser endoscopy using white-light imaging (WLI) and linked color imaging (LCI).

METHODS

We assessed 99 lesions between February 2019 and March 2020. The visibility was scored from four (excellent visibility) to one (poor visibility) by evaluating videos including EGCs and gastric mucosa captured using WLI and LCI with LED endoscopy (LED-WLI and LED-LCI, respectively) and laser endoscopy (Laser-WLI and Laser-LCI, respectively). The primary end point was the non-inferiority of the visibility of EGCs and H. pylori-associated gastritis between LED-/Laser-WLI and LED-/Laser-LCI.

RESULTS

The visibility scores of EGCs for LED-/Laser-WLI and LED-/Laser-LCI were 3.14/2.97 and 3.39/3.35, respectively. The visibility scores of H. pylori-associated gastritis [intestinal metaplasia (IM), diffuse redness (DR), regular arrangement of collecting venules (RAC) and map-like redness (MR)] for LED-/Laser-WLI and LED-/Laser-LCI were 3.05/2.85 and 3.60/3.50 (IM), 2.76/2.50 and 2.96/2.86 (DR), 2.69/2.44 and 2.77/2.62 (RAC) and 2.97/2.75 and 3.39/3.27 (MR). Non-inferiority was demonstrated for visualizing EGCs and H. pylori-associated gastritis.

CONCLUSIONS

LED-WLI and LED-LCI can be used to visualize EGCs and H. pylori-associated gastritis with non-inferiority to Laser-WLI and Laser-LCI. Furthermore, even with LED, LCI was more effective than WLI for evaluating EGCs and H. pylori-associated gastritis. Therefore, LED endoscopy can be used to detect EGCs and evaluate H. pylori-associated gastritis accurately.