Effect of polyglycolic acid sheet plus esophageal stent placement in preventing esophageal stricture after endoscopic submucosal dissection in patients with early-stage esophageal cancer: A randomized, controlled trial

Research on triamcinolone-loaded thermosensitive chitosan hydrogels for preventing esophageal stricture induced by endoscopic submucosal dissection

Early-stage esophageal cancer is primarily treated by endoscopic submucosal dissection (ESD). However, extensive mucosal dissection creates a significant risk of postoperative esophageal stricture. Clinically, postoperative stricture can be prevented by glucocorticoids; however, there are drawbacks to both systemic and local administration of glucocorticoids, and improving drug administration methods is crucial. In this study, we developed a chitosan-based thermosensitive hydrogel for triamcinolone (TA) delivery. Our results indicated that the hydrogel remains liquid at low temperatures and can be injected into the esophageal wound site through an endoscopic biopsy channel. Upon reaching body temperature, the hydrogel undergoes spontaneous gelation and firmly adheres to the wound surface. The liquid phase enables convenient and precise delivery, while the gel phase achieves remarkable adhesion, tensile strength, and resistance to degradation. Moreover, the hydrogel exhibited an extended release duration of >10 days when loaded with a 10 mg dose. In vitro studies revealed that the hydrogel suppresses the proliferation and fibrogenesis of human scar fibroblasts (HKF). In a rat skin dermal defect model, the hydrogel attenuated keloid formation during the healing process. Consequently, the chitosan-based thermosensitive hydrogel developed in this study for triamcinolone delivery may be an effective tool for preventing post-ESD esophageal stricture.

Progress in the treatment and prevention of esophageal stenosis after endoscopic submucosal dissection

The primary treatment for early esophageal cancer and precancerous lesions is endoscopic submucosal dissection (ESD). However, this approach leads to a high incidence of postoperative esophageal stenosis, which can significantly impact a patient's quality of life. While various methods are available to prevent post-ESD esophageal stenosis, their effectiveness varies. Therefore, this study aims to provide an overview of the currently employed methods for preventing post-ESD esophageal stenosis in clinical practice in view of assisting clinical practitioners.

Curative criteria for endoscopic treatment of oesophageal squamous cell cancer

Endoscopic treatment of early oesophageal squamous cell carcinoma is widely accepted. ESD (Endoscopic Submucosal Dissection), which allows en bloc resection regardless of size, provides resected specimens that facilitate histological evaluation of curability. In the histological investigation, the determination of tumor depth, lymphovascular involvement, and lateral and vertical margins play a great role in the assessment of curability. The diagnosis of lymphovascular invasion, in particular, is enhanced by the addition of immunostaining. The long-term outcome of ESD is comparable to that of oesophagectomy, and ESD may be the first-line treatment for early-stage oesophageal cancer due to its fewer complications. Surveillance after curative resection is also imperative because oesophageal cancer is often characterized by the concept of field cancerization, which results in metachronous multiple primary lesions.

Prospects of polyglycolic acid sheets for the treatment of esophageal stricture after esophageal endoscopic submucosal dissection

Esophageal cancer is the seventh most common type of cancer and the sixth leading cause of cancer -related mortality worldwide. Endoscopic submucosal dissection (ESD) is widely used for the resection of early esophageal cancer. However, post-ESD esophageal stricture is a common long-term complication, which requires attention. Patients with post-ESD esophageal stricture often experience dysphagia and require multiple dilatations, which greatly affects their quality of life and increases healthcare costs. Therefore, to manage post-ESD esophageal stricture, researchers are actively exploring various strategies, such as pharmaceutical interventions, endoscopic balloon dilation, and esophageal stenting. Although steroids-based therapy has achieved some success, steroids can lead to complications such as osteoporosis and infection. Meanwhile, endoscopic balloon dilatation is effective in the short term, but is prone to recurrence and perforation. Additionally, esophageal stenting can alleviate the stricture, but is associated with discomfort during stenting and the complication of easy displacement also present challenges. Tissue engineering has evolved rapidly in recent years, and hydrogel materials have good biodegradability and biocompatibility. A novel type of polyglycolic acid (PGA) sheets has been found to be effective in preventing esophageal stricture after ESD, with the advantages of a simple operation and low complication rate. PGA membranes act as a biophysical barrier to cover the wound as well as facilitate the delivery of medications to promote wound repair and healing. However, there is still a lack of multicenter, large-sample randomized controlled clinical studies focused on the treatment of post-ESD esophageal strictures with PGA membrane, which will be a promising direction for future advancements in this field.

Prevention of esophageal stricture after endoscopic submucosal dissection of squamous cell carcinoma using a 20-French nasogastric tube combined with oral steroid administration

BACKGROUND

Esophageal stricture is a major complication after esophageal endoscopic submucosal dissection (ESD) and when the mucosal defect exceeds 3/4 of the circumference. Various preventive methods have been reported to prevent stenosis. However, in the case of circumferential ESD, there is no way to prevent luminal stenosis effectively. This retrospective study aimed to evaluate the efficacy of 20-French nasogastric tubes (NGT) combined with oral steroids for the prevention of esophageal stricture after endoscopic submucosal dissection.

METHODS

Between January 2012 and December 2021, we enrolled 57 patients with post-ESD mucosal defects exceeding 3/4 of the esophageal circumference. Of them, the initial seven patients received oral steroid therapy and the subsequent 50 patients received 20-French NGT placements combined with oral steroid therapy. We retrospectively evaluated the rates of strictures and refractory strictures and explored risk factors for strictures with 20-French NGT.

RESULTS

The overall esophageal stricture rate was 42.1% (24/57). In the noncircumferential group, the esophageal stricture rate in patients with only oral steroid to prevent esophageal stricture was 85.7% (6/7), while the esophageal stricture rate was only 4.3% (1/23) in those with 20-French NGT placements and oral steroid. All 27 patients with whole-circumferential resection received 20-French NGT placements. The stricture rate was 63.0% (17/27), and the refractory stricture rate was 17.6% (3/27).

CONCLUSION

Using a 20-French NGT placement combined with oral steroid administration is an easy and safe alternative to prevent esophageal stricture after ESD, especially for patients with noncircumferential mucosal defects. Further studies are needed to develop an effective stricture prevention method for post-ESD whole-circumferential mucosal defects of the esophagus.

Endoscopic submucosal dissection techniques and technology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review

ESGE suggests conventional endoscopic submucosal dissection (ESD; marking and mucosal incision followed by circumferential incision and stepwise submucosal dissection) for most esophageal and gastric lesions. ESGE suggests tunneling ESD for esophageal lesions involving more than two-thirds of the esophageal circumference. ESGE recommends the pocket-creation method for colorectal ESD, at least if traction devices are not used. The use of dedicated ESD knives with size adequate to the location/thickness of the gastrointestinal wall is recommended. It is suggested that isotonic saline or viscous solutions can be used for submucosal injection. ESGE recommends traction methods in esophageal and colorectal ESD and in selected gastric lesions. After gastric ESD, coagulation of visible vessels is recommended, and post-procedural high dose proton pump inhibitor (PPI) (or vonoprazan). ESGE recommends against routine closure of the ESD defect, except in duodenal ESD. ESGE recommends corticosteroids after resection of  > 50 % of the esophageal circumference. The use of carbon dioxide when performing ESD is recommended. ESGE recommends against the performance of second-look endoscopy after ESD. ESGE recommends endoscopy/colonoscopy in the case of significant bleeding (hemodynamic instability, drop in hemoglobin > 2 g/dL, severe ongoing bleeding) to perform endoscopic hemostasis with thermal methods or clipping; hemostatic powders represent rescue therapies. ESGE recommends closure of immediate perforations with clips (through-the-scope or cap-mounted, depending on the size and shape of the perforation), as soon as possible but ideally after securing a good plane for further dissection.

Combined treatment of refractory benign stricture after esophageal endoscopic mucosal dissection: A case report

BACKGROUND

Endoscopic submucosal dissection (ESD) post-procedure stricture is a relatively common long-term complication following ESD treatment. A range of approaches has been implemented for the treatment of post-procedural stricture using endoscopic techniques such as endoscopic dilation, self-expandable metallic stent insertion, local steroid injection in the esophagus, oral steroid administration, radial incision and cutting (RIC). The actual efficacy of these different therapeutic options is highly variable, and uniform international standards for the prevention or treatment of stricture.

CASE SUMMARY

In this report, we describe the case of a 51-year-old male diagnosed with early esophageal cancer. To protect against esophageal stricture, the patient was administered oral steroids and underwent self-expandable metallic stent insertion for 45 d. Despite these interventions, stricture was detected at the lower edge of the stent following its removal. The patient remained refractory to multiple rounds of endoscopic bougie dilation treatment, and thus suffered from complex refractory benign esophageal stricture. As such, RIC combined with bougie dilation and steroid injection was employed to treat this patient more effectively, ultimately achieving satisfactory therapeutic efficacy.

CONCLUSION

Combination of RIC, dilation, and steroid injection can be safely and effectively implemented to treat cases of post-ESD refractory esophageal stricture.

Endoscopic treatment of early esophageal cancer with decompensated cirrhosis and successful prevention of postoperative stenosis: A case report

The management of gastrointestinal tumors with decompensated cirrhosis is extremely challenging. Patients often present with poor basic condition and coagulation function, and nutritional deficiency. Furthermore, postoperative recovery is difficult and so the majority of patients refuse surgery. The present study reports the case of a 73-year-old man with decompensated cirrhosis and early esophageal cancer. At the discretion of the patient and their family, a simultaneous approach was used to treat esophagogastric varices and perform a mucosal dissection of the early esophageal cancer via endoscopy. Post-surgery, multiple polyglycolic acid sheets were attached to the esophageal dissection wound. At >2 months post-surgery, an endoscopic re-examination of the patient showed that the esophageal mucosa had healed well, and there was no resistance detected via ordinary endoscopy. The main objective of the present study was to highlight the feasibility and safety of endoscopic treatment for patients with decompensated liver cirrhosis complicated with early esophageal cancer, and to provide a new treatment strategy for patients at high risk of esophageal stenosis after endoscopic mucosal dissection.

Allogeneic transplantation of epidermal cell sheets followed by endoscopic submucosal dissection to prevent severe esophageal stricture in a porcine model

Introduction

Endoscopic submucosal dissection (ESD) is a minimally invasive treatment for early esophageal cancer. However, large mucosal defects after esophageal ESD result in refractory strictures. In the present study, we histologically evaluated the endoscopic transplantation of allogeneic epidermal cell sheets (ECSs) as a feasible therapy for preventing esophageal stricture after circumferential ESD in a porcine model.

Methods

Epidermal cells were isolated from the skin tissue of allogeneic pigs and cultured on temperature-responsive cell culture inserts for 2 weeks. Transplantable ECSs were harvested by reducing the temperature and endoscopically transplanting the sheets to ulcer sites immediately after esophageal ESD. The engraftment of transplanted ECSs was then evaluated in two pigs at 7 days after transplantation. Next, ten pigs were divided into two groups to evaluate the endoscopic transplantation of allogeneic ECSs for the prevention of esophageal strictures after ESD. Allogeneic ECSs were transplanted immediately after esophageal ESD in the transplantation group (n = 5), whereas the control group (n = 5) did not undergo transplantation.

Results

Most of the transplanted allogeneic ECSs were successfully engrafted at the ulcer sites in the early phase. Fluorescence in situ hybridization analysis revealed that several allogeneic cells were present in the transplanted area at 7 days after ESD. At 14 days after ESD, significant differences in body weight loss, dysphagia scores, and mucosal strictures were observed between the control and transplantation groups. Transplanting allogeneic ECSs after esophageal ESD promotes mucosal healing and angiogenesis and prevents excessive inflammation and granulation tissue formation.

Conclusions

Endoscopic and histological analyses revealed that allogeneic ECSs promoted artificial ulcer healing after ESD, preventing esophageal strictures after ESD.

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Large mucosal defects of the esophagus cause severe strictures.

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Allogeneic epidermal cell sheets promote esophageal mucosal healing.

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Allogeneic epidermal cell sheets induce angiogenesis in esophageal ulcers.

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Allogeneic epidermal cell sheets prevent excessive inflammation in esophageal ulcers.

The role of polyglycolic acid sheets in the management of post-endoscopic submucosal dissection gastrointestinal bleeding and esophageal stricture: A PRISMA compliant systematic review and meta-analysis

BACKGROUND

As a relatively minimally invasive technique, endoscopic submucosal dissection (ESD) is widely used for the treatment of gastrointestinal lesions. However, it is associated with complications, such as postoperative bleeding, stricture, and perforation. A covering method using polyglycolic acid (PGA) sheets for ESD-induced ulcers has been reported to be effective in reducing the risk of post-ESD bleeding and esophageal stricture. Herein, we conducted a systematic review and meta-analysis to evaluate the role of PGA sheets in the prevention of gastrointestinal bleeding and esophageal stricture after ESD.

METHODS

We searched PubMed, Web of Science, and the Cochrane Library databases on October 15, 2019. All eligible articles were selected based on the predefined inclusion and exclusion criteria. The main outcomes were the rates of post-ESD gastrointestinal bleeding and esophageal stricture. Cochrane's Q statistic and I2 test were used to identify heterogeneity between the studies. When there was no obvious heterogeneity (I2 < 50%, P > .1), a fixed-effect model was used. When there was obvious heterogeneity (I2 > 50%, P < .1), a random effect model was used. Funnel plots and the Egger regression test were used to assess publication bias.

RESULTS

Fifteen articles were included in the meta-analysis, of which 7 were exclusively about the use of PGA sheets to prevent postoperative gastrointestinal bleeding, and the remaining reported the use of PGA sheets to prevent postoperative esophageal stenosis. Our analysis showed that preventive therapy with PGA sheets decreased the rates of post-ESD gastrointestinal bleeding (risk ratio [RR] = 0.35, 95% confidential interval [CI]: 0.19-0.64, P < .001) and esophageal stricture (RR = 0.46, 95% CI: 0.27-0.79, P = .005), and the gastrointestinal bleeding and esophageal stricture rates after preventive treatment with PGA sheets were 5.7% (95% CI: 3.6%-8.8%) and 20.6% (95% CI: 14.5%-28.4%), respectively.

CONCLUSION

The utilization of PGA sheets after ESD has an excellent outcome in reducing the risk of postoperative gastrointestinal bleeding and esophageal stricture.

Acellular Dermal Matrix Prevents Esophageal Stricture After Full Circumferential Endoscopic Submucosal Dissection in a Porcine Model

Esophageal stricture is a common complication after endoscopic submucosal dissection (ESD), especially in full circumferential ESD. This study investigated fully covered self-expanding metal stent (FCSEMS) placement with an acellular dermal matrix (ADM) for preventing post-ESD esophageal stricture. Twelve Bama minipigs were randomly divided into two groups, which underwent full circumferential ESD in the distal esophagus. In group A, an FCSEMS with ADM was placed at the mucosal defect, whereas group B underwent standard FCSEMS placement. The stent was removed during gastroscopy 2 weeks after the ESD procedure. At the fourth week, gastroscopy was repeated to evaluate local healing and stenosis. The animals were sacrificed, esophageal specimens were obtained for macroscopic and histological evaluation, and serum C-reactive protein (CRP) levels were quantified. Four weeks post ESD, dysphagia occurrence was lesser in group A than in group B. Group A demonstrated lesser esophageal stricture on macroscopic evaluation (21.02 ± 16.65% vs. 57.41 ± 8.48%, p = 0.001) in the form of enhanced re-epithelization (99.13 ± 0.98% vs. 96.63 ± 1.64%, p = 0.009), diminished submucosal fibrosis (1117.53 ± 188.83 um vs. 1834.69 ± 421.99 um, p = 0.003), and attenuated inflammatory infiltration (121.00 ± 30.66 vs. 188.17 ± 64.92, p = 0.045). The increase in the serum CRP level was lower in group A than in group B at 4 weeks post-ESD. FCSEMS combined with ADM can enhance re-epithelization in the process of wound healing and significantly reduce the degree of esophageal stenosis after circumferential ESD. This study provided important preclinical findings for subsequent clinical trials.

Futuristic Developments and Applications in Endoluminal Stenting

Endoscopic stenting is a well-established option for the treatment of malignant obstruction, temporary management of benign strictures, and sealing transmural defects, as well as drainage of pancreatic fluid collections and biliary obstruction. In recent years, in addition to expansion in indications for endoscopic stenting, considerable strides have been made in stent technology, and several types of devices with advanced designs and materials are continuously being developed. In this review, we discuss the important developments in stent designs and novel indications for endoluminal and transluminal stenting. Our discussion specifically focuses on (i) biodegradable as well as (ii) irradiating and drug-eluting stents for esophageal, gastroduodenal, biliary, and colonic indications, (iii) endoscopic stenting in inflammatory bowel disease, and (iv) lumen-apposing metal stent.

Recent Advances of Biomedical Materials for Prevention of Post-ESD Esophageal Stricture

Esophageal stricture commonly occurs in patients that have suffered from endoscopic submucosal dissection (ESD), and it makes swallowing difficult for patients, significantly reducing their life qualities. So far, the prevention strategies applied in clinical practice for post-ESD esophageal stricture usually bring various inevitable complications, which drastically counteract their effectiveness. Nowadays, with the widespread investigation and application of biomedical materials, lots of novel approaches have been devised in terms of the prevention of esophageal stricture. Biomedical polymers and biomedical-derived materials are the most used biomedical materials to prevent esophageal stricture after ESD. Both of biomedical polymers and biomedical-derived materials possess great physicochemical properties such as biocompatibility and biodegradability. Moreover, some biomedical polymers can be used as scaffolds to promote cell growth, and biomedical-derived materials have biological functions similar to natural organisms, so they are important in tissue engineering. In this review, we have summarized the current approaches for preventing esophageal stricture and put emphasis on the discussion of the roles biomedical polymers and biomedical-derived materials acted in esophageal stricture prevention. Meanwhile, we proposed several potential methods that may be highly rational and feasible in esophageal stricture prevention based on other researches associated with biomedical materials. This review is expected to offer a significant inspiration from biomedical materials to explore more effective, safer, and more economical strategies to manage post-ESD esophageal stricture.

Stent placement to prevent strictures after esophageal endoscopic submucosal dissection: a systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) is an important method for the treatment of early esophageal cancer. However, post-procedure stenosis is one of the most common long-term complications. This meta-analysis aimed to investigate whether stent placement is effective in the stenosis prevention, and which type of stent would be more effective. A systematic and electronic search of clinical trials and observational studies conducted before March 2020 on the efficacy of stent placement in preventing esophageal stricture after ESD was performed. Search terms included "ESD," "esophageal stenosis," "esophageal stricture," and "stents." We conducted a bias risk assessment of the eligible reports and a meta-analysis of the data using Revman 5.3 software. We included two randomized controlled trials (RCTs) and a prospective cohort study involving 163 patients with esophageal mucosal defects encompassing at least three-quarters of the esophagus circumference after ESD. The meta-analysis results showed that post-ESD stenosis rates (RR, 0.37; 95% CI, 0.22-0.64; P = 0.0003) and the number of endoscopic balloon dilations (EBDs) (MD, -1.74; 95% CI, -2.46 to -1.01; P < 0.00001) were reduced in the pooled analysis of three studies, indicating that stent placement was effective for stenosis prevention, especially a polyglycolic acid (PGA) sheet combined with stent placement can prevent stenosis (RR, 0.41; 95% CI, 0.23-0.74; P = 0.003) and reduce the number of EBDs (MD, -1.65; 95% CI, -2.40 to -0.90; P < 0.0001) significantly. Stent placement can reduce the rate of esophageal stenosis after ESD, especially when stents are covered with PGA sheets. However, more high-quality, low-bias RCTs with a sufficient sample size are needed to demonstrate its effectiveness.

Autologous esophageal mucosa with polyglycolic acid transplantation and temporary stent implantation can prevent stenosis after circumferential endoscopic submucosal dissection

Background

This research aimed at investigating the safety and efficacy of autologous esophageal mucosa (AEM) with polyglycolic acid (PGA) transplantation and temporary stent implantation (TSI) in preventing esophageal stenosis (ES) after early esophageal cancer (EC) surgery.

Methods

Between April 2019 and October 2020, patients scheduled for circumferential endoscopic submucosal dissection (ESD) were prospectively recruited. After ESD, autologous esophageal mucosal patches (MPs) were constructed on the absorbable PGA felt. Then, the felt was structured onto a covered metal mesh stent (CMMS) and attached to the ulcer surface. The stents were removed 6-8 weeks after the operation. The occurrence of ES and adverse events was observed and analyzed.

Results

Data from 25 patients were analyzed. In total, 14 patients (56%) had no stenosis during an average follow-up of 10.2 months, and 11 patients (44%) suffered strictures at a mean interval of 63.73 days after the ESD procedure. Stent migration occurred in 2 patients. No other complications, including perforations, bleeding, or wound infections, occurred. The median of endoscopic balloon dilatation (EBD) sessions was 2.16 (range, 0-14). There showed a higher post-ESD stricture rate in patients with lesions located in the middle-lower esophagus (P<0.05). More transplanted MPs may reduce the occurrence of ES.

Conclusions

AEM with PGA transplantation and TSI is a safe and effective approach of preventing ES and improving the life quality after circumferential ESD.

Efficacy of oral steroid gel in preventing esophageal stricture after extensive endoscopic submucosal dissection: a randomized controlled trial

BACKGROUND AND AIMS

Esophageal stricture is a distressing issue for patients with early esophageal cancer following extensive endoscopic submucosal dissection (ESD), and the current steroid-based approaches are unsatisfactory for stricture prophylaxis. We evaluated the efficacy of oral hydrocortisone sodium succinate and aluminum phosphate gel (OHA) for stricture prophylaxis after extensive ESD.

METHODS

Patients undergoing > 3/4 circumferential ESD were randomized to either the endoscopic loco-regional triamcinolone acetonide injection (ETI) plus oral prednisone group or the OHA group. The primary endpoint was incidence of esophageal stricture, and the secondary endpoints included adverse events (AEs) and endoscopic balloon dilations (EBDs).

RESULTS

The incidence of esophageal stricture in OHA group (per-protocol analysis, 9.4%, 3/32; intention-to-treat analysis, 12.1%, 4/33) was significantly less than that of control group (per-protocol analysis, 35.5%, 11/31, P = 0.013; intention-to-treat analysis, 39.4%, 13/33, P = 0.011). Two sessions of EBD were necessary to release all strictures in the OHA group, while the similar EBDs (median 2, range 1-4) for 11 of the control. Operation-related AEs included infection (control vs. OHA group = 9.7% vs. 31.3%, P = 0.034), operation-related hypokalemia (19.4% vs. 31.3%, P = 0.278), perforation (3.2% vs. 3.1%), post-ESD hemorrhage (6.5% vs. 0%), and cardiac arrhythmia (0% vs. 6.3%). Steroid-related AEs included steroid-related hypokalemia (16.1% vs. 25%) and bone fracture (3.2% vs. 0%). Multivariate logistic regression analysis demonstrated that OHA was an independent protective factor for stricture (OR 0.079; 95%CI 0.011, 0.544; P = 0.01) and mucosal defect > 11/12 circumference was an independent risk factor (OR 49.91; 95%CI 6.7, 371.83; P < 0.001).

CONCLUSIONS

OHA showed significantly better efficacy in preventing esophageal stricture after > 3/4 circumferential ESD compared to ETI plus oral prednisone.

Prevention of Stricture after Endoscopic Submucosal Dissection for Superficial Esophageal Cancer: A Review of the Literature

Endoscopic resection has been the standard treatment for intramucosal esophageal cancers (ECs) because of the low risk of lymph node metastases in the lesions. In recent years, endoscopic submucosal dissection (ESD), which can resect large ECs, has been performed. However, the risk of esophageal stricture after ESD is high when the mucosal defect caused by the treatment exceeds 3/4 of the circumference of the lumen. Despite the subsequent high risk of luminal stricture, ESD has been performed even in cases of circumferential EC. In such cases, it is necessary to take measures to prevent stricture. Therefore, in this review, we aimed to clarify the current status of stricture prevention methods after esophageal ESD based on previous literature. Although various prophylactic methods have been reported to have stricture-preventing effects, steroid injection therapy and oral steroid administration are mainstream. However, in cases of circumferential EC, both steroid injection therapy and oral steroid administration cannot effectively prevent luminal stricture. To solve this issue, clinical applications, such as tissue shielding methods with polyglycolic acid sheet, autologous oral mucosal epithelial sheet transplantation, and stent placement, have been developed. However, effective prophylaxis of post-ESD mucosal defects of the esophagus is still unclear. Therefore, further studies in this research field are needed.

Focus on patients with early esophageal cancer-a prognostic nomogram

Background

Esophageal cancer is a common cancer of the digestive system, with high morbidity and poor prognosis. However, while the prognosis of early esophageal cancer is relatively good, there is no effective model to accurately predict the prognosis of early esophageal cancer. The Aims of this study are to explore risk factors for the prognosis of early esophageal cancer and to establish a prediction nomogram for patients.

Methods

Surveillance, Epidemiology and End Results (SEER) Stat 8.3.5 was used to collect 2,351 cases of early esophageal cancer from 2004 to 2015 in the SEER database. Early esophageal cancer is defined as a lesion that is confined to the lamina propria and the muscularis mucosa. Prognostic factors were analyzed with the log-rank method and a Cox proportional hazard model by SPSS (v25.0). Independent prognostic factors were used to construct a nomogram with a Cox proportional hazard model. The C-index was used to evaluate the prediction effect of the nomogram. The internal validity of the nomogram was tested by discrimination and calibration using a bootstrap method with 1,000 resamplings.

Results

The median survival time was 30 months, and the 1-, 3-, and 5-year survival rates were 65.2%, 46.8%, and 41.6%, respectively. The male to female ratio was 3:1, and 85.33% of all patients were white. Univariate analysis showed that risk factors affecting patient prognosis included age (χ²=430.631, P<0.001), sex (χ²=48.1, P<0.001), marital status (χ²=107.597, P<0.001), race (χ²=58.928, P<0.001), primary site (χ²=98.675, P<0.001), tumor grade (χ²=116.421, P<0.001), surgery (χ²=1,259.33, P<0.001) and histologic type (χ²=231.062, P<0.001). Using multivariate analysis, we found that age (HR=1.787, 95% CI: 1.58–2.03), marital status (HR=0.774, 95% CI: 0.69–0.87), tumor grade (HR=1.241, 95% CI: 1.14–135), and surgery (HR=0.356, 95% CI: 0.33–0.39) were independent prognostic factors for patients with early esophageal cancer. We constructed the nomogram with the above independent factors, and the C-index value was 0.788.

Conclusions

This study obtained the latest epidemiological information on early esophageal cancer and determined that age, marital status, tumor grade and surgery were independent prognostic factors for early esophageal cancer. The nomogram developed with these factors could provide good prognosis prediction.

Advances in the Prevention and Treatment of Esophageal Stricture after Endoscopic Submucosal Dissection of Early Esophageal Cancer

Endoscopic submucosal dissection (ESD) has become the main treatment for early esophageal cancer. While treating the disease, ESD may also cause postoperative esophageal stricture, which is a global issue that needs resolution. Various methods have been applied to resolve the problem, such as mechanical dilatation, glucocorticoids, anti-scarring drugs, and regenerative medicine; however, no standard treatment regimen exists. This article describes and evaluates the strengths and limitations of new and promising potential strategies for the treatment and prevention of esophageal strictures.

Effectiveness of fibrin sealant as a hemostatic technique in accelerating endoscopic submucosal dissection-induced ulcer healing and preventing stricture in the esophagus: A retrospective study

The aim of the present retrospective study was to evaluate the effectiveness of conservative electrocoagulation followed by porcine fibrin sealant (FS) as a protective hemostatic technique for wounded microvessels in promoting the healing of endoscopic submucosal dissection (ESD)-induced ulcer, and preventing esophageal strictures that follow ESD. A total of 203 patients with early esophageal cancer or precancerous lesions were retrospectively analyzed. The 1-month ulcer healing and stricture rates were compared between the two groups (combined hemostats and electrocautery groups). The 1-month complete healing rate was 77.0% in the combined hemostats group and 52.6% in the electrocautery group (P=0.003). The use of FS and a smaller resected range (<3/4 circumference) was associated with a better 1-month healing rate. For patients with a ≥3/4 circumference mucosal defect, the esophageal stricture rate was 31.6% (6/19) in the combined hemostats group and 25.0% (2/8) in the electrocautery group. There was no difference in the stricture rate (P=0.737) and dilation time (P=0.733) between the two groups. In conclusion, the application of conservative electrocoagulation followed by porcine FS as a wound-protection technique promoted ESD-induced ulcer healing in the esophagus. However, this combined hemostatic technique was not superior to the conventional hemostatic method in preventing post-ESD stricture in patients with large esophageal mucosal defects.

Strategies to prevent stricture after esophageal endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) has been widely applied as a less invasive and more effective method for treating early esophageal cancers such as squamous cell carcinoma and dysplasia of Barrett's esophagus. However, post-ESD esophageal stricture often occurs if patients suffer circumferential mucosal defects of more than three-quarters of the circumference of the esophagus, which makes it difficult for patients to swallow and greatly reduces their quality of life. Moreover, there is currently no standard method to treat post-ESD esophageal stricture, even though it is extraordinarily important to prevent its formation. In recent years, several strategies to prevent esophageal stricture have emerged. These strategies can be classified into pharmacological, mechanical, tissue engineering, and other novel strategies, with each strategy having its own strengths and weaknesses. Although the pharmacological prophylaxis and mechanical strategies are relatively mature, they still have their drawbacks like high time-consumption, the occurrence of re-stricture, and significant side effects. Tissue engineering strategies and other novel strategies have shown promising preliminary results, but more clinical trials are needed. In this review, we discuss these strategies, with a particular focus on tissue engineering strategies and other novel strategies. It is hoped that this discussion will aid in finding more effective and safer strategies to prevent esophageal stricture.

Management of adverse events related to endoscopic resection of upper gastrointestinal neoplasms: Review of the literature and recommendations from experts

Prevention therapy is recommended for lesions >1/2 of the esophageal circumference. Locoregional steroid injection is recommended for lesions >1/2-3/4 of the esophageal circumference and oral steroids are recommended for lesions >1/2 of the subtotal circumference. For lesions of the entire circumference, oral steroid combined with injection steroid is considered. Endoscopic balloon dilatation (EBD) is the first choice of treatment for stricture after esophageal endoscopic submucosal dissection (ESD). Radical incision and cutting or self-expandable metallic stent can be considered for refractory stricture after EBD. In case of intraoperative perforation during esophageal ESD, endoscopic clip closure should be initially attempted. Surgery is considered for treatment of delayed perforation. Current standard practice for prevention of delayed bleeding after gastric ESD includes prophylactic coagulation of vessels on post-ESD ulcers and giving proton pump inhibitors. Chronic kidney disease stage 4 or 5, multiple antithrombotic drug use, anticoagulant use, and heparin bridging therapy are high-risk factors for delayed bleeding after gastric ESD. Intraoperative perforation during gastric ESD is initially managed by endoscopic clip closure. If endoscopic clip closure is difficult, other methods such as over-the-scope clip (OTSC), polyglycolic acid (PGA) sheet shielding etc. are attempted. Delayed perforation usually requires surgical intervention, but endoscopic closure by OTSC or PGA sheet may be considered. Resection of three-quarters of the circumference is a risk factor for stenosis after gastric ESD. Giving prophylactic local steroid injection and/or oral steroid is reported, but effectiveness has not been fully verified as has been done for esophageal stricture. The main management method for gastric stenosis is EBD but it may cause perforation.

Cyclodextrin Polymer Preserves Sirolimus Activity and Local Persistence for Antifibrotic Delivery over the Time Course of Wound Healing

Fibrosis and dysphagic stricture of the esophagus is a major unaddressed problem often accompanying endoscopic removal of esophageal cancers and precancerous lesions. While weekly injections of antiproliferative agents show potential for improved healing, repeated injections are unlikely clinically and may alternatively be replaced by creating an esophageal drug delivery system. Affinity-based polymers have previously shown success for continuous delivery of small molecules for weeks to months. Herein, we explored the potential of an affinity-based microparticle to provide long-term release of an antiproliferative drug, sirolimus. In molecular docking simulations and surface plasmon resonance experiments, sirolimus was found to have suitable affinity for beta-cyclodextrin, while dextran, as a low affinity control, was validated. Polymerized beta-cyclodextrin microparticles exhibited 30 consecutive days of delivery of sirolimus during in vitro release studies. In total, the polymerized beta-cyclodextrin microparticles released 36.9 mg of sirolimus per milligram of polymer after one month of incubation in vitro. Taking daily drug release aliquots and applying them to PT-K75 porcine mucosal fibroblasts, we observed that cyclodextrin microparticle delivery preserved bioactivity of sirolimus inhibiting proliferation by 27-67% and migration of fibroblasts by 28-100% of buffer treated controls in vitro. Testing for esophageal injection site losses, no significant loss was incurred under simulated saliva flow for 10 min, and 16.7% of fluorescently labeled polymerized cyclodextrin microparticle signal was retained at 28 days after submucosal injection in esophageal tissue ex vivo versus only 4% of the initial amount remaining for free dye molecules injected alone. By combining affinity-based drug delivery for continuous long-term release with a microparticle platform that is injectable yet remains localized in tissue interstitium, this combination platform demonstrates promise for preventing esophageal fibrosis and stricture.

Efficacy of triamcinolone-soaked polyglycolic acid sheet plus fully covered metal stent for preventing stricture formation after large esophageal endoscopic submucosal dissection

Esophageal stricture is a major problem for patients with large superficial esophageal squamous cell neoplasms (SESCNs) after endoscopic submucosal dissection (ESD). Although many measures could be used as prophylaxis for post-ESD strictures, a well-accepted method has not yet been established. We propose using a triamcinolone-soaked polyglycolic acid sheet plus fully covered metal stent (TS-PGA+FCMS) as a novel method to prevent stricture formation after large esophageal ESD. From June 2016 to May 2017, nine patients with SESCNs (≥3/4 of the esophageal circumference) who underwent TS-PGA+FCMS placement immediately after ESD and did not require additional surgical resection were enrolled in this case series. All stents were removed 4-6 weeks post-ESD. The sizes of mucosal defects in 9 patients were 3/4 (n = 1), 4/5 (n = 2), 1/1 (n = 6). The average size of resection was 90.0 mm (range: 60-140 mm). The incidence of stricture was 33.3% (3/9) of patients. No stricture occurred in 3 patients with noncircumferential resection, while stricture occurred in 50% (3/6) patients with circumferential resection. The median number of EBD sessions was 4 (range: 3-4 sessions). No adverse events or recurrences were observed during the median follow-up period of 15.2 months (range: 12-22 months). The TS-PGA+FCMS method is safe and may decrease the incidence of esophageal stricture and the number of EBD sessions after large esophageal ESD.