Outcomes of endoscopic submucosal dissection for gastroesophageal reflux disease (ESD-G) for medication-refractory gastroesophageal reflux disease: 35 cases underwent ESD-G including 15 cases followed more than 5 years

Long-term efficacy of antireflux mucosectomy in patients with refractory gastroesophageal reflux disease

OBJECTIVES

Minimally invasive treatments have been applied for gastroesophageal reflux disease (GERD), but the long-term results are controversial. Antireflux mucosectomy (ARMS) is a simple endoscopic procedure that does not require the insertion of a foreign body. We provide the first report on the long-term results of ARMS.

METHODS

This was a single-center, single-arm trial, prospective study of 88 patients with proton pump inhibitor (PPI)-refractory GERD who underwent ARMS between June 2012 and June 2017. Primary outcomes were the rates of long-term effectiveness and PPI discontinuation. Secondary outcomes were to compare patients' preoperative background characteristics, questionnaire, and multichannel intraluminal impedance and pH monitoring data to examine the predictive factors of ARMS. The clinical course was reviewed, including the need for additional treatment after ARMS.

RESULTS

Antireflux mucosectomy produced a long-term effect in 68.3% of the patients, and PPI could be discontinued in 42% of patients. There were significant differences in age, intensity of preoperative symptoms, and acid-related indicators. Forty-five percent (27/60) had reflux hypersensitivity and ARMS provided long-term effectiveness in 81% of these patients. There was no significant difference in subjective symptom assessment between those with short-term and long-term efficacy. Additional treatment was administered in 23% (14/60) and scheduled at 1-2 years' follow-up.

CONCLUSIONS

Antireflux mucosectomy showed long-term efficacy, and many of the cases with short-term effects were able to maintain them. In addition, ARMS is also effective in patients with reflux hypersensitivity, and provides a treatment option that bridges the gap between surgical and medical treatment.

Gastroesophageal Reflux Disease: Pathophysiology and New Treatment Trends

Gastroesophageal reflux disease (GERD) is caused by the reflux of gastric contents into the esophagus due to a decline in esophageal clearance and anti-reflux barrier mechanisms. Mucosal injury is caused by a combination of gastric juice directly damaging the esophageal mucosa and the immune and inflammatory mechanism in which inflammatory cytokines released from the esophageal mucosal epithelium cause neutrophil migration, triggering inflammation. Gastric secretion inhibitors are the first-line treatment for GERD, but they can be combined with prokinetic agents and Chinese herbal remedies. However, pharmacotherapy cannot improve anatomical problems or prevent physical causes of GERD, such as reflux of non-acidic contents. Therefore, surgery can be warranted, depending on the pathology. Intraluminal endoscopic therapy, which is both less invasive and more effective than surgery, was recently developed and applied in Europe and the United States. In Japan, intraluminal endoscopic therapies, such as anti-reflux mucosectomy, anti-reflux mucosal ablation, and endoscopic submucosal dissection, for GERD have been independently developed.

Role of endoscopy in gastroesophageal reflux disease

In general, gastroesophageal reflux disease (GERD) is diagnosed clinically based on typical symptoms and/or response to proton pump inhibitor treatment. Upper gastrointestinal endoscopy is reserved for patients presenting with alarm symptoms, such as dysphagia, odynophagia, significant weight loss, gastrointestinal bleeding, or anorexia; those who meet the criteria for Barrett's esophagus screening; those who report a lack or partial response to proton pump inhibitor treatment; and those with prior endoscopic or surgical anti-reflux interventions. Newer endoscopic techniques are primarily used to increase diagnostic yield and provide an alternative to medical or surgical treatment for GERD. The available endoscopic modalities for the diagnosis of GERD include conventional endoscopy with white-light imaging, high-resolution and high-magnification endoscopy, chromoendoscopy, image-enhanced endoscopy (narrow-band imaging, I- SCAN, flexible spectral imaging color enhancement, blue laser imaging, and linked color imaging), and confocal laser endomicroscopy. Endoscopic techniques for treating GERD include esophageal radiofrequency energy delivery/Stretta procedure, transoral incisionless fundoplication, and endoscopic full-thickness plication. Other novel techniques include anti-reflux mucosectomy, peroral endoscopic cardiac constriction, endoscopic submucosal dissection, and endoscopic band ligation. Currently, many of the new endoscopic techniques are not widely available, and their use is limited to centers of excellence.

Frontiers in Endoscopic Treatment for Gastroesophageal Reflux Disease

BACKGROUND

The 3rd edition of the evidence-based clinical practice guidelines for gastroesophageal reflux disease (GERD) 2021 from the Japanese Society of Gastroenterology states that the treatment strategy for potassium-competitive acid blocker (PCAB)-refractory GERD remains unclear. Furthermore, even if GERD improves with the administration of an acid secretion inhibitor, it is feared that GERD may flare up after discontinuation of the drug, resulting in some cases in which patients are forced to take vonoprazan semipermanently (the so-called PCAB-dependent cases). From a global perspective, PCAB is not yet used in all countries and regions, and measures that can be taken now for cases in which a conventional proton pump inhibitor (PPI) is inadequately effective need to be devised.

SUMMARY

Endoscopic treatment for GERD may be effective in cases where conventional proton pump inhibitors are ineffective; however, there are insufficient long-term studies to corroborate this, and its cost effectiveness is unknown. Other treatment options for PCAB or PPI-refractory GERD include surgical procedures (Nissen and Toupet operations), which have a longer history than endoscopic treatment for GERD. However, their long-term results are not as good as those of acid secretion inhibitors, and they are not cost effective. Endoscopic treatment for GERD may fill gaps in inadequate surgical treatment. In April 2022, endoscopic anti-reflux mucosal resections (ARMS [anti-reflux mucosectomy] and ESD-G [endoscopic submucosal dissection for GERD]) were approved for reimbursement, making endoscopic treatment of GERD possible throughout Japan.

KEY MESSAGES

It is important to identify the background factors in cases in which endoscopic treatments are effective.

Comparative Evaluations on Real-Time Monitoring of Temperature Sensors during Endoscopic Laser Application

Temperature sensors, such as Fiber Bragg Grating (FBG) and thermocouple (TC), have been widely used for monitoring the interstitial tissue temperature during laser irradiation. The aim of the current study was to compare the performance of both FBG and TC in real-time temperature monitoring during endoscopic and circumferential laser treatment on tubular tissue structure. A 600-µm core-diameter diffusing applicator was employed to deliver 980-nm laser light (30 W for 90 s) circumferentially for quantitative evaluation. The tip of the TC was covered with a white tube (W-TC) in order to prevent direct light absorption and to minimize temperature overestimation. The temperature measurements in air demonstrated that the measurement difference in the temperature elevations was around 3.5 °C between FBG and W-TC. Ex vivo porcine liver tests confirmed that the measurement difference became lower (less than 1 °C). Ex vivo porcine esophageal tissue using a balloon-integrated catheter exhibited that both FBG and W-TC consistently showed a comparable trend of temperature measurements during laser irradiation (~2 °C). The current study demonstrated that the white tube-covered TC could be a feasible sensor to monitor interstitial tissue temperature with minimal overestimation during endoscopic laser irradiation. Further in vivo studies on gastroesophageal reflux disease will investigate the performance of the W-TC to monitor the temperature of the esophageal mucosa surface in real-time mode to warrant the safety of endoscopic laser treatment.

In Vitro and In Vivo Investigation on the Effectiveness of Alginate-Based Gastric Mucosal Protective Gel

Objective

To investigate the feasibility and effectiveness of an alginate-based gastric mucosal protective gel on the gastric ulcer.

Methods

(1) In the physical protection model, after GES-1 cell attachment add the gel to transwell chamber, add different concentrations of HCl to the gel. Absorbance was measured to assess proliferation and images of the cells migrating into the wound were taken; then the migration rate of the cells was quantified by comparing images. (2) In the gastric ulcer model, excise the gastric mucosal of SD rats; the gel and fixative were applied on the artificial ulcer immediately. Dissect rats after 10 days, and calculate the wound healing rate and analyzed histology changes.

Results

The effect of hydrochloric acid on cells in the lower layer was significantly reduced after the use of gastric mucosal protection gel. The protective gel had an isolation effect on different concentrations of acid. A number of GES-1 were significantly higher than those in the control group at 24 h to 72 h (P < 0.01). The migration was observed compared with the control group. The average healing rate of ulcer in the gel group was about 50%, and the control group was about 30%. Inflammation occurred in all wound regions after ten days. In the gel group, inflammatory infiltration depth was lower than that of the control, and part of SD rats' new muscle layer appeared without inflammatory infiltration. The connective tissue proliferation promoted tissue repair. In the control group, necrosis marginal, mucosal hyperplasia, marginal lymphocyte aggregation, and bleeding were observed.

Conclusion

This novel gel mainly has an isolating and shielding effect to prevent the wound from being exposed to gastric acid for a long time, and it can reduce the inflammatory reaction on the wounds to promote the healing of the ulcer. The gastric mucosal protective gel cannot only promote the speed of wound healing but also improve the quality of wound healing.