Endoscopic mucosal resection

Efficacy and Safety of Cold Versus Hot Snare Endoscopic Mucosal Resection in Colorectal Polyp Removal: A Systematic Review and Meta-Analysis

BACKGROUND

Cold snare endoscopic mucosal resection (C-EMR) is hypothesized to offer a safety advantage over hot snare endoscopic mucosal resection (H-EMR). The primary objective of this meta-analysis is to evaluate the effectiveness and safety of C-EMR versus H-EMR for the management of colorectal lesions.

METHODS

A meta-analysis was performed to determine pooled odds ratios (ORs) for comparing outcomes between the C-EMR and H-EMR groups.

RESULTS

The pooled OR for complete resection rates were estimated at 0.70 (95% CI: 0.36-1.36, P =0.29) and en bloc rates were 0.24 (95% CI: 0.05-1.08, P=0.06) between C-EMR group and H-EMR group. The overall complete resection rate for C-EMR was 84%, and the en bloc resection rate was 57. Notably, C-EMR was associated with a significantly lower incidence of delayed bleeding. The recurrence rate of polyps was very low (2%) when treating sessile serrated polyp (SSP) lesions, but higher (23%) for non-SSP lesions. Subgroup analysis revealed minimal recurrence of polyps after using C-EMR for lesions between 10 to 20 mm and ≥20 mm.

CONCLUSIONS

This meta-analysis suggests that C-EMR could be a safer and equally effective alternative to H-EMR for resecting colorectal lesions. We recommend C-EMR as the preferred method for excising large colorectal lesions.

The role of cap-assisted endoscopy and its future implications

Cap-assisted endoscopy refers to a procedure in which a short tube made of a polymer (mostly transparent) is attached to the distal tip of the endoscope to enhance its diagnostic and therapeutic capabilities. It is reported to be particularly useful in: (1) minimizing blind spots during screening colonoscopy, (2) providing a constant distance from a lesion for clear visualization during magnifying endoscopy, (3) accurately assessing the size of various gastrointestinal lesions, (4) preventing mucosal injury during foreign body removal, (5) securing adequate workspace in the submucosal space during endoscopic submucosal dissection or third space endoscopy, (6) providing an optimal approach angle to a target, and (7) suctioning mucosal and submucosal tissue with negative pressure for resection or approximation. Here, we review various applications of attachable caps in diagnostic and therapeutic endoscopy and their future implications.

Structural insights into the potential binding sites of Cathepsin D using molecular modelling techniques

Alzheimer's disease (AD) is the most prevalent type of dementia caused by the accumulation of amyloid beta (Aβ) peptides. The extracellular deposition of Aβ peptides in human AD brain causes neuronal death. Therefore, it has been found that Aβ peptide degradation is a possible therapeutic target for AD. CathD has been known to breakdown amyloid beta peptides. However, the structural role of CathD is not yet clear. Hence, for the purpose of gaining a deeper comprehension of the structure of CathD, the present computational investigation was performed using virtual screening technique to predict CathD's active site residues and substrate binding mode. Ligand-based virtual screening was implemented on small molecules from ZINC database against crystal structure of CathD. Further, molecular docking was utilised to investigate the binding mechanism of CathD with substrates and virtually screened inhibitors. Localised compounds obtained through screening performed by PyRx and AutoDock 4.2 with CathD receptor and the compounds having highest binding affinities were picked as; ZINC00601317, ZINC04214975 and ZINCC12500925 as our top choices. The hydrophobic residues Viz. Gly35, Val31, Thr34, Gly128, Ile124 and Ala13 help stabilising the CathD-ligand complexes, which in turn emphasises substrate and inhibitor selectivity. Further, MM-GBSA approach has been used to calculate binding free energy between CathD and selected compounds. Therefore, it would be beneficial to understand the active site pocket of CathD with the assistance of these discoveries. Thus, the present study would be helpful to identify active site pocket of CathD, which could be beneficial to develop novel therapeutic strategies for the AD.

Effect of endoscopic mucosal resection and endoscopic submucosal dissection on postoperative wound complications in patients with gastric cancer: A meta-analysis

Endoscopic submucosa dissection (ESD) allows complete excision of the whole lesion, which results in a higher percentage of complete excision and an improved quality of life by minimizing the amount of excision as opposed to an endoscopic mucosal resection (EMR). Although ESD is now being carried out in the majority of hospitals, ESD's possible complications (such as trauma and perforation) have given rise to doubts about ESD practices in patients with early-stage stomach cancer when deciding on therapy and reimbursement. This study was designed to evaluate the effectiveness and safety of ESD over EMR in treating early-stage stomach cancer. Four main databases have been searched, including EMBASE and published. The ROBINS-I tool suggested in the Cochrane Handbook has been applied to evaluate the quality of the chosen trials. It may better reflect the risk of bias in the included studies. The meta-analyses were carried out with ReMan 5.3, and the results were treated with endote. Seven cohort studies have been completed. Meta analysis indicated that EMR and ESD surgery did not differ significantly from each other in terms of postoperative haemorrhage (OR, 0.76; 95%CI, 0.56,1.04 p = 0.09); EMR, however, was associated with a lower rate of postoperative perforation than ESD surgery (OR, 0.36; 95%CI, 0.24,0.54 p < 0.0001). Taking into account that ESD and EMR did not differ significantly in the risk of wound bleeding, even though the risk of perforation is not likely to result in life-threatening illness. In the analysis of these data, however, the potential advantages of EMR might be greater than ESD.

Safety and Efficacy of Powered Non-Thermal Endoscopic Resection Device for Removal of Colonic Polyps: A Systematic Review and Meta-Analysis

Background

Endoscopic mucosal resection is a frequently employed method for removing colonic polyps. Nonetheless, the recurrence of these polyps over a healed submucosal base can complicate the extraction of leftover lesions through standard procedures. EndoRotor®, a non-thermal device specifically designed for endoscopic mucosal resection, has recently been assessed for its utility in removing colonic polyps, non-dysplastic Barrett's esophagus, and pancreatic necrosis. We conducted a systematic review and meta-analysis to ascertain the safety and efficacy of EndoRotor® in resecting scared or recurrence colonic polyps.

Methods

We conducted an exhaustive review of existing literature using databases such as Medline, Embase, Web of Science, and the Cochrane Library until January 2023. Our aim was to find all studies that assessed the safety of non-thermal endoscopic resection devices in removing colonic polyps. The primary outcome we focused on was the rate of technical success. Secondary outcomes that we considered included the frequency of remaining lesions and instances of adverse events. To analyze these data, we used comprehensive meta-analysis software.

Results

Our analysis incorporated three studies comprising 54 patients who underwent resection of 60 lesions. The combined technical success rate was 93.9% (95% confidence interval (CI): 77.7-98.6%, I2 = 25.5%). In patients who had another endoscopic examination, 20 were found to have a residual lesion. After the initial session, the combined rate of remaining lesions was 39.8% (95% CI: 15.3-70.8%, I2 = 74.5%). There were eight occurrences of intraoperative bleeding and four instances of bleeding post-procedure. The combined rate of intraoperative bleeding was 13.2% (95% CI: 6.7-24.3%, I2 = 0%), and post-procedure bleeding stood at 8.5% (95% CI: 3.4-19.8%, I2 = 0%). Only one major bleeding event was recorded, and no cases of perforation were reported.

Conclusion

Our research indicates that the EndoRotor® effectively removes scarred colonic polyps, though the rate of remaining lesions is significant, potentially necessitating several sessions for a thorough removal. There is a need for broader prospective studies, mainly randomized controlled trials, to further assess EndoRotor®'s efficiency and safety in eliminating colonic polyps.

Unlocking quality in endoscopic mucosal resection

A review of the development of the key performance metrics of endoscopic mucosal resection (EMR), learning from the experience of the establishment of widespread colonoscopy quality measurements. Potential future performance markers for both colonoscopy and EMR are also evaluated to ensure continued high quality performance is maintained with a focus service framework and predictors of patient outcome.

Research trends on endoscopic mucosal resection: A bibliometric analysis from 1991 to 2021

Background

In recent years, the rapid development of digestive endoscopy technology has brought revolutionary changes to endoscopic therapy. A growing number of articles have been published annually. We aimed to explore global scientific outputs and hotspots of endoscopic mucosal resection (EMR) published by different countries, organizations, and authors.

Methods

We extracted relevant publications from the Web of Science Core Collection (WOSCC) on June 23, 2022. We examined the retrieved data by bibliometric analysis (e.g., cocited and cluster analysis, keyword co-occurrence) using the software CiteSpace and VOSviewer to analyze and predict the trends and hot spots in this field.

Results

A total of 2,695 papers were finally identified. The results showed that the number of articles fluctuated with the year and reached its peak in 2021. NATIONAL CANCER CENTER JAPAN was the most influential institution. MICHAEL J BOURKE and YUTAKA SAITO are two of the most prolific scholars. ENDOSCOPY and GASTROINTESTINAL ENDOSCOPY were the most productive journals. “Early gastric cancer” and “Barrett's esophagus” were the focus of EMR research. “Adverse events”, “cold snare polypectomy” and “outcomes” have become increasingly popular in recent years and could become hot spots in the future.

Conclusion

In this study, we summarized the characteristics of the publications; identified the most influential countries, institutions, and journals; and identified the leading topics in the EMR field.

Potential of temperature-response collagen-genipin sol as a novel submucosal injection agent for endoscopic resection: Acute and chronic phase study using living animals

OBJECTIVES

We proposed a novel temperature-response collagen sol as a submucosal injection agent for endoscopic resection (ER) using pepsin-solubilized collagen (PSC) and genipin (Ge) in a prior study. This study aimed to evaluate the usefulness and safety of the sol (PSC/Ge) in acute and chronic phase experiments using living animals.

METHODS

In experiment 1, we performed endoscopic submucosal dissection (ESD) for six pigs using normal saline (NS), sodium hyaluronate (SH), and PSC/Ge. We compared the required amount of each agent per unit area and procedure time. In experiment 2, we created artificial ulcers with endoscopic mucosal resection (EMR) for five pigs using NS and PSC sol. We compared the artificial ulcer residual rate at 7 and 14 days after EMR, and the scarring rate at 14 days after EMR.

RESULTS

The required amount of agents per unit area for PSC/Ge (0.8 ± 0.8 mL/cm² ) and SH (1.1 ± 0.8 mL/cm² ) were significantly smaller than that for NS (1.8 ± 0.7 mL/cm² ). The total procedure time did not have a statistical difference. The artificial ulcer residual rates were 47.3 ± 0.7% for NS and 40.3 ± 0.7% for PSC/Ge on day 7 (P = 0.51), and 15.0 ± 0.1% for NS and 10.2 ± 0.1% for PSC/Ge sol on day 14 (P = 0.35). The scarring rate on day 14 was 10% for NS and 20% for PSC/Ge.

CONCLUSION

We demonstrated the feasibility of a novel temperature-response collagen gel as a submucosal injection agent for ER in the acute and chronic phase animal experiment.

From advanced diagnosis to advanced resection in early neoplastic colorectal lesions: Never-ending and trending topics in the 2020s

Colonoscopy represents the most widespread and effective tool for the prevention and treatment of early stage preneoplastic and neoplastic lesions in the panorama of cancer screening. In the world there are different approaches to the topic of colorectal cancer prevention and screening: different starting ages (45-50 years); different initial screening tools such as fecal occult blood with immunohistochemical or immune-enzymatic tests; recto-sigmoidoscopy; and colonoscopy. The key aspects of this scenario are composed of a proper bowel preparation that ensures a valid diagnostic examination, experienced endoscopist in detection of preneoplastic and early neoplastic lesions and open-minded to upcoming artificial intelligence-aided examination, knowledge in the field of resection of these lesions (from cold-snaring, through endoscopic mucosal resection and endoscopic submucosal dissection, up to advanced tools), and management of complications.

Endoscopic Resection Versus Surgery in the Treatment of Early Gastric Cancer: A Systematic Review and Meta-Analysis

Background and Aim

Endoscopic resection (ER) is the preferred approach to treat early gastric cancer (EGC) in patients without suspected lymph node involvement and that meet the criteria for ER. Surgery is a more aggressive treatment, but it may be associated with less recurrence and the need for reintervention. Previous meta-analyses comparing ER with surgery for EGC did not incorporate the most recent studies, making accurate conclusions not possible.

Methods

This systematic review and meta-analysis aimed to examine complete resection, length of hospital stay (LOHS), adverse events (AEs), serious AEs, recurrence, 5-year overall survival (OS), and 5-year cancer-specific survival (CSS) in patients with EGC.

Results

A total of 29 cohorts studies involving 20559 patients were included. The ER (n = 7709) group was associated with a lower incidence of AEs (RD = -0.07, 95%CI = -0.1, -0.04, p < 0.0001) and shorter LOHS (95% CI -5.89, -5.32; p < 0,00001) compared to surgery (n = 12850). However, ER was associated with lower complete resection rates (RD = -0.1, 95%CI = -0.15, -0.06; p < 0.00001) and higher rates of recurrence (RD = 0.07, 95%CI = 0.06; p < 0.00001). There were no significant differences between surgery and ER in 5-year OS (RD = -0.01, 95%CI = -0.04, 0.02; p = 0.38), 5-year CSS (RD = 0.01, 95%CI = 0.00, 0.02; p < 0.17), and incidence of serious AEs (RD = -0.03, 95%CI = -0.08, 0.01; p = 0.13).

Conclusions

ER and surgery are safe and effective treatments for EGC. ER provides lower rates of AEs and shorter LOHS compared to surgery. Although ER is associated with lower complete resection rates and a higher risk of recurrence, the OS and CSS were similar between both approaches.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021255328.

Potential Factors Predicting Histopathologically Upgrade Discrepancies between Endoscopic Forceps Biopsy of the Colorectal Low-Grade Intraepithelial Neoplasia and Endoscopic Resection Specimens

Background

It was gradually accepted that endoscopic fragment biopsy (EFB) diagnosis cannot accurately guarantee the absence of higher-grade neoplasms within the lesion of the digestive tract. There are no well-established predictors for histopathologically upgrade discrepancies between EFB diagnosing colorectal low-grade intraepithelial neoplasia (LGIN) and endoscopic resection (ER) specimens.

Methods

A total of 918 colorectal LGINs was histopathologically diagnosed by EFB, including 162 cases with upgrade discrepancy and 756 concordant cases. We compared clinicopathological data of EFB and ER specimens between these two groups. Multivariate analysis was performed to identify predictors for this upgrade histopathology.

Results

The predominant upgrade discrepancy of LGINs diagnosed by EFB was upgrades to high-grade dysplasia (114/918, 12.4%), followed by upgrades to intramucosal carcinoma (33/918, 3.6%), submucosal adenocarcinoma (10/918, 1.1%), and advanced adenocarcinoma (5/918, 0.5%). NSAID history (OR 4.83; 95% CI, 2.27-10.27; p < 0.001), insufficient EFB number (OR 2.99; 95% CI, 1.91-4.68; p < 0.001), maximum diameter ≥ 1.0 cm (OR 6.18; 95% CI, 1.32-28.99; p = 0.021), lobulated shape (OR 2.68; 95% CI, 1.65-4.36; p < 0.001), erythema (OR 2.42; 95% CI, 1.50-3.91; p < 0.001), erosion (OR 7.12; 95% CI, 3.91-12.94; p < 0.001), surface unevenness (OR 2.31; 95% CI, 1.33-4.01; p = 0.003), and distal location of the target adenoma (OR 3.29; 95% CI, 1.68-6.41; p < 0.001) were associated with the histologically upgrade discrepancies.

Conclusion

NSAID history, insufficient EFB number, adenoma size and location, and abnormal macroscopic patterns are potential predictors for upgrade histopathology of LGINs diagnosed by EFBs. The standardization of EFB number and advanced imaging techniques could minimize the risk of neglecting the potential of this upgrade histopathology.

Comparison of endoscopic treatments for small gastric adenomas

BACKGROUND

Gastric adenomas can be successfully treated with endoscopic resection, including endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR). The aim of this study was to evaluate and compare the efficacy of ESD and EMR with circumferential precutting (EMR-P) in the treatment of small gastric adenomas.

METHODS

This study included 1014 gastric adenomas ≤ 15 mm in diameter treated with ESD or EMR-P from 2012 to 2019, retrospectively. Propensity score matching between the ESD and EMR-P groups (1:1 to 3:1) was performed according to age, sex, tumor size, tumor location (upper, middle, and lower thirds), morphology, and preprocedural histology. The procedure time and the rates of en bloc resection, complete resection, adverse events, and local recurrence were compared between the two groups.

RESULTS

After propensity score matching, 478 lesions (ESD: 295, EMR-P: 183) were analyzed. The rates of en bloc resection (94.9% vs. 93.4%, p = 0.498), complete resection (93.6% vs. 90.2%, p = 0.177), bleeding (8.1% vs. 3.8%, p = 0.063), and local recurrence (0.0% vs. 1.4%, p = 0.185) did not significantly differ between the two groups. The procedure time was significantly longer for ESD than for EMR-P (p < 0.001). In the EMR-P group, the complete resection rate was significantly lower in the upper third than in the middle and lower thirds (p < 0.001).

CONCLUSION

EMR-P is as effective as ESD for the treatment of small gastric adenomas. However, the efficacy of EMR-P is lower for gastric adenomas in the proximal stomach.

Self-completion method of endoscopic submucosal dissection using the Endosaber for treating colorectal neoplasms (with video)

Endoscopic submucosal dissection (ESD) is effective for the treatment of colorectal neoplasms. We have developed a self-completion ESD (S-ESD) using Endosaber without requiring additional instruments or assistance. This prospective cohort study was conducted to investigate the feasibility of S-ESD for colorectal neoplasms. Patients with colorectal neoplasms measuring 20–40 mm in size were enrolled. A single operator, without assistance, performed ESD using only the Endosaber. The primary outcome was the success rate of S-ESD. Secondary outcomes included procedure time, the rates of en bloc, complete, and curative resection, and complication rates, including the incidence of perforation and delayed bleeding. In total, 15 patients with 15 lesions were enrolled. The median size of the resected lesions was 28 mm (interquartile range 25–29 mm). S-ESD success rate of 100% was achieved. The median procedure time was 44 min (29.5–53.5 min). We observed en bloc, complete, and curative resection rates of 100%, 93.3%, and 86.7%, respectively, and a complication rate of 6.7% (perforation: 0%, delayed bleeding: 6.7%). S-ESD for colorectal neoplasms was successfully performed with favorable treatment outcomes and low complication rates. S-ESD reduces the number of devices and extent of assistance, making S-ESD a simple and cost-effective procedure.

Polypectomy for Large Polyps with Endoscopic Mucosal Resection

Beginning in 1955, when the saline injection was first described to prevent transmural injury during polyp fulguration, endoscopic mucosal resection (EMR) has grown exponentially, both in scope and in practice. Because EMR is an organ-preserving technique even for large polyps, this allows for comparable outcomes to surgery, but substantially improved cost savings and significantly reduced morbidity and mortality. To achieve this, however, one must master the 4 fundamental components that are critical to the success of EMR- time, team, tools, and technique. This article aims to provide a compendium of state of the art updates within the field of endoluminal resection.

Long-term clinical outcomes of patients diagnosed with pT1a-muscularis mucosae with lymphovascular invasion or pT1b after endoscopic resection for cT1N0M0 esophageal squamous cell carcinoma

BACKGROUND

Endoscopic resection (ER) is performed for early esophageal squamous cell carcinoma (ESCC) cases. Additional esophagectomy or chemoradiotherapy is recommended for non-curative resection (NCR) even with pathologically negative vertical margins (pVM0); however, their clinical outcomes remain unknown. We examined the long-term clinical outcomes of NCR for ESCCs according to additional treatments.

METHODS

We retrospectively analyzed the data of patients who underwent ER for cT1N0M0 ESCC between 2009 and 2017 judged to have NCR, which defined when pathologically diagnosed as invading the submucosa (SM) or muscularis mucosae (MM) involving lymphovascular invasion (LVI), pVM0, and endoscopically judged as negative horizontal margin. Additional esophagectomy (involving three-field lymphadenectomy), chemoradiotherapy [mainly cisplatin and 5-fluorouracil with concurrent radiotherapy (41.4 Gy)], or observation was undertaken. Thereafter, computed tomography was performed every 6-12 months. The cumulative recurrence (CRR) and recurrence-free survival (RFS) rates were evaluated.

RESULTS

Eighty-nine patients were included. Among them, 14 had pathologically diagnosed pMM with LVI; 9 and 6, and 32 and 28 patients had pSM1 and pSM2 without and with LVI. Twenty-one patients underwent observation, whereas 18 and 50 underwent esophagectomy and chemoradiotherapy. During the 60.6-month median follow-up period, nine patients had recurrence; among them, six patients had occurrence at > 4 years after ER. The 5-year CRR/RFS rates were 35.7%/48.1%, 13.4%/80.4%, and 0.0%/98.0% in the observation, esophagectomy, and chemoradiotherapy groups, respectively (observation vs. chemoradiotherapy; P < 0.001).

CONCLUSIONS

Additional treatments showed better long-term outcomes than observation for patients with NCR. As recurrence may occur at > 4 years after ER, careful long-term follow-up examinations are needed.

Closure of gastric perforations during endoluminal resection using a novel biodegradable collagen sol: A feasibility survival study on porcine model (with video)

OBJECTIVE

A prior study using porcine colon demonstrated the feasibility of a novel injectable, temperature?responsive, and biodegradable collagen sol (ICS) that transforms from a liquid to a gel state in response to body temperature for endoscopic closure of perforation during endoscopic resection (ER). This study aims to report the acute and survival outcomes of ICS for gastric perforations during ER.

METHODS

In two experiments using nine live pigs under general anesthesia, four and six perforations (3-5\xA0mm) were created using an electrosurgical knife in acute and survival experiments, respectively. ICS was delivered to the perforations using an endoscopic catheter. In Experiment 1, a leak test and histopathology were performed on all explanted stomachs after euthanization. In Experiment 2, perforation sites were assessed by gastroscopy and histopathology 7, 14 and 28\xA0days post?

RESULTS

In Experiment 1, gastroscopy confirmed complete closure of the perforations with ICS and no evidence of leak. Subsequent histopathology revealed a fixation of collagen gel (CG) as a sealant agent at the perforation sites. There were no adverse effects related with ESD or the use of ICS. In Experiment 2, histopathology revealed a fixation of CG as a sealant agent, replacement with granulation tissue and no CG; and fibrotic tissue at 7, 14 and 28\xA0days, respectively.

CONCLUSIONS

This study presents a novel method using ICS, demonstrating promising efficacy and safety profile for endoscopic closure of perforations during ER. Further studies are necessary before translating to clinical use.

Advances in gastrointestinal surgical endoscopy

Surgeons have a role in observing, detect abnormalities, disease, and other deficiencies in function which could be treated. Diagnosing and treating back days were challenging for many reasons. However, technology's innovation enhances surgeons' ability to treat their patients. The term endoscopy refers to the Greek prefix endo- ("within") and the verb skopein ("to view or observe"). Endoscopy is practical both in the diagnosis and treatment of various pathologies. Technological advances, especially in endoscopy, gradually progress and discover many possibilities which allow rapid advancement. Endoscopy development aims to assess human orifice that has not been inspected, probed, and examined over the centuries. Endoscopy over these decades is improving, which led to new problem solving using advanced technological approaches. Thus, a surgeon can solve any issues from examination, diagnosis, and treatment using progressive endoscopy evolution. This review delivers a brief history of advances in surgical endoscopy and describes current endoscopy development.

Current Endoscopic Resection Techniques for Gastrointestinal Lesions: Endoscopic Mucosal Resection, Submucosal Dissection, and Full-Thickness Resection

Background

Endoscopic resection of dysplastic lesions in early stages of cancer reduces mortality rates and is recommended by many national guidelines throughout the world. Snare polypectomy and endoscopic mucosal resection (EMR) are established techniques of polyp removal. The advantages of these methods are their relatively short procedure times and acceptable complication rates. The latter include delayed bleeding in 0.9% and a perforation risk of 0.4-1.3%, depending on the size and location of the resected lesion. EMR is a recent modification of endoscopic resection. A limited number of studies suggest that larger lesions can be removed en bloc with low complication rates and short procedure times. Novel techniques such as endoscopic submucosal dissection (ESD) are used to enhance en bloc resection rates for larger, flat, or sessile lesions. Endoscopic full-thickness resection (EFTR) is employed for non-lifting lesions or those not easily amenable to resection. Procedures such as ESD or EFTR are emerging standards for lesions inaccessible to EMR techniques.

Summary

Endoscopic treatment is now regarded as first-line therapy for benign lesions.

Key Message

Endoscopic resection of dysplastic lesions or early stages of cancer is recommended. A plethora of different techniques can be used dependent on the lesions.

Evolving management of colorectal polyps

Advances in endoscopic technology have led to increased success in colorectal cancer (CRC) screening and polyp management, with reduction of CRC incidence and mortality. Despite these advances, CRC is still one of the leading causes of cancer deaths, and half of all CRC develops from lesions that were missed during colonoscopy while one-fifth of CRC arise from prior incomplete resection. Techniques to improve polyp detection are needed, along with optimization of complete resection of any abnormal lesions that are found. This article will review the currently available endoscopic resection techniques and will discuss where they fit in the management of polyps of different sizes and types, such as pedunculated versus nonpedunculated, and those with or without suspected invasion.

[Pneumothorax Following Gastric Endoscopic Mucosal Resection]

An endoscopic mucosal resection (EMR) is used widely as an alternative treatment to a surgical resection for early gastric neoplastic lesions. Among the unusual complications of gastric EMR, perforation is usually manifested as a pneumoperitoneum. This paper reports a patient with a left-side pneumothorax without pneumoperitoneum as a complication of gastric EMR. The patient developed a left side pneumothorax after gastric EMR in the gastric fundus and recovered without further complications after conservative treatment, including endoscopic clipping.

Serrated polyps of the colon and rectum: a concise review

"Serrated polyps" is the term used for epithelial lesions of the colon and rectum that have a "sawtooth" pattern on the polyp's surface and crypt epithelium. The so-called serrated pathway describes the progression of sessile serrated adenomas and traditional serrated adenomas to colorectal cancer. Said pathway is well recognized as an alternative mechanism of carcinogenesis and accounts for 15-30% of the cases of colorectal cancer. It also explains a large number of the cases of interval colorectal cancer. Thus, due to their usually aggressive and uncertain behavior, serrated polyps are of the utmost importance in colorectal cancer screening. Our aim was to review the history, current nomenclature, pathophysiology, morphology, treatment, and surveillance of serrated polyps.

Novel temperature-responsive, biodegradable and injectable collagen sol for the endoscopic closure of colonic perforation holes: Animal study (with videos)

OBJECTIVES

Endoscopic submucosal dissection (ESD) poses a risk of intraprocedural perforation. We have developed a biodegradable injectable collagen sol that undergoes a liquid-to-gel formation in response to body temperature. Here, we investigated the feasibility of this novel collagen sol for the endoscopic closure of iatrogenic perforation holes.

METHODS

In two experiments, 12 and 5 colonic perforation holes (3-5 mm) were made using an ESD knife in four and three live pigs under general anesthesia, respectively. In Experiment 1, collagen sol was delivered to the perforation holes using an endoscopic catheter. When the colon was expanded by CO₂ insufflation, endo-clips were applied to the perforation holes. For Experiment 2, Collagen sol adjusted based on the Experiment 1 results was delivered to the perforation holes in the same manner. A leak test was performed for every colon after the pigs were killed, and the histology of the perforation sites was evaluated.

RESULTS

In both experiments, collagen sol was smoothly delivered to the target area and fixed as a gel on the perforation holes. Experiment 1, 83% (10/12) of the perforation holes were completely closed, and all endo-clips were placed with composure. Experiment 2, all perforation holes were completely closed with collagen gel. There was no leak from the perforation holes. Histology revealed a fixation of the collagen gel as an embolus agent in the perforation holes.

CONCLUSIONS

This novel collagen sol may be used for the endoscopic closure of intraprocedural perforation. Further studies will determine this collagen sol's clinical feasibility and safety.

Colorectal EMR outcomes in octogenarians versus younger patients referred for removal of large (≥20 mm) nonpedunculated polyps

BACKGROUND AND AIMS

Data are limited on safety and outcomes of colorectal EMR in octogenarians (≥80 years old). We sought to review outcome data for patients aged ≥80 in a prospectively collected database of patients referred for large polyp removal.

METHODS

We retrospectively evaluated a database of patients referred for large (≥20 mm) nonpedunculated polyp removal. From 2000 to 2019, we compared the rates of follow-up, recurrence, adverse events, and synchronous neoplasia detection between younger patients and patients aged ≥80.

RESULTS

There were 167 patients aged ≥80 years and 1686 <80 years. Patients in the elderly group returned for surveillance less often (67.1% vs 75.1%, P = .024), had greater first follow-up recurrence rates (27.5% vs 13.8%, P < .001), but had similar adverse event rates (1.8% vs 2.8%, P = .619) compared with younger patients. Rates of synchronous neoplasia were similar and high in both groups.

CONCLUSIONS

EMR is safe and well tolerated for large polyp removal in patients over 80 years old. Patients aged ≥80 years are less likely to present for follow-up after EMR. They had a higher recurrence rate and a similarly high prevalence of synchronous precancerous lesions. Follow-up after EMR should be encouraged in the elderly, and an attempt to clear the colon of synchronous disease at the time of the initial EMR may be warranted.

The effect of PPIs Alone, PPIs plus cytoprotective agent, and H2RA plus cytoprotective agent on ulcer healing after endoscopic submucosal dissection: A prospective randomized controlled trial

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is the most effective treatment for early gastric cancer or gastric adenoma. However, ESD results in iatrogenic ulcers and postoperative bleeding from ulcers. This study aimed to evaluate the effect of using a proton pump inhibitor (PPI) alone, a PPI + rebamipide combination therapy, and an H2 receptor antagonist (H2RA) + rebamipide combination therapy on ulcer healing after ESD.

PATIENTS AND METHODS

A total of 204 patients who underwent ESD from April 2014 to July 2017 at Dong-A University Hospital were randomly assigned to the following groups: PPI-alone group, PPI + rebamipide combination therapy group, and H2RA + rebamipide combination therapy group. However, only 156 patients were studied since we excluded those who were lost to follow-up or had diseases other than early gastric cancer or gastric adenoma. Twenty-eight days after ESD, we evaluated the ulcer residual ratio, S stage rates, ulcer bleeding ratio, and gastric pH.

RESULTS

This study included 156 patients (PPI-alone group: 52 patients; PPI + rebamipide group: 52 patients; H2RA + rebamipide group: 52 patients). The ulcer residual ratios were 24.3 ± 14.2%, 17.0 ± 12.1%, and 21.0 ± 13.8% in the PPI alone, PPI + rebamipide, and H2RA + rebamipide groups, respectively (P = 0.048).

CONCLUSIONS

PPI + rebamipide was more effective in reducing the ulcer residual ratio after ESD. There was no statistical difference in ulcer stage and delayed bleeding after ESD among the groups. These findings showed that PPI + rebamipide had limited benefits after ESD.

Comparing long-term outcomes between endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) for type II esophagogastric junction neoplasm

Background

Endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) are used to remove esophagogastric junction (EGJ) neoplasm. This study aimed to compare feasibility, safety, and effectiveness between ESD and EMR to help endoscopists choose treatment methods.

Methods

A total of 130 patients with EGJ neoplasm underwent endoscopic resection, including 52 patients with EMR and 78 patients with ESD. Cap-assisted EMR (EMRC) was performed with typical sequences. Larger lesions required removal in multiple pieces (i.e., piecemeal EMR). The ESD procedures were included that marking the periphery of the lesion, submucosa injected, circumferentially cutting and submucosal dissection. Resection time, adverse events, en bloc resection rate, R0 resection rate and recurrence rate were compared between the two groups.

Results

There were no significant differences in demographic characteristics or histopathological features between the two groups. Resection time was longer in the ESD group than in the EMR group (64.4±33.9 vs. 22.1±8.0 minutes; P<0.01). Adverse events were more common in the ESD group than in the EMR group (16.7% vs. 3.8%; P=0.03), including bleeding (7.7% vs. 3.8%), perforation (5.1% vs. 0%) and stenosis (5.1% vs. 0%). The en bloc resection rate and R0 resection rate were much higher in the ESD group than in the EMR group (98.7% and 92.3% vs. 23.1% and 23.1%, respectively; P<0.01). The 5-year overall survival rate and disease-free survival rate were 100% vs. 92.0% and 100% vs. 90.1% between the ESD and EMR groups, respectively (P=0.01 and P=0.01). The 5-year cancer-specific survival rate was 100% vs. 96.0% between the ESD and EMR groups (P=0.08). The recurrence rate was lower in the ESD group than in the EMR group (0% vs. 9.6%; P=0.01).

Conclusions

ESD is an acceptable first-line endoscopic treatment for type II EGJ neoplasm, however, it is time-consuming and has a higher rate of adverse events. Furthermore, EMR is a safe and alternative technique, particularly when EMR could achieve en bloc resection.

Effect on Bleeding Prevention of an Intravenous Proton Pump Inhibitor During the Fasting Period After Endoscopic Submucosal Dissection: a Prospective, Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

No consensus has been achieved on optimal perioperative strategies for patients undergoing endoscopic submucosal dissection (ESD). The aim of this study was to investigate the effects of an intravenous (IV) proton pump inhibitor (PPI) given during the fasting period after ESD on delayed bleeding following ESD.

METHODS

This study was designed as a prospective, randomized, double-blind, placebo-controlled trial in a single center. A total of 235 patients who underwent ESD for adenoma and early gastric cancer between March 2016 and September 2018 were randomized into a PPI group and placebo group. Patients were administrated intravenous pantoprazole 40 mg daily (PPI group) or placebo (placebo group) during the fasting period 48 h after ESD (from the day of ESD to the following day, 48 h). After oral feeding (48 h after ESD), oral PPI was given to both groups for 8 weeks.

RESULTS

Among 235 patients in the intention-to-treat (ITT) and 195 in the per-protocol (PP) analysis, there was no significant difference between the PPI and control groups in major bleeding (PPI vs. placebo; 3.3% vs. 1.7%, p = 0.27) or minor bleeding (PPI vs. placebo; 7.6% vs. 4.3%, p = 0.41) after ESD. There was no significant difference in age (p = 0.28), histology (p = 0.75), tumor size (p = 0.48), or procedure time (p = 0.49) between the two groups. The only independent risk factor for major delayed bleeding was the combined use of aspirin and antiplatelet agent (OR; 12.25, 95% CI; 1.06-141.19, p = 0.04).

CONCLUSIONS

Administration of routine IV PPI during the fasting period 48 h after ESD does not reduce delayed post-ESD bleeding.

Closed laparoscopic and endoscopic cooperative surgery for early gastric cancer with difficulty in endoscopic submucosal dissection: a report of three cases

Background

Endoscopic submucosal dissection (ESD) is increasingly applied for early gastric cancer. ESD is a less invasive procedure and could be a radical treatment. However, in some cases, ESD cannot be completed owing to patient or technical factors. In such cases, which could have the potential for curative resection with ESD, standard gastrectomy is excessively invasive. Through closed laparoscopic and endoscopic cooperative surgery (LECS), gastric tumor can be precisely resected without exposing tumor cells to the abdominal cavity. Compared with standard gastrectomy, closed LECS is less invasive for the treatment of early gastric cancer.

Case presentation

We performed closed LECS for three cases of early gastric cancer after failed ESD. In all three cases, ESD was interrupted owing to technical and patient factors, including perforation, respiratory failure, and carbon dioxide narcosis. All three cases successfully underwent closed LECS with complete tumor resection and showed an uneventful postoperative course. All three patients remain alive and have experienced no complications or recurrence, with a median follow up of 30 (14–30) months.

Conclusions

Closed LECS is less invasive and useful procedure for the treatment of early gastric cancer, particularly in cases with difficulty in ESD.

Reduction in the procedure time of hybrid endoscopic submucosal dissection for early gastric neoplasms: a multi-center retrospective propensity score-matched analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) for early gastric neoplasms is still a technically difficult and time-consuming procedure. Hybrid ESD (H-ESD) involves circumferential incision with partial submucosal dissection combined with subsequent mucosal resection by snaring, wherein the newly developed device allows us to perform H-ESD using a single device. This study aimed to determine the clinical outcomes of H-ESD compared with conventional ESD (C-ESD) for early gastric neoplasms.

METHODS

In this multi-center, retrospective study, using propensity score-matched analysis, we reviewed the charts of patients with early gastric neoplasms smaller than 20 mm treated with H-ESD or C-ESD at three hospitals between January 2017 and October 2018. The primary outcome was the procedure time, and the secondary outcomes were other factors, including the en bloc resection rate, complete resection rate, curative resection rate, and rate of adverse events.

RESULTS

Among 215 patients, 29 underwent H-ESD and 186 underwent C-ESD; 29 pairs were created by propensity score matching. In the H-ESD group, 82.8% of lesions met the absolute indication [mucosal lesions limited to 20-mm diameter, dominated by differentiated adenocarcinoma without ulcer (scar)] for endoscopic resection (ER). As a result, the procedure time of H-ESD was significantly shorter than that of C-ESD [20 (interquartile range, 12-27) min versus 40 (30-50) min; p < 0.001]. There was no significant difference in the secondary outcomes between the two groups.

CONCLUSION

H-ESD contributed to reduced procedure time. Therefore, H-ESD could be an alternative endoscopic treatment for gastric neoplasms when the lesion fulfils the absolute indication for ER.

Efficacy and Feasibility of Magnifying Blue Laser Imaging without Biopsy Confirmation for the Diagnosis of the Demarcation of Gastric Tumors: A Randomized Controlled Study

BACKGROUND

Accurate diagnosis of the demarcation line (DL) of gastric tumors is essential for curative complete resection by endoscopic submucosal dissection (ESD). It is controversial to perform only magnifying endoscopy for diagnosing the DL of gastric tumors prior to ESD. This study aimed to evaluate the diagnostic accuracy for the DL of gastric adenomas and well-differentiated adenocarcinomas using only magnifying blue laser imaging (M-BLI) compared with that using both M-BLI and biopsy confirmation.

METHODS

In this prospective, single-center study, 96 well-differentiated adenocarcinomas and 32 gastric adenomas were enrolled between July 2015 and December 2016. A total of 122 lesions with a clear DL on M-BLI were randomly allocated to undergo M-BLI only (the M-BLI group) or M-BLI with biopsy confirmation (the M-BLI-BC group), performed as biopsies in 4 directions from noncancerous tissues ≈ 5 mm outside the lesion before ESD. The primary end point was to clarify the noninferiority of M-BLI without biopsy confirmation compared with that with biopsy confirmation, in terms of the diagnostic accuracy and complete resection.

RESULTS

There were no significant differences in sex, median age, color, circumference, macroscopic type, biopsy-based diagnosis, and Helicobacter pylori infection between the 2 groups. The diagnostic accuracy for the DL was 100 and 95.0% and the complete resection was 100 and 100% in the M-BLI and M-BLI-BC groups, respectively.

CONCLUSION

The diagnostic ability of M-BLI is excellent in diagnosing the demarcation of gastric adenoma and well-differentiated adenocarcinoma. Biopsy confirmation is not needed for these lesions with a clear DL by M-BLI.

Tip-in endoscopic mucosal resection for large colorectal sessile polyps

BACKGROUND

Tip-in endoscopic mucosal resection (EMR) is a modified EMR technique using which en bloc resection of large colorectal sessile polyps can be performed; however, its usefulness for colorectal sessile polyps of > 20 mm has not been reported. This study examined treatment outcomes of tip-in and conventional EMR for large colorectal sessile polyps of ≥ 20 mm.

METHODS

This was a retrospective case-control study conducted at a single tertiary center in Japan. Subjects included those with large colorectal sessile polyps of ≥ 20 mm, excluding pedunculated-type polyps, who underwent endoscopic resection between January 2010 and January 2019. The primary outcome was endoscopic treatment outcomes when using tip-in and conventional EMR, and the secondary outcome was the local recurrence rate after endoscopic treatment.

RESULTS

Forty-three colorectal lesions were treated using tip-in EMR and 83 using conventional EMR. Tip-in EMR had a significantly higher en bloc resection rate (90.7% vs. 69.8.%), and significantly shorter treatment duration (6.64 ± 0.64 min vs. 10.47 ± 0.81 min) than conventional EMR. However, for lesions > 30 mm, en bloc resection rate was 50.0% and 52.6% for tip-in and conventional EMR, respectively, indicating no significant difference. Perforation rates with tip-in and conventional EMR were 4.6% and 3.6%, respectively, indicating no significant difference. Local recurrence was examined in 80 cases who were followed up for > 6 months after endoscopic resection; recurrence rate was 0% and 7.0% in tip-in and conventional EMR cases, respectively, without significance difference.

CONCLUSIONS

Tip-in EMR showed high en-block resection rate, particularly in polyps of < 30 mm, and no residual tumor was found. This technique is a potential endoscopic treatment alternative for large colorectal sessile polyps of ≥ 20 mm.

Conventional versus traction-assisted endoscopic submucosal dissection for large esophageal cancers: a multicenter, randomized controlled trial (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is widely used as a minimally invasive treatment for large esophageal cancers, but prolonged procedure duration and life-threatening adverse events remain matters of concern. We aimed to determine whether traction-assisted ESD (TA-ESD) is superior to conventional ESD in terms of technical outcomes.

METHODS

A superiority, randomized, phase III trial was conducted at 7 institutions across Japan. Patients with large esophageal cancer (defined as tumor diameter >20 mm) were eligible for this study. Enrolled patients were randomly assigned to undergo conventional ESD or TA-ESD. The primary endpoint was ESD procedure duration.

RESULTS

Two hundred forty-one patients were recruited and randomized. On applying exclusion criteria, 117 and 116 patients who underwent conventional ESD and TA-ESD, respectively, were included in the baseline analysis. In 1 patient, conventional ESD was discontinued because of severe perforation. Thus, the final analysis included 116 patients per group (primary analysis). The ESD procedure duration was significantly shorter for TA-ESD than for conventional ESD (44.5 minutes vs 60.5 minutes, respectively; P < .001). Moreover, no adverse events were noted in the TA-ESD group. The rate of horizontal margin involvement did not differ between the groups (10.3% vs 6.9% for conventional ESD and TA-ESD, respectively; P = .484).

CONCLUSIONS

TA-ESD was superior to conventional ESD in terms of procedure duration and was not associated with any adverse events. TA-ESD should be considered the procedure of choice for large esophageal cancers. (Clinical trial registration number: UMIN000024080.).

Optoacoustic mesoscopy for biomedicine

Fuelled by innovation, optical microscopy plays a critical role in the life sciences and medicine, from basic discovery to clinical diagnostics. However, optical microscopy is limited by typical penetration depths of a few hundred micrometres for in vivo interrogations in the visible spectrum. Optoacoustic microscopy complements optical microscopy by imaging the absorption of light, but it is similarly limited by penetration depth. In this Review, we summarize progress in the development and applicability of optoacoustic mesoscopy (OPAM); that is, optoacoustic imaging with acoustic resolution and wide-bandwidth ultrasound detection. OPAM extends the capabilities of optical imaging beyond the depths accessible to optical and optoacoustic microscopy, and thus enables new applications. We explain the operational principles of OPAM, its placement as a bridge between optoacoustic microscopy and optoacoustic macroscopy, and its performance in the label-free visualization of tissue pathophysiology, such as inflammation, oxygenation, vascularization and angiogenesis. We also review emerging applications of OPAM in clinical and biological imaging.

Potential of temperature-response collagen-genipin sols as a novel submucosal injection material for endoscopic resection

Background and study aims  We developed a novel submucosal (SM) injection material that contained pepsin-solubilized collagen (PSC), genipin (Ge) and phosphate buffer (PB). The aim of this study was to validate safety and usability of it for endoscopic resection (ER). Materials and methods  In preliminary studies, 1) appropriate warming time and concentration of Ge, and concentration of NaCl in PB, 2) storage modulus of PSC, Ge, and PB mixture (PSC/Ge), and PSC as a mechanical property, 3) histological finding after injection, and histological toxicity of PSC/Ge was evaluated. We injected PSC/Ge, PSC, sodium hyaluronate (SH), dextrose (DW), and normal saline (NS) into SM of resected porcine stomach. We compared mean height of mucosal elevation after immediate injection (MH) and mean retaining rate at 60 minutes (MR) as ex vivo study. Results  Optimal condition of PSC/Ge was Ge 5.5 mMol with 24 hours worming time and NaCl 280 mMol. PSC/Ge had better mechanical property than PSC. It was efficiently integrated and confined to the SM with acceptable toxicity. MH of PSC/Ge (5.1 ± 0.74 mm) and PSC (4.8 ± 0.84 mm) were significantly higher than NS (3.2 ± 0.84 mm). MR of PSC/Ge (100 ± 0.0%) was significantly higher than NS (61.7 ± 11.2%), DW (58.3 ± 11.8%) and SH (61.8 ± 8.6%). Conclusion  PSC/Ge and PSC has potential to be safe and usable for ER. PSC/Ge was better than PSC because of better mechanical property than PSC.

Solutions for submucosal injection: What to choose and how to do it

During the past decades, endoscopic resection techniques have gradually improved and gained more importance for the management of premalignant lesions and early cancers. These endoscopic resection techniques can be divided in 3 major groups: snare polipectomy, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). The use of submucosal injection is essential for the majority of EMR techniques and is an integral part of ESD, whereas during polipectomy it is not crucial in most cases except to prevent bleeding in large polyps and/or those with large stalks as an alternative to mechanical methods. Injection provides a lifting up effect of the lesion separating it from the muscular layer, thereby reducing thermal injury and the risk of perforation and bleeding while also facilitating en-bloc resection by improving technical feasibility. With this work, we aim to review the most common endoscopic resection techniques and the importance of submucosal injection in each one of them. For that, we present some of the most commonly used submucosal injection solutions, taking into account their advantages and disadvantages. We also discuss, based on current recommendations and our own experience, how and when to preform submucosal injection, depending on lesions features and endoscopic resection technique that´s being used, to assure complete resection and to prevent associated adverse events. Finally, we also present and discuss some new proposed submucosal injection solutions, endoscopic resection techniques and devices that may have a major impact on the future of therapeutic endoscopy.

Characteristics of a Surgical Snare Using Microwave Energy

Currently, minimally invasive treatments that insert various treatment devices into an endoscope are actively being performed. A high-frequency (HF) snare is commonly used as an energy device inserted into an endoscope. However, using a high-frequency snare, problems usually occur, such as the obstruction of the visual field caused by smoke. On the other hand, microwave heating produces less smoke and provides a better visual field. In this study, a snare using microwave energy inserted into an endoscope is proposed, and its characteristics are evaluated.

Sclerotherapy needle injections can expand the subserosal and muscularis propria layers and cause a stable mucosal lift in ESD/EMR patients

Background

A mucosal lift is needed for ESD and EMR. Most lifts are made via sclerotherapy needle injection. The firm push needed to penetrate the mucosa often leaves the needle tip in the deep wall. The needle is next withdrawn and fluid injected until a sharp lift (due to submucosal expansion) begins to form; the needle is then held steady and the injection finished. The initial injection may result in a subtle deep lift that resolves quickly. It was the authors’ belief that only submucosal expansion could lead to a stable mucosal lift. A colonic ESD case in which a polyp was inadvertently resected via needle knife in an expanded subserosal plane led to a questioning of this position. This study’s purpose was to determine if stable deep wall mucosal lifts can be generated via bowel wall injection.

Methods

Transmucosal and intramural injections into bovine large bowel were carried out. Stable lifts and lift cross sections were made and examined grossly and histologically to determine the location of the lift fluid. Clinical ESD videos were also reviewed.

Results

Over 200 intact and cross-sectioned lifts were assessed. Gross inspection revealed two types of lifts (superficial and deep), whereas cross sections and histologic analyses revealed examples of stable expansion of the submucosal, muscularis propria, and subserosal layers post injection. Clinical “deep” lifts were also found. Superficial lifts are more focal and taller, whereas deep wall lifts are broader and less prominent.

Conclusion

Stable deep wall mucosal lifts occur and are likely due to the deep starting point of the needle post insertion. If ESD/EMR are attempted with a deep lift, the chances of failure or perforation are high. Lifts must be carefully scrutinized before starting ESD/EMR. Other means of lift establishment should be evaluated and considered.

Electronic supplementary material

The online version of this article (10.1007/s00464-018-6521-5) contains supplementary material, which is available to authorized users.