Endoscopic management of mucosal lesions in the gastrointestinal tract

A Roadmap for the Human Gut Cell Atlas

The number of studies investigating the human gastrointestinal tract using various single-cell profiling methods has increased substantially in the past few years. Although this increase provides a unique opportunity for the generation of the first comprehensive Human Gut Cell Atlas (HGCA), there remains a range of major challenges ahead. Above all, the ultimate success will largely depend on a structured and coordinated approach that aligns global efforts undertaken by a large number of research groups. In this Roadmap, we discuss a comprehensive forward-thinking direction for the generation of the HGCA on behalf of the Gut Biological Network of the Human Cell Atlas. Based on the consensus opinion of experts from across the globe, we outline the main requirements for the first complete HGCA by summarizing existing data sets and highlighting anatomical regions and/or tissues with limited coverage. We provide recommendations for future studies and discuss key methodologies and the importance of integrating the healthy gut atlas with related diseases and gut organoids. Importantly, we critically overview the computational tools available and provide recommendations to overcome key challenges.

[Analysis of endoscopic and pathological features of gastric adenomatous polyps and risk factors for canceration]

OBJECTIVE

To investigate the endoscopic and pathological characteristics of gastric adenomatous polyps and to assess the potential risk factors for canceration of gastric adenomatous polyps.

METHODS

The endoscopic and pathological characteristics of the patients with gastric adenomatous polyps from January 1, 2005 to December 31, 2019 were summarized retrospectively, and the risk factors of canceration were analyzed.

RESULTS

A total of 125 patients with gastric adenomatous polyps were included, 51.20% of whom were females. The average age was (66.7±12.3) years. 64.80% of patients with gastric adenomatous polyps equal or more than 65 years old, and only 5.60% of the patients less than 45 years old. Adenomatous polyps were mostly distributed in the corpus and antrum with 40.80% and 32.80%, respectively. The majority of them were single (90.40%) and sessile (76.81%). 65.4% of adenomatous polyps were no more than 1.0 cm in diameter, and 23.20% of patients with adenomatous polyps were combined with hyperplastic polyps and/or fundus glandular polyps, and 1.60% had both pathological types of polyps. 58.62% (17/29) patients with hyperplastic polyps and/or fundus glandular polyps had multiple polyps. 1.60% (2/125) of the patients had gastric neuroendocrine tumor of G1 stage. Synchronous gastric cancer was detected in 13.60% (17/125) of the patients with adenomatous polyps, and the proportion of low-grade intraepithelial neoplasia was 18.40% (23/125). The main types of synchronous gastric cancer were progressive (70.59%) and undifferentiated (66.67%). Chronic atrophic gastritis with intestinal metaplasia was found in 52.80% of the patients, and autoimmune gastritis accounted for 11.20%. The positive rate of Helicobacter pylori was 21.60%. The canceration rate of gastric adenomatous polyps was 20.80%. The cancer was mainly differentiated, but there was sigmoid ring cell carcinoma as well. Diameter of >1.0 cm (OR=5.092, 95%CI: 1.447-17.923, P=0.011), uneven surface morphology and erosion (OR=13.749, 95%CI: 1.072-176.339, P=0.044) were independent risk factors of adenomatous polyps.

CONCLUSION

The synchronous gastric cancer is common and the canceration of gastric adenomatous polyps is high with diameter and surface morphology as independent risk factors. We should pay attention to the identification of the pathological types of polyps and the evaluation of the whole gastric mucosa during the endoscopic examination.

Endoscopic management of superficial nonampullary duodenal tumors: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that all duodenal adenomas should be considered for endoscopic resection as progression to invasive carcinoma is highly likely.Strong recommendation, low quality evidence. 2: ESGE recommends performance of a colonoscopy, if that has not yet been done, in cases of duodenal adenoma.Strong recommendation, low quality evidence. 3: ESGE recommends the use of the cap-assisted method when the location of the minor and/or major papilla and their relationship to a duodenal adenoma is not clearly established during forward-viewing endoscopy.Strong recommendation, moderate quality evidence. 4: ESGE recommends the routine use of a side-viewing endoscope when a laterally spreading adenoma with extension to the minor and/or major papilla is suspected.Strong recommendation, low quality evidence. 5: ESGE suggests cold snare polypectomy for small (< 6 mm in size) nonmalignant duodenal adenomas.Weak recommendation, low quality evidence. 6: ESGE recommends endoscopic mucosal resection (EMR) as the first-line endoscopic resection technique for nonmalignant large nonampullary duodenal adenomas.Strong recommendation, moderate quality evidence. 7: ESGE recommends that endoscopic submucosal dissection (ESD) for duodenal adenomas is an effective resection technique only in expert hands.Strong recommendation, low quality evidence. 8: ESGE recommends using techniques that minimize adverse events such as immediate or delayed bleeding or perforation. These may include piecemeal resection, defect closure techniques, noncontact hemostasis, and other emerging techniques, and these should be considered on a case-by-case basis.Strong recommendation, low quality evidence. 9: ESGE recommends endoscopic surveillance 3 months after the index treatment. In cases of no recurrence, a further follow-up endoscopy should be done 1 year later. Thereafter, surveillance intervals should be adapted to the lesion site, en bloc resection status, and initial histological result. Strong recommendation, low quality evidence.

Is a Fundamental Design Change for Gastrointestinal Endoscopes Required?

Since the first fiberoptic instruments, gastrointestinal endoscopy has shaped the field of gastroenterology and is now a key diagnostic and therapeutic tool. Compared with the initial fiberoptic endoscopes state-of-the-art optical chips (or charge-coupled device technology) allowed a quantum leap in image quality. Despite these advances, gastrointestinal endoscopy is far from being perfect. The diagnostic yield (eg, for adenoma detection rates) is highly operator dependent and there is still the need for sedation or even anesthesia to address discomfort during the procedure. Despite highly standardized cleaning and high-level disinfection the reuse of contemporary (and difficult to clean) endoscopes with multiple channels exposes patients to the risk of transmission of infections. Artificial intelligence and pattern recognition should eliminate interindividual variability including polyp detection rates, self-propelled, and (potentially remotely controlled) scopes with a soft shaft could reduce the discomfort during procedures and abolish the need for sedation and anesthesia altogether and single-use designs should eliminate the risk of patient-to-patient transmission of infections. While these innovations are feasible and could be implemented rapidly utilizing available technology, they require a paradigm shift affecting all levels of the value chain from the supplier of the instruments to the end-users. Some may negate the need for a paradigm shift, but it is evident that a major redesign of the endoscopic equipment is overdue to fully utilize novel technologies and most importantly ensure the best possible outcomes for patients.

Application of endoscopic submucosal dissection in duodenal space-occupying lesions

BACKGROUND

Endoscopic submucosal dissection (ESD) has been advocated by digestive endoscopists because of its comparable therapeutic effect to surgery, reduced trauma, faster recovery, and fewer complications. However, ESD for lesions of the duodenum is more challenging than those occurring at other levels of the gastrointestinal tract due to the thin intestinal wall of the duodenum, narrow intestinal space, rich peripheral blood flow, proximity to vital organs, and high risks of critical adverse events including intraoperative and delayed bleeding and perforation. Because of the low prevalence of the disease and the high risks of severe adverse events, successful ESD for lesions of the duodenum has rarely been reported in recent years.

AIM

To investigate the efficacy and safety of ESD in the treatment of duodenal space-occupying lesions.

METHODS

Clinical data of 24 cases of duodenal lesions treated by ESD at the Digestive Endoscopy Center of the Affiliated Hospital of Qingdao University from January 2016 to December 2019 were retrospectively analyzed.

RESULTS

All of the 24 cases from 23 patients underwent ESD treatment for duodenal space-occupying lesions under general anesthesia, including 15 male and 8 female patients, with a mean age of 58.5 (32.0-74.0) years. There were 12 lesions (50%) in the duodenal bulb, 9 (37.5%) in the descending part, and 3 (12.5%) in the ball-descending junction. The mean diameter of the lesion was 12.75 (range, 11-22) mm. Thirteen lesions originated from the mucosa, of which 4 were low-grade intraepithelial neoplasia, 3 were hyperplastic polyps, 2 were chronic mucositis, 2 were adenomatous hyperplasia, 1 was high-grade intraepithelial neoplasia, and 1 was tubular adenoma. Eleven lesions were in the submucosa, including 5 neuroendocrine neoplasms, 2 cases of ectopic pancreas, 1 stromal tumor, 1 leiomyoma, 1 submucosal duodenal adenoma, and 1 case of submucosal lymph follicular hyperplasia. The intraoperative perforation rate was 20.8% (5/24), including 4 submucosal protuberant lesions and 1 depressed lesion. The mean length of hospital stay was 5.7 (range, 3-10) d, and the average follow-up time was 25.8 (range, 3.0–50.0) mo. No residual disease or recurrence was found in all patients, and no complications, such as infection and stenosis, were found during the follow-up period.

CONCLUSION

ESD is safe and effective in the treatment of duodenal lesions; however, the endoscopists should pay more attention to the preoperative preparation, intraoperative skills, and postoperative treatment.

Effect of prophylactic clipping on adverse events after colorectal endoscopic resection: A meta-analysis

BACKGROUND

The effect of prophylactic hemoclip placement on the risk of adverse events such as delayed bleeding and perforation after colorectal polypectomy is still unclear. Its efficiency has not been confirmed and there is no consensus on the usefulness of prophylactic clipping.

AIM

To assess the efficacy of prophylactic clipping on adverse events after endoscopic resection of colorectal polyps.

METHODS

We performed a search of PubMed, EMBASE, Cochrane library, and Wanfang databases for studies comparing the effect of clipping vs no clipping on adverse events following endoscopic resection. The quality of the included studies was performed. Statistical analysis was performed using Revman5.3 software.

RESULTS

We identified seven eligible randomized trials from the database search, involving a total of 3777 patients, which included 1880 patients who used prophylactic hemoclips (clip group) and 1897 who did not use (no clip group). Meta-analysis results showed that the delayed bleeding rate of the clip group was significantly lower than that of the no clip group (2.55% vs 4.48%, P = 0.01, 95%CI: 0.40-0.80). There was no significant difference in postoperative perforation rate between the clip group and no clip group (0.66% vs 1.04%, P = 0.42, 95%CI: 0.21-1.92). Subgroup analysis showed that the prophylactic effect on delayed bleeding was mainly observed in polyps with a size of ≥ 20 mm, and the preventive effect in polyps less than 20 mm was poor (RR = 1.18, 95%CI: 0.62-2.23, P = 0.62; RR = 0.47, 95%CI: 0.29-0.77, P = 0.003). There was no significant difference in the effect of prophylactic hemoclips on the prevention of delayed bleeding after resection of proximal and distal colonic polyps (RR = 0.57, 95%CI: 0.18-1.80, P = 0.34; RR = 0.78, 95%CI: 0.06-10.33, P = 0.85).

CONCLUSION

Prophylactic hemoclips can prevent the occurrence of delayed bleeding after colorectal polypectomy, which is mainly observed in the lesions ≥ 20 mm. In addition, hemoclips have little preventive effect on postoperative perforation.

Safety of endoscopic mucosal resection (EMR) of large non-pedunculated colorectal adenomas in the elderly

BACKGROUND

Endoscopic mucosal resection (EMR) has been proven to be safe and effective for the treatment of colorectal adenomas. However, data are limited on the safety of this technique for large polyps and in elderly patients. Aims of our study were to examine the bleeding and perforation rates in patients with large non-pedunculated adenomas (≥20mm) and to evaluate the influence of size (≥40mm) and age (≥75 years) on the complication rates.

METHODS

In this multicenter retrospective study, patients who underwent EMR of non-pedunculated adenomas ≥20mm between January 2012 and March 2016 were included. The demographics of the patients, the use of antithrombotic drugs, size of the polyps, type of resection, pathology report, occurrence of post-polypectomy bleeding, and perforation- and recurrence rate were collected.

RESULTS

In 343 patients, 412 adenomas were removed. Eighty patients (23.3%) were ≥75 years of age, 138 polyps (33.5%) were ≥40mm. Bleeding complications were observed in 28 cases (6.8%) and were found significantly more frequent in adenomas ≥40mm, independent of the use of antithrombotic therapy. Five perforations (1.2%) were described, not related to the size of the polyp. There was no significant difference in complication rates between patients <75 years and patients ≥75 years. Bleeding complications rates were significantly higher in patients receiving double antithrombotic therapy.

CONCLUSION

EMR is safe in elderly patients. EMR of adenomas of ≥40mm was associated with more bleeding complications. Future studies should address how the bleeding rates can be reduced in these patients, especially in those who use double antithrombotic treatment.