Blood group O is a risk factor for delayed post-polypectomy bleeding.

BACKGROUND: Blood group O of ABO blood group system is considered as a risk factor for various bleeding events, but the relationship with endoscopic treatment-associated bleeding has yet to be investigated. This study aimed to evaluate whether blood group O is associated with delayed bleeding after colorectal endoscopic resection. METHODS: This was a retrospective observational study based on medical records at four university hospitals in Japan. We reviewed the records for consecutive patients who underwent colorectal endoscopic resection from January 2014 through December 2017. The primary outcome was the incidence of delayed bleeding, defined as hematochezia or melena, requiring endoscopy, transfusion, or any hemostatic intervention up to 28 days after endoscopic resection. Multivariate logistic regression analysis was performed to adjust the impact of blood group O on the delayed bleeding. RESULTS: Among 10,253 consecutive patients who underwent colorectal endoscopic resection during the study period, 8625 patients met the criteria. In total, delayed bleeding occurred in 255 patients (2.96%). The O group had significantly more bleeding events compared with the non-O group (A, B, and AB) (relative risk, 1.62 [95% confidence interval, 1.24-2.10]; P < 0.001). In multivariate logistic regression analysis, blood group O remained an independent risk factor for the bleeding (adjusted odds ratio, 1.60 [95% confidence interval, 1.18-2.17]; P = 0.002). CONCLUSIONS: Blood group O was associated with an increased risk of delayed bleeding in patients undergoing colorectal endoscopic resection. Preoperative screening for ABO blood group could improve risk assessments.

Real-time computer-aided diagnosis of diminutive rectosigmoid polyps using an auto-fluorescence imaging system and novel color intensity analysis software.

Objectives: An endoscopic technique that provides ≥90% negative predictive value (NPV) for differentiating neoplastic polyps is needed for the management of diminutive (≤5 mm) rectosigmoid polyps. This study aimed to assess whether a newly developed software can achieve ≥90% NPV for differentiating rectosigmoid diminutive polyps based on the green-to-red (G/R) ratio, obtained by dividing the green color tone intensity by the red color tone intensity on autofluorescence imaging (AFI). Methods: From December 2017 to May 2018, consecutive patients with known polyps who were scheduled for endoscopic treatment at our institution were prospectively recruited. All colorectal diminutive polyps were differentiated by computer-aided diagnosis using autofluorescence imaging (CAD-AFI) using a novel software-based automatic color intensity analysis; subsequent diagnosis was made by endoscopists based on trimodal imaging endoscopy (TME), which combines AFI, white-light imaging (WLI) and magnifying narrow-band imaging (M-NBI) findings. Thereafter, all polyps were removed endoscopically, and the histopathological diagnosis was evaluated. Results: Ninety-five patients with 258 diminutive rectosigmoid polyps and 171 diminutive non-rectosigmoid polyps were enrolled. Regarding diminutive rectosigmoid polyps, the NPV for differentiating neoplastic polyps was 93.4% (184/197) [95% confidence interval (CI), 89.0%-96.4%] with CAD-AFI and 94.9% (185/195) (95% CI, 90.8%-97.5%) with TME. The accuracy, sensitivity, specificity, and positive predictive value for differentiating diminutive rectosigmoid neoplastic polyps by CAD-AFI were 91.5%, 80.0%, 95.3% and 85.2%, respectively. Conclusions: Real-time CAD-AFI was effective for differentiating diminutive rectosigmoid polyps. This objective technology, which does not require extensive training or endoscopic expertise, can contribute to the effective management of diminutive rectosigmoid polyps.

Predicting outcomes in colorectal endoscopic submucosal dissection: a United States experience.

OBJECTIVE: Endoscopic submucosal dissection (ESD) allows for en bloc resection of superficial gastrointestinal neoplasms; however, US experience has been limited. We aimed to evaluate our clinical outcomes in colorectal ESD. DESIGN: This prospective study included consecutive patients undergoing colorectal ESD at a major US center. Demographics, lesion and technical characteristics, outcomes, adverse events, and pathological diagnoses were recorded. Factors affecting resection outcomes and procedure time were evaluated. RESULTS: 77 patients who underwent colorectal ESD were analyzed. Mean colorectal lesion diameter was 49.4 mm. Mean procedure time was 104.7 min, and 97.4% of patients were discharged home on the same day. En bloc, complete, and curative resection was achieved in 97.4%, 97.4%, and 93.5% of colorectal ESD cases. Microperforation and delayed bleeding rates were 1.3% and 3.9%. On univariable analysis, the presence of tattoo adversely affected en bloc resection (p = 0.002), complete resection (p = 0.002), and curative resection (p = 0.008). Prior EMR attempts adversely affected en bloc resection (p = 0.028), complete resection (p = 0.028), and procedure time (p = 0.008). On multivariable analysis, the presence of tattoo predicted failure to achieve curative resection (OR 0.13; 95% CI 0.02-0.98; p = 0.048). Lesion size > 50 mm (OR 3.89; 95% CI 1.13-13.41; p = 0.031), presence of tattoo (OR 9.38; 95% CI 1.05-83.83; p = 0.045), and prior EMR attempts (OR 7.13; 95% CI 1.76-28.90; p = 0.006) predicted procedure time ≥ 90 min. A scoring system was created to predict prolonged ESD procedure time and was externally validated, with AUC 0.78 (95% CI 0.73-0.83). CONCLUSION: This study demonstrates the effects of multiple risk factors on resection outcomes and procedure time in colorectal ESD. Tattoo placement and attempted EMR should be avoided for lesions being considered for ESD.

Simplified criteria for diagnosing superficial esophageal squamous neoplasms using Narrow Band Imaging magnifying endoscopy.

AIM: To simplify the diagnostic criteria for superficial esophageal squamous cell carcinoma (SESCC) on Narrow Band Imaging combined with magnifying endoscopy (NBI-ME). METHODS: This study was based on the post-hoc analysis of a randomized controlled trial. We performed NBI-ME for 147 patients with present or a history of squamous cell carcinoma in the head and neck, or esophagus between January 2009 and June 2011. Two expert endoscopists detected 89 lesions that were suspicious for SESCC lesions, which had been prospectively evaluated for the following 6 NBI-ME findings in real time: "intervascular background coloration"; "proliferation of intrapapillary capillary loops (IPCL)"; and "dilation", "tortuosity", "change in caliber", and "various shapes (VS)" of IPCLs (i.e., Inoue's tetrad criteria). The histologic examination of specimens was defined as the gold standard for diagnosis. A stepwise logistic regression analysis was used to identify candidates for the simplified criteria from among the 6 NBI-ME findings for diagnosing SESCCs. We evaluated diagnostic performance of the simplified criteria compared with that of Inoue's criteria. RESULTS: Fifty-four lesions (65%) were histologically diagnosed as SESCCs and the others as low-grade intraepithelial neoplasia or inflammation. In the univariate analysis, proliferation, tortuosity, change in caliber, and VS were significantly associated with SESCC (P < 0.01). The combination of VS and proliferation was statistically extracted from the 6 NBI-ME findings by using the stepwise logistic regression model. We defined the combination of VS and proliferation as simplified dyad criteria for SESCC. The areas under the curve of the simplified dyad criteria and Inoue's tetrad criteria were 0.70 and 0.73, respectively. No significant difference was shown between them. The sensitivity, specificity, and accuracy of diagnosis for SESCC were 77.8%, 57.1%, 69.7% and 51.9%, 80.0%, 62.9% for the simplified dyad criteria and Inoue's tetrad criteria, respectively. CONCLUSION: The combination of proliferation and VS may serve as simplified criteria for the diagnosis of SESCC using NBI-ME.

A feasibility study of chemically assisted endoscopic submucosal mechanical dissection using mesna for superficial esophageal squamous cell carcinomas.

BACKGROUND: Injection of mesna into submucosal layers was recently reported to chemically soften connective tissue and facilitate the gastric endoscopic submucosal dissection (ESD) procedure. This study aimed to evaluate the safety and feasibility of similarly using mesna for esophageal ESD (mesna ESD). METHODS: We performed mesna ESD in 20 consecutive patients with superficial esophageal squamous cell carcinomas (SESCCs). To do this, a submucosal fluid cushion was initially formed using sodium hyaluronate, and the esophageal lesion was circumferentially isolated with a short blade needle-knife. Mesna solution was then injected into the submucosal layer, which was dissected mechanically by cleavage using the tip of a cap-fitted endoscope. The number of electrosurgical incisions was recorded by computer software in real time. The data from 20 conventional ESD procedures without mesna (consecutive 10 SESCCs pre and post the 20 consecutive mesna ESD) were used for comparison to evaluate the mesna ESD. RESULTS: The mesna ESDs achieved en bloc and R0 resection success rates of 100 and 95 %, respectively. There was no perforation or uncontrollable hemorrhage during and after mesna ESD, and the median procedural time of submucosal dissection was significantly less with mesna ESD than with conventional ESD (median; 8 vs. 15 min, P < 0.05). There were also significantly fewer electrosurgical incisions made during the mesna ESD than with conventional ESDs (median; 65 vs. 183 times, P < 0.01). CONCLUSIONS: Mesna ESD for SESCCs is a safe procedure with the potential to facilitate esophageal ESD.

A double-blind, block-randomized, placebo-controlled trial to identify the chemical assistance effect of mesna submucosal injection for gastric endoscopic submucosal dissection.

BACKGROUND: Previous animal studies and a pilot clinical trial demonstrated that submucosal injection of a thiol compound called mesna could chemically soften connective tissues and thus facilitate endoscopic submucosal dissection (ESD). OBJECTIVE: To evaluate whether mesna injection could reduce procedural times for gastric ESD. DESIGN: Double-blind, block-randomized, controlled trial. SETTING: University hospital. PATIENTS: A total of 101 patients with superficial gastric cancer indicated for ESD were enrolled and randomly assigned to either the mesna or control (saline solution) group. INTERVENTION: Traditional ESD was performed with a single bolus injection of mesna or saline solution. MAIN OUTCOME MEASUREMENTS: Time for submucosal dissection (TSD). RESULTS: En bloc resection was achieved for all lesions in the mesna group (53/53) and 51 of 52 lesions (98.08%) in the control group. TSD was not statistically different between the groups (18.62 ± 13.9 [mean ± SD] minutes for the mesna group and 24.58 ± 24.55 [mean ± SD] minutes for the control group; P = .128), and there were fewer time-consuming cases (times over 30 minutes) in the mesna group compared with controls (7/53 vs 15/52; P = .049). Multivariate regression analysis demonstrated that use of mesna, specimen size, and the presence of fibrous scars were significantly correlated with TSD (P < .05). LIMITATIONS: Single-center study. CONCLUSION: TSD was not significantly different between the mesna and control injection groups, but multivariate analysis indicated that mesna injection reduced procedural challenges associated with the submucosal dissection. ( CLINICAL TRIAL REGISTRATION NUMBER: UMIN000003786.).

Visualization of colorectal neoplasia by a second-generation autofluorescence imaging system.

OBJECTIVE: Autofluorescence imaging (AFI) systems may allow better visualization of colorectal neoplasia than conventional methods. However, this is difficult to demonstrate objectively. Recently, a second-generation AFI system with a noise-reduction algorithm was developed. We aimed to objectively evaluate the visualization of colorectal neoplasia by using a second-generation AFI system and software to calculate the color-contrast index. MATERIAL AND METHODS: We retrospectively reviewed 53 consecutive colorectal neoplasias examined using the second-generation AFI system. Color-contrast indices between the colorectal lesions and the surrounding normal mucosa in the WLI, AFI and NBI images were calculated. The WLI, AFI, NBI and CE images were also evaluated by endoscopists using questionnaire-based visualization scores. RESULTS: The color-contrast index seen in the AFI images (33.74 ± 9.20) was significantly higher than that in either the WLI (11.14 ± 6.14) or NBI images (11.72 ± 7.12). There was no significant difference between the color-contrast indices of the WLI and NBI images. The mean AFI image visualization score (6.7 ± 1.8) was significantly higher than that of WLI (6.0 ± 1.7), and tended to be higher than that of the NBI images (6.1 ± 1.6) when assessed by less-experienced endoscopists. CONCLUSIONS: This study objectively demonstrates that compared to WLI and NBI, the second-generation AFI system enables superior visualization of colorectal neoplasms. The visualization scores were higher for the AFI images when evaluated by less-experienced endoscopists. These results indicate that the second-generation AFI system may aid less-experienced endoscopists in the detection of colorectal neoplasia.

Computer-aided diagnosis of neoplastic colorectal lesions using 'real-time' numerical color analysis during autofluorescence endoscopy.

OBJECTIVE: Differentiating non-neoplastic colorectal lesions from neoplastic lesions during screening colonoscopies is essential to reduce the unnecessary treatment of non-neoplastic lesions. The present study was conducted to verify the diagnostic yields of the computer-aided diagnostic system that enables 'real-time' color analysis of colorectal lesions when applied to autofluorescence endoscopy (AFE). PATIENTS AND METHODS: Consecutive patients who were scheduled to undergo a therapeutic colonoscopy in our department were enrolled in this study. The encountered lesions were evaluated in AFE and color-tone sampling was performed. Lesions with green/red (G/R) ratios less than 1.01 were judged to be neoplastic and those with G/R ratios of at least 1.01 were considered to be non-neoplastic. All lesions greater than 5 mm were endoscopically removed and lesions less than 5 mm were biopsied. RESULTS: During the study period, a total of 32 patients with 102 colorectal lesions were evaluated with AFE. The mean G/R ratio for all neoplastic lesions was 0.86 [95% confidence interval (CI), 0.63-1.01], which was significantly lower than the mean G/R ratio for non-neoplastic lesions (1.12; 95% CI, 0.98-1.26; P<0.001). The mean G/R ratios were 1.36 (95% CI, 1.21-1.57) in normal mucosa, 1.12 (95% CI, 0.98-1.26) in hyperplastic lesions, 0.88 (95% CI, 0.69-1.02) in adenomas, and 0.61 (95% CI, 0.54-0.73) in intramucosal cancers. A G/R ratio cutoff value of 1.01 was applied for discriminating between neoplastic lesions and non-neoplastic lesions, and yielded sensitivity, specificity, positive and negative predictive values of 94.2, 88.9, 95.6, and 85.2%, respectively. CONCLUSION: This diagnostic tool may lead to the reduction of unnecessary treatments for non-neoplastic lesions.

In vivo histologic imaging of the muscularis propria and myenteric neurons with probe-based confocal laser endomicroscopy in porcine models (with videos).

BACKGROUND: The submucosal tunneling technique enables us to endoscopically access deeper tissue layers. Use of probe-based confocal laser endomicroscopy (pCLE) provides optical histologic imaging on the site. OBJECTIVE: To determine the technical feasibility of ex vivo and in vivo pCLE imaging of the muscularis propria and myenteric neurons by using submucosal endoscopy with a mucosal flap safety valve (SEMF). DESIGN: Acute porcine model study. SETTING: Animal laboratory. INTERVENTION: Two ex vivo and 6 in vivo porcine models were used. A submucosal space was created with SEMF, and a neuronal molecular probe was topically applied onto the muscularis. Confocal imaging of the stained muscularis was performed by using pCLE. The selected sites were sampled, and the histopathology of the sites was analyzed. MAIN OUTCOME MEASUREMENTS: The two main outcome measures were the procedural success rate of submucosal access and the correlation between pCLE and histologic images. RESULTS: Submucosal access to the pCLE study site was successful in all attempts (100%; 17/17 sites). The muscularis propria was visualized with pCLE in the ex vivo and in vivo porcine models in 83.3% of sites (20/24), and the neuron-like cells were identified in 41.7% of sites (10/24). LIMITATIONS: Animal experiment. CONCLUSION: The muscularis propria and myenteric neurons could be selectively visualized with pCLE in vivo.

Ingesting 500 ml of polyethylene glycol solution during capsule endoscopy improves the image quality and completion rate to the cecum.

The benefits of bowel preparation prior to capsule endoscopy (CE) are controversial. The aim of this study was to examine whether ingesting a small amount of polyethylene glycol (PEG) during, not before, the CE procedure improves the image quality and the cecal completion rate. A prospective single-blind controlled study was conducted including 59 patients. The initial 32 patients (group A) received no preparation, and the subsequent 27 patients (group B) ingested 500 ml of PEG starting 30 min after swallowing the capsule. The capsule reached the cecum in 65.6% of the patients in group A and 88.9% of the patients in group B (P = 0.038). The use of PEG during CE examination significantly improved the image quality, and this effect was more pronounced in the distal ileum. Ingesting a small amount of PEG during CE examination significantly improves both the CE image quality and the cecal completion rate.