Recent developments in pathogenesis, diagnosis and therapy of Barrett's esophagus

The burden of illness from esophageal adenocarcinoma continues to rise in the Western world, and overall prognosis is poor. Given that Barrett’s esophagus (BE), a metaplastic change in the esophageal lining is a known cancer precursor, an opportunity to decrease disease development by screening and surveillance might exist. This review examines recent updates in the pathogenesis of BE and comprehensively discusses known risk factors. Diagnostic definitions and challenges are outlined, coupled with an in-depth review of management. Current challenges and potential solutions related to screening and surveillance are discussed. The effectiveness of currently available endoscopic treatment techniques, particularly with regards to recurrence following successful endotherapy and potential chemopreventative agents are also highlighted. The field of BE is rapidly evolving and improved understanding of pathophysiology, combined with emerging methods for screening and surveillance offer hope for future disease burden reduction.

Advanced Imaging in Barrett's Esophagus

Barrett's esophagus (BE) is present in up to 5.6% of the US population and is the precursor lesion for esophageal adenocarcinoma. Surveillance endoscopy is the primary management approach for BE. However, standard protocol biopsies have been associated with significant miss rates of dysplastic lesions in patients with BE. Thus, a variety of methods to optimize the imaging of BE have been developed to improve the efficiency and diagnostic yield of surveillance endoscopy in detecting early neoplasia. These techniques use changes that occur at macroscopic, microscopic, and subcellular levels in early neoplasia and are the focus of this article.

Endoscopic prediction of tumor margin and invasive depth in early gastric cancer

Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related deaths in the world. The prognosis of GC is clearly associated with the tumor stage, with a 5-year overall survival rate for early gastric cancer (EGC) exceeding 90%, which is significantly higher than that of advanced gastric cancer. Endoscopic resection, including endoscopic mucosal resection and endoscopic submucosal dissection, has been adopted in recent decades as the first treatment option of EGC in many countries for its minimal invasion and high curative rate. However, the horizontal and vertical margins are related to the curative resection of EGC and the prognosis of patients. Thus the accurate prediction of the tumor boundary and its invasive depth before treatment counts for much in planning the most appropriate treatment strategy and promising curative resection. To date, various endoscopic techniques have been identified to play a role in pretreatment evaluation, such as white light endoscopy, chromoendoscopy, narrow band imaging and endoscopic ultrasonography. This article aimed to summarize the diagnostic methods, applications and limitations of these different endoscopic techniques for identifying tumor horizontal and vertical margins in EGC, helping to increase preoperative evaluation of capabilities and to improve the curative resection rate of EGC.

Treatment of gastrointestinal sphincters spasms with botulinum toxin A

Botulinum toxin A inhibits neuromuscular transmission. It has become a drug with many indications. The range of clinical applications has grown to encompass several neurological and non-neurological conditions. One of the most recent achievements in the field is the observation that botulinum toxin A provides benefit in diseases of the gastrointestinal tract. Although toxin blocks cholinergic nerve endings in the autonomic nervous system, it has also been shown that it does not block non-adrenergic non-cholinergic responses mediated by nitric oxide. This has promoted further interest in using botulinum toxin A as a treatment for overactive smooth muscles and sphincters. The introduction of this therapy has made the treatment of several clinical conditions easier, in the outpatient setting, at a lower cost and without permanent complications. This review presents current data on the use of botulinum toxin A in the treatment of pathological conditions of the gastrointestinal tract.

The comparison of saline enema and bisacodyl in rectal preparation before anorectal surgery

BACKGROUND

Given the limited data on the need of mechanical bowel preparation application before anorectal surgeries and the preferred method for bowel preparation, we aimed to compare saline enema and bisacodyl in rectal preparation before anorectal surgery.

MATERIALS AND METHODS

This is a randomized clinical trial study. Seventy-nine hospitalized patients for anorectal surgery (hemorrhoid, fissure, and fistula) were recruited by convenient sampling and then randomly allocated to receive 500 cc Saline by rectal enema or six bisacodyl tablets (Sobhan company) beginning from a day before the operation in order to prepare the bowel. After surgery, surgeons' satisfaction of the surgery and patients' satisfaction of the preparation process were evaluated in the ward using Likert score by a nurse blind to the study. Also, the patients were interviewed for pain after the first defecation, using numeric rating scale based on a 0-10 scores. All patients were actively followed-up after discharge for 1 mo concerning postoperative complications. The obtained data were analyzed by SPSS software (version 16), Mann-Whitney, chi-squared, and Fisher exact tests at the significant level of P < 0/0.5.

RESULTS

A total of 79 patients participated in the study, 38 received 500-cc saline by rectal enema and 41 bisacodyl tablets. No significant differences were observed between the two groups in most variables except for pain after the first defecation (P = 0.032).

CONCLUSIONS

According to the results, the bisacodyl approach results in less pain in the first postoperative defecation and fewer complications than the rectal enema. Thus, bisacodyl can be suggested as a superior counterpart for enema.

Recent advancement of therapeutic endoscopy in the esophageal benign diseases

Over the past 30 years, the field of endoscopy has witnessed several advances. With the advent of endoscopic mucosal resection, removal of large mucosal lesions have become possible. Thereafter, endoscopic submucosal resection was refined, permitting en bloc removal of large superficial neoplasms. Such techniques have facilitated the development of antireflux mucosectomy, a promising novel treatment for gastroesophageal reflux. The introduction and use of over the scope clips has allowed for endoscopic closure of defects in the gastrointestinal tract, which were traditionally treated with surgical intervention. With the development of per-oral endoscopic myotomy (POEM), the treatment of achalasia and spastic disorders of the esophagus have been revolutionized. From the submucosal tunnelling technique developed for POEM, Per oral endoscopic tumor resection of subepithelial tumors was made possible. Simultaneously, advances in biotechnology have expanded esophageal stenting capabilities with the introduction of fully covered metal and plastic stents, as well as biodegradable stents. Once deemed a primarily diagnostic tool, endoscopy has quickly transcended to a minimally invasive intervention and therapeutic tool. These techniques are reviewed with regards to their application to benign disease of the esophagus.

Endoscopic resection of submucosal tumors

Submucosal gastrointestinal tumors represent a unique, diverse and challenging group of lesions found in modern medical practice. While management has traditionally been surgical, the development of advanced endoscopic techniques is challenging this approach. This review aims to investigate the role of endotherapy in treatment pathways, with a focus on carcinoid and gastrointestinal stromal tumors. In particular, we will discuss which lesions can be safely treated endoscopically, the evidence base behind such approaches and the limitations of the current evidence. The review will consider how these techniques may change the management of submucosal tumors in the future.

Helicobacter pylori Eradication on the Prevention of Metachronous Lesions after Endoscopic Resection of Gastric Neoplasm: A Meta-Analysis

Background

There is controversy about the effect of Helicobacter pylori (H. pylori) eradication on the prevention of metachronous gastric cancer after endoscopic resection (ER).

Aims

The aim of this study was to systematically evaluate the effect of H. pylori eradication on the prevention of metachronous gastric lesions after ER of gastric neoplasms.

Methods

We performed a systematic search of PubMed, EMBASE, the Cochrane Library, and MEDLINE that encompassed studies through April 2014. Our meta-analysis consisted of 10 studies, which included 5881 patients who underwent ER of gastric neoplasms.

Results

When we compared the incidence of metachronous lesions between H. pylori-eradicated and non-eradicated groups, H. pylori eradication significantly lowered the risk of metachronous lesions after ER of gastric neoplasms (five studies, OR = 0.392, 95% CI 0.259 – 0.593, P < 0.001). When we compared H. pylori-eradicated and persistent groups, again, H. pylori eradication significantly lowered the incidence of metachronous lesions after ER of gastric neoplasms (six studies, OR = 0.468, 95% CI 0.326 – 0.673, P < 0.001). There was no obvious heterogeneity across the analyzed studies.

Conclusions

This meta-analysis suggests a preventive role for H. pylori eradication for metachronous gastric lesions after ER of gastric neoplasms. Thus, H. pylori eradication should be considered if H. pylori infection is confirmed during ER.

Application and Interpretation of High-resolution Manometry for Pharyngeal Dysphagia

The pharyngeal phase of swallowing is a complex event consisted with subsequent muscular contractions and pressure generation to move a bolus from the mouth to the esophagus. Recently, high-resolution impedance manometry (HRIM) was developed and used for the evaluation of pharyngeal dysphagia. Although HRIM provides precise pharyngeal pressure information, it has yet to be used as part of routine clinical practice for the assessment of dysphagia. The main reasons are thought to be that the test method and result interpretation are not easily applicable and standardized. The anatomical landmarks for HRIM parameters are velopharynx, tongue base, epiglottis, low pharynx, and upper esophageal sphincter. With HRIM, the pressure and timing data could be obtained at a precise anatomical structure. In the present review, we will review how to apply HRIM for the evaluation of pharyngeal dysphagia, including the interpretation of its parameters.

Current status of endoscopic ultrasound for the upper gastrointestinal tract in Asia

We summarize the current status of endoscopic ultrasound (EUS) for the upper gastrointestinal (GI) tract solely in Asia, focusing on the staging of superficial cancers and the diagnosis of submucosal tumors (SMT), by analysis of questionnaire responses and a literature review. EUS for assessing the depth of superficial cancers of the upper GI tract is useful; however, evidence is lacking to support that EUS is superior to other modalities. The current status of EUS varies across different Asian countries, and standardization of the methods used both during the procedure and for depth subclassification is necessary to evaluate the diagnostic accuracy. Although EUS alone is limited in the diagnosis of SMT, EUS-guided fine-needle aspiration is an effective and safe diagnostic tool. Although there is a role for EUS, there are still many limitations both technically and in terms of accessibility.

Endoscopic submucosal dissection in gastric lesions: the 100 cases experience from a tertiary reference center in West

OBJECTIVE

Endoscopic submucosal dissection (ESD) is an endoscopic treatment method widely used in premalignant and malignant lesions in countries of the Far East. This method, which is difficult technically and has a high complication risk rate, has rarely been performed in the West, because of the fewer number of upper gastrointestinal lesions. In the present study, we aimed to present our results of gastric ESD procedures in respect to the learning curve.

METHODS

A total of 100 ESD procedures, which were performed in the stomach between April 2012 and September 2014, were recorded prospectively before and after the procedure. Patient data were analyzed retrospectively. ESD procedures were numbered chronologically; the first 30 patients constituted group 1, whereas the rest were classified as the group 2. ESD results were compared between the groups.

RESULTS

In a total of 95 patients, 100 gastric ESDs were performed. The overall en-bloc and complete resection rates were 93% and 92%, respectively. In respect of the learning curve, there were significant differences in the sizes of lesions and tissues obtained, procedure duration and dissection rate, snare use and knife preferences between groups (p = 0.002, p < 0.001, p = 0.003, p < 0.001, p = 0.009, and p < 0.001, respectively). No significant difference was detected in the en-bloc and complete resection rates and complications between the groups.

CONCLUSION

According to guideline recommendations and masters for ESD, if ESD training is initiated and continued, successful ESD may be performed in localized lesions in the stomach.

[Peroral endoscopic myotomy for treatment of achalasia. Literature review and own initial experience]

Peroral endoscopic myotomy (POEM) is a new, purely endoscopic procedure for treatment of achalasia. Due to the lack of incisions POEM can be regarded as a true NOTES procedure. With POEM a myotomy is created in a similar fashion to the previous standard treatment, laparoscopic Heller myotomy (LHM). The relatively free choice of length and localization of the myotomy may be regarded as advantages of POEM. The procedure starts with a mucosal incision (mucosal entry) followed by preparation of a submucosal tunnel crossing the esophagogastric junction and creation of a myotomy in an antegrade direction before the mucosal access is closed with endoscopic clip placement. Since the first description of the application of POEM in humans in 2010 by the pioneer Haruhiro Inoue, Yokohama, Japan, it has been used increasingly and investigated in some centers in Asia, the U.S.A. and also Europe. The results are very promising. Although the procedure is technically demanding it can be performed safely with low complication rates. The POEM procedure achieves very good control of dysphagia and gastroesophageal reflux witch is only a rare side-effect witch is well-controllable with proton pump inhibitors (PPI). We review the currently available data from the literature and present our own initial series of  14 patients treated with POEM.

Gastric cancer cell proliferation is suppressed by frizzled-2 short hairpin RNA

In order to identify novel targets for the molecular therapy of gastric cancer (GC), we investigated the mRNA and protein expression of frizzled-2 (Fz2), a Wnt signaling pathway receptor. Reverse-transcriptase polymerase chain reaction (PCR) amplification was utilized to determine the expression patterns of Fz genes in normal stomach and in the GC cell lines MKN45 and MKN74. Immunostaining was performed on surgical specimens of GC using an antibody against Fz2. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2- (4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed on MKN45 cells and MKN74 cells transfected with Fz2 short-hairpin (sh) RNA. Cell motility was analyzed by scratch assay following Fz2 shRNA. Real-time quantitative PCR was performed to analyze the expression levels of cyclin D1 and matrix metallopeptidase 9 (MMP-9). Fz1, 3, 6 and 8 were expressed in normal stomach, and in MKN45 and MKN74 cells. Fz2 was expressed in normal stomach and in MKN45, but not in MKN74 cells. Well-differentiated GC tissue was weakly positive for Fz2 in cell membranes. Fz2 was positive in both the cell membrane and cytoplasm of GC tissues of moderately differentiated and poorly differentiated adenocarcinoma. Signet ring cells were positive for cytoplasmic Fz2. Proliferation of MKN45 and MKN74 cells was suppressed by Fz2 shRNA, and a scratch assay demonstrated that Fz2 shRNA suppressed also MKN45 and MKN74 cell motility. Furthermore, Fz2 shRNA application led to downregulated mRNA expression of both cyclin D1 and MMP-9. Fz2, 3, 6 and 8 were expressed in normal stomach, and in MKN45 and MKN74 GC cells. Fz2 shRNA suppressed cell proliferation and motility of MKN45 and MKN74 cells, and downregulated cyclin D1 and MMP-9 expression in these GC cell lines.

Efficacy of peroral endoscopic myotomy (POEM) in the treatment of achalasia: a systematic review and meta-analysis

BACKGROUND

Peroral endoscopic myotomy (POEM) is an evolving therapeutic modality for achalasia. We aim to determine efficacy of POEM for the treatment of achalasia and compare it with laparoscopic Heller's myotomy (LHM).

MATERIALS AND METHODS

Systematic review and meta-analyses was conducted on 19 studies using POEM for achalasia. Pubmed, Medline, Cochrane, and Ovid databases, were searched using the terms 'achalasia', 'POEM', 'peroral endoscopic myotomy', 'per oral endoscopic myotomy', and 'per-oral endoscopic myotomy'. Reduction in Eckhart's score and lower esophageal sphincter (LES) pressure were the main outcome measures.

RESULTS

A total of 1,045 patients underwent POEM in 29 studies. Ninety patients undergoing POEM was compared with 160 undergoing LHM in five studies. Nineteen and 14 studies, respectively, evaluated for Eckhart's score and LES pressure. There was significant reduction in Eckhart's score and LES pressure with effect sizes of -7.95 (p < 0.0001) and -7.28 (p < 0.0001), respectively. There was significant heterogeneity among the studies [(Q = 83.06; I (2) = 78.33 %; p < 0.0001) for Eckhart's score and (Q = 61.44; I (2) = 75.68 %; p < 0.0001) for LES pressure]. There were no differences between POEM and LHM in reduction in Eckhart's score, post-operative pain scores and analgesic requirements, length of hospital stay, adverse events, and symptomatic gastroesophageal reflux/reflux esophagitis. Operative time was significantly lower for POEM.

CONCLUSIONS

POEM is effective for achalasia and has similar outcomes as LHM. Multicenter randomized trials need to be conducted to further compare the efficacy and safety of POEM between treatment naïve achalasia patients and those who failed treatment.

Risk factors for local recurrence in patients with positive lateral resection margins after endoscopic submucosal dissection for early gastric cancer

BACKGROUND

With the widespread use of endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC), the number of cases with incomplete resection due to positive lateral resection margins (LM+) is increasing. Local recurrence, which occurs frequently in LM+ cases, is an important issue. This study aimed to clarify the clinicopathological factors related to tumor recurrence in LM+ cases after ESD for EGC.

METHODS

From January 2005 to December 2012, a total of 1,083 patients with EGC underwent ESD at our hospital. Of these, cases with a pathological diagnosis of LM+ were included in this study. Patients with positive vertical resection margins, those who underwent surgical resection immediately or were followed up for less than 6 months after ESD, were excluded.

RESULTS

A total of 55 LM+ cases after ESD for EGC were enrolled. Incorrect delineation of a lesion that extended pathologically beyond the ESD marking dots was the main cause of LM+. Local recurrence was found in 20 (36.4 %) patients (median follow-up period, 23 months). Local recurrence rates related to LM+ length were as follows: 7/29 (24.1 %) in 2 mm, 6/16 (37.5 %) in 4 mm, 1/3 (33.3 %) in 6 mm, 4/5 (80 %) in 8 mm, and 2/2 (100 %) in ≥ 10 mm. In multivariate analysis, tumor size > 2 cm (OR 4.48, 95 % CI 1.18-16.99, p = 0.027), and LM+ length > 6 mm (OR 7.65, 95 % CI 1.15-50.70, p = 0.035) were independent risk factors for tumor recurrence.

CONCLUSION

To decrease the risk of LM+, it is highly important to accurately delineate the lateral margins during ESD; when the final histopathological result is LM+, cases with LM+ length >6 mm or tumor size > 2 cm should be considered for additional surgical resection or re-ESD because of a high risk of tumor recurrence.

Clinical outcomes of early gastric cancer with lymphovascular invasion or positive vertical resection margin after endoscopic submucosal dissection

BACKGROUND

In early gastric cancer (EGC) cases with lymphovascular invasion or positive vertical margins after endoscopic submucosal dissection (ESD), additional radical gastrectomy is performed on principle. However, an additional surgery is often difficult to consider if the surgical approach itself is challenging or the patient refuses surgery. In such cases, only close surveillance is performed without additional surgical procedures. This study aimed to examine the difference in clinical prognosis of EGC cases with lymphovascular invasion or positive vertical margins after ESD either with or without surgery.

METHODS

We retrospectively studied 83 patients with lymphovascular invasion or positive vertical margins after ESD from July 2005 to November 2013.

RESULTS

Of the 83 patients, 45 (54.2%) underwent radical additional gastrectomy (surgical group) and 38 (45.8%) were under close surveillance without surgical or endoscopic treatments (close surveillance group.) The cancer-free survival period was 78.3 ± 3.4 months in the surgical group and 64.5 ± 4.6 months in the close surveillance group. The recurrence rates did not significantly differ between the 2 groups, at 7.9% in the surgical group and 6.7% in the non-surgical group.

CONCLUSIONS

Close surveillance may be suggested as an option for EGC patients for whom a surgical approach is difficult, who exhibit a positive vertical margin after ESD, and who have no lymphovascular or deep submucosa invasion after ESD.

International digestive endoscopy network 2014: turnpike to the future

Social networks are useful in the study of relationships between individuals or entire populations, and the ties through which any given social unit connects. Those represent the convergence of the various social contacts of that unit. Consequently, the term "social networking service" (SNS) became extremely familiar. Similar to familiar SNSs, International Digestive Endoscopy Network (IDEN) 2014 was based on an international network composed of an impressive 2-day scientific program dealing with a variety of topics for gastrointestinal (GI) diseases, which connects physicians and researchers from all over the world. The scientific programs included live endoscopic demonstrations and provided cutting-edge information and practice tips as well as the latest advances concerning upper GI, lower GI, and pancreatobiliary endoscopy. IDEN 2014 featured American Society for Gastrointestinal Endoscopy-Korean Society of Gastrointestinal Endoscopy (ASGE-KSGE)-joint sessions prepared through cooperation between ASGE and KSGE. Furthermore, IDEN 2014 provided a special program for young scientists called the 'Asian Young Endoscopist Award Forum' to foster networks, with many young endoscopists from Asian countries taking an active interest and participation.

Ever-changing endoscopic treatment for early gastric cancer: Yesterday-today-tomorrow

Endoscopic resection has been an optimal treatment for selected patients with early gastric cancer (EGC) based on advances in endoscopic instruments and techniques. As endoscopic submucosal dissection (ESD) has been widely used for treatment of EGC along with expanding ESD indication, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis (LNM). Recently, new techniques including ESD or endoscopic full-thickness resection combined with sentinel node navigation enable minimal tumor resection and a laparoscopic lymphadenectomy in cases of EGC with high risk of LNM. This review covers the development and challenges of endoscopic treatment for EGC. Moreover, a new microscopic imaging and endoscopic techniques for precise endoscopic diagnosis and minimally invasive treatment of EGC are introduced.

Peroral endoscopic myotomy: establishing a new program

Achalasia is an esophageal motility disorder characterized by incomplete relaxation of the lower esophageal sphincter (LES) and aperistalsis of the esophageal body. Treatment of achalasia is aimed at decreasing the resting pressure in the LES. Peroral endoscopic myotomy (POEM), derived from natural orifice transluminal endoscopic surgery (NOTES) and advances in endoscopic submucosal dissection (ESD), presents a novel, minimally invasive, and curative endoscopic treatment for achalasia. POEM involves an esophageal mucosal incision followed by creation of a submucosal tunnel crossing the esophagogastric junction and myotomy before closure of the mucosal incision. Although the procedure is technically demanding and requires a certain degree of skill and competency, treatment success is high (90%) with low complication rates. Since the first described POEM in humans in 2010, it has been used increasingly at centers worldwide. This article reviews available published clinical studies demonstrating POEM efficacy and safety in order to present a proposal on how to establish a dedicated POEM program and reach base proficiency for the procedure.

Effect of peroral endoscopic myotomy in achalasia patients with failure of prior pneumatic dilation: a prospective case-control study

BACKGROUND AND AIM

To investigate the effectiveness of peroral endoscopic myotomy (POEM) surgery in achalasia patients with failure of prior pneumatic dilation (PD).

METHODS

Twenty-one patients with a history of failed PD were prospectively recruited as the case group, and 30 patients with no history of prior treatment for achalasia were included as the control group. Outcome of POEM procedures was evaluated through esophageal manometry, timed barium esophagogram and short form 36 (SF-36) questionnaires, which were performed before surgery, at 5 days after surgery and at the last follow-up, respectively. Relief of patients' symptoms was considered as the primary outcome. Secondary outcomes included lower esophageal sphincter pressure, esophageal emptying, quality of life of the patient, and procedure-related complications.

RESULTS

The two groups were matched in terms of age, gender, body mass index, and results of preoperative examinations. For patients with failed PD, it was observed that Eckardt score, lower esophageal sphincter pressure, and height of the barium column were significantly decreased after POEM surgery. Besides, the mean physical component summary and mental component summary of patients at the final follow were significantly higher than those before surgery. Complications that occurred during the surgery included three cases of subcutaneous emphysema (14.3%) and one case of pneumothorax (4.8%). Patients with failed PD were found to have the significantly longer operation time than the control group. There was no significant difference between the two groups in terms of surgical outcome at the final follow-up.

CONCLUSIONS

POEM is a promising therapeutic modality for achalasia patients who have failed to respond to PD therapy. Previous dilation procedures might have no obvious influence on the efficacy of POEM surgery.

Impedance Analysis Using High-resolution Impedance Manometry Facilitates Assessment of Pharyngeal Residue in Patients With Oropharyngeal Dysphagia

Background/Aims

Impedance analysis using high-resolution impedance manometry (HRIM) enables the recognition of pharyngeal residue in patients with oropharyngeal dysphagia. The aims of this study were to evaluate appropriate criteria for impedance analysis in a large patient cohort, as well as the diagnostic accuracy and agreement of analysis performed by HRIM trainees.

Methods

We reviewed 33 controls (13 males; median age, 61.2 years) and 104 oropharyngeal dysphagia patients (61 males; median age, 70.4 years) who underwent a flexible endoscopic evaluation of swallowing study (FEES) and HRIM. Two experts compared the pharyngeal residue on FEES and impedance color pattern at 1,000, 1,500 and 2,000 Ω of the impedance bar. Three trainees were given a 60 minutes tutorial to determine the diagnostic accuracy and agreement of this analysis.

Results

The diagnostic sensitivity of experts for predicting liquid residue was 73.1% for 1,000 Ω, 96.2% for 1,500 Ω and 100% for 2,000 Ω. Significantly higher sensitivity was observed at 1,500 Ω compared to 1,000 Ω (P < 0.001). The diagnostic specificity of experts for liquid residue was 98.3% for 1,000 Ω, 96.6% for 1,500 Ω and 83.1% for 2,000 Ω. There was a higher specificity at 1,500 Ω compared to 2,000 Ω (P = 0.008). The κ value among the 3 trainees was 0.89 and the diagnostic accuracy of the trainees for liquid residue was comparable to that of the experts.

Conclusions

The impedance analysis at 1,500 Ω provides more accurate information for the detection of liquid residue, irrespective of the level of expertise.

Effectiveness of peroral endoscopic myotomy in the treatment of achalasia: a pilot trial in Chinese Han population with a minimum of one-year follow-up

OBJECTIVE

To investigate the outcomes of Chinese Han patients who underwent peroral endoscopic myotomy (POEM) for achalasia.

METHODS

Patients undergoing POEM for achalasia at the Affiliated Drum Tower Hospital of Nanjing University Medical School were prospectively enrolled in this study, with a follow-up duration of at least one year. Their outcomes were evaluated by analyzing esophageal manometry, timed barium esophagogram and 36-Item Short Form Health Survey (SF-36), which were performed before surgery, 5 days after surgery and at the last follow-up. Patients' symptom relief was considered the primary outcome. Secondary outcomes included lower esophageal sphincter (LES) pressure, esophageal emptying, patients' quality of life (QoL) and procedure-related complications.

RESULTS

Eighty-seven patients were included in the study. Eckardt score after POEM was remarkably lower than the preoperative score (0.4 ± 0.7 vs 7.1 ± 2.1, P = 0.001). The preoperative LES pressure was 32.4 ± 15.3 mmHg, which was decreased to 3.8 ± 3.9 mmHg immediately after surgery. The height of the barium column at 1 min after barium swallow was significantly reduced after treatment (11.7 ± 1.2 cm vs 3.2 ± 1.6 cm, P < 0.001). The patients' QoL was also improved, as indicated by obviously increased physical and mental component summary (PCS and MCS) scores of the SF-36. Complications occurred during POEM included cutaneous emphysema, mucosal injury and pneumothorax.

CONCLUSION

POEM is an effective approach for treating achalasia, which can relieve the symptoms of achalasia by improving esophageal emptying and lowering LES pressure.

EndoFLIP system for the intraoperative evaluation of peroral endoscopic myotomy

BACKGROUND

Peroral endoscopic myotomy (POEM) has been recently introduced in clinical practice for the treatment of achalasia. The endoluminal functional lumen imaging probe (EndoFLIP) system) uses impedance planimetry for the real-time measurement of the diameter of the oesophago-gastric junction.

OBJECTIVE

The aim of this study is to prospectively evaluate the effect of POEM on the oesophago-gastric junction using EndoFLIP.

METHODS

All the patients who underwent POEM in a single centre between April and July 2013 were enrolled in the study. EndoFLIP was used intraoperatively, immediately before and after POEM. During follow-up patients underwent oesophagogastroduodenoscopy, oesophageal pH monitoring and manometry. Clinical outcomes were compared with the diameter of the oesophago-gastric junction after POEM.

RESULTS

In total, 23 patients (12 males, mean age 51.7 years) were enrolled, and 21 underwent POEM successfully. Preoperative mean basal lower oesophageal sphincter pressure was 42.1 mmHg (±17.6). Before POEM, the mean oesophago-gastric junction diameter and cross-sectional area were 6.3 mm (±1.8) and 32.9 mm(2) (±23.1), respectively. After treatment, the mean diameter and cross-sectional area of the oesophago-gastric junction were 11.3 mm (±1.7 SD) and 102.38 mm(2) (±28.2 SD), respectively. No complications occurred during a mean follow-up of 5 months. Median post-operative Eckardt score was 1. Three patients (14.3%) referred heartburn. Follow-up studies revealed gastro-oesophageal reflux disease (GORD) in 57.1% of patients and oesophagitis in 33.3%. No correlations were observed between the diameter of oesophago-gastric junction after POEM and symptoms relief, GORD incidence and lower oesophageal sphincter pressure.

CONCLUSIONS

The diameter of oesophago-gastric junction substantially increases after POEM. EndoFLIP is a reliable method for the intraoperative evaluation of oesophago-gastric junction diameter. However, the real usefulness of this technology after POEM remains controversial.

Endoscopic therapy for early gastric cancer: Standard techniques and recent advances in ESD

The technique of endoscopic submucosal dissection (ESD) is now a well-known endoscopic therapy for early gastric cancer. ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precision of histologic diagnosis and can also reduce the recurrence rate. However, the drawback of ESD is its technical difficulty, and, consequently, it is associated with a high rate of complications, the need for advanced endoscopic techniques, and a lengthy procedure time. Various advances in the devices and techniques used for ESD have contributed to overcoming these drawbacks.

Association between gastroesophageal reflux disease after pneumatic balloon dilatation and clinical course in patients with achalasia

Background/Aims

The occurrence of gastroesophageal reflux disease (GERD) is known to be associated with lower post-treatment lower esophageal sphincter pressure in patients with achalasia. This study aimed to elucidate whether GERD after pneumatic balloon dilatation (PD) has a prognostic role and to investigate how the clinical course of GERD is.

Methods

A total of 79 consecutive patients who were first diagnosed with primary achalasia and underwent PD as an initial treatment were included in this retrospective study. Single PD was performed using a 3.0 cm balloon. The patients were divided into two groups: 1) who developed GERD after PD (GERD group) and 2) who did not develop GERD after PD (non-GERD group). GERD was defined as pathological acid exposure, reflux esophagitis or typical reflux symptoms.

Results

Twenty one patients (26.6%) developed GERD after PD during follow-up. There were no significant differences between the two groups in demographic or clinical factors including pre- and post-treatment manometric results. All patients in GERD group were well responsive to maintenance proton pump inhibitor therapy including on demand therapy or did not require maintenance. During a median follow-up of 17.8 months (interquartile range, 7.1–42.7 months), achalasia recurred in 15 patients (19.0%). However, the incidence of recurrence did not differ according to the occurrence of GERD after PD.

Conclusions

GERD often occurs after even a single PD for achalasia. However, GERD after PD is well responsive to PPI therapy. Our data suggest that GERD after PD during follow-up does not appear to have a prognostic role.

Submucosal tunneling techniques: current perspectives

Advances in endoscopic submucosal dissection include a submucosal tunneling technique, involving the introduction of tunnels into the submucosa. These tunnels permit safer offset entry into the peritoneal cavity for natural orifice transluminal endoscopic surgery. Technical advantages include the visual identification of the layers of the gut, blood vessels, and subepithelial tumors. The creation of a mucosal flap that minimizes air and fluid leakage into the extraluminal cavity can enhance the safety and efficacy of surgery. This submucosal tunneling technique was adapted for esophageal myotomy, culminating in its application to patients with achalasia. This method, known as per oral endoscopic myotomy, has opened up the new discipline of submucosal endoscopic surgery. Other clinical applications of the submucosal tunneling technique include its use in the removal of gastrointestinal subepithelial tumors and endomicroscopy for the diagnosis of functional and motility disorders. This review suggests that the submucosal tunneling technique, involving a mucosal safety flap, can have potential values for future endoscopic developments.

MG132 reverse the malignant characteristics of hypopharyngeal cancer

In order to reverse the malignant characteristics of hypopharyngeal cancer, the proteasome inhibitor MG132 was introduced into FaDu/T cells and the mechanisms underlying its effects were investigated. The multi-drug resistance (MDR) sensitivities of FaDu/T and FaDu/T-MG132 cancer cells to several chemotherapeutics were investigated by a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) assay. Apoptosis was measured by staining cells with Annexin V and propidium iodide (PI) double staining. Reverse transcription-polymerase chain reaction and western blot analysis were conducted to detect mRNA and corresponding protein levels of the MDR- and apoptosis-related genes P-glycoprotein (P-gp), caspase-3, Bcl-2 and Bax. The nuclear protein of nuclear factor κ-light-chain-enhancer of activated B cells. (NF-κB) and p53 were also investigated via western blot analysis. Compared with FaDu/T cells, the drug resistance of FaDu/T + MG132 cells to cisplatin (DDP), 5-fluorouracil (5-FU), doxorubicin (Dox) and vincristine (VCR) decreased. With increased expression of caspase-3 and Bax and decreased expression of Bcl-2, the anti-apoptotic ability markedly decreased in FaDu/T + MG132 cells. P-gp and NF-κB significantly decreased; however, p53 increased in FaDu/T + MG132 cells. These results suggested that the proteasome inhibitor MG132 reversed the malignant characteristics of FaDu/T by enhancing apoptosis and inhibiting P-gp. MG132 was also able to inhibit the nuclear translocation of NF-κB and increase the expression of p53.

Early detection of colorectal cancer recurrence in patients undergoing surgery with curative intent: current status and challenges

Despite advances in neoadjuvant and adjuvant therapy, attention to proper surgical technique, and improved pathological staging for both the primary and metastatic lesions, almost half of all colorectal cancer patients will develop recurrent disease. More concerning, this includes ~25% of patients with theoretically curable node-negative, non-metastatic Stage I and II disease. Given the annual incidence of colorectal cancer, approximately 150,000 new patients are candidates each year for follow-up surveillance. When combined with the greater population already enrolled in a surveillance protocol, this translates to a tremendous number of patients at risk for recurrence. It is therefore imperative that strategies aim for detection of recurrence as early as possible to allow initiation of treatment that may still result in cure. Yet, controversy exists regarding the optimal surveillance strategy (high-intensity vs. traditional), ideal testing regimen, and overall effectiveness. While benefits may involve earlier detection of recurrence, psychological welfare improvement, and greater overall survival, this must be weighed against the potential disadvantages including more invasive tests, higher rates of reoperation, and increased costs. In this review, we will examine the current options available and challenges surrounding colorectal cancer surveillance and early detection of recurrence.

Peroral endoscopic myotomy for achalasia

BACKGROUND

Treatment of achalasia is complicated by symptom recurrence and a significant risk for severe complications. Endoscopic myotomy was developed in the search for a highly efficacious treatment with lower risks. Since its introduction in 2010, several centers have adopted the technique and published excellent short-term results of open label series. Randomized trials with long-term endpoint comparing per-oral endoscopic myotomy (POEM) with the established treatments such as balloon dilation and surgical myotomy are now warranted, before POEM can be regarded as the routine clinical care for achalasia patients.

PURPOSE

This review describes the development, technical aspects, efficacy, and complications of POEM.

Gastroduodenal outlet obstruction and palliative self-expandable metal stenting: a dual-centre experience

Background. Self-expandable metal stents (SEMs) are increasingly being utilised instead of invasive surgery for the palliation of patients with malignant gastroduodenal outlet obstruction. Aim. To review two tertiary centres' experience with placement of SEMs and clinical outcomes. Methods. Retrospective analysis of prospectively collected data over 12 years. Results. Ninety-four patients (mean age, 68; range 28–93 years) underwent enteral stenting during this period. The primary tumour was gastric adenocarcinoma in 27 (29%) patients, pancreatic adenocarcinoma in 45 (48%), primary duodenal adenocarcinoma in 8 (9%), and cholangiocarcinoma and other metastatic cancers in 14 (16%). A stent was successfully deployed in 95% of cases. There was an improvement in gastric outlet obstruction score (GOOS) in 84 (90%) of patients with the ability to tolerate an enteral diet. Median survival was 4.25 months (range 0–49) without any significant differences between types of primary malignancy. Mean hospital stay was 3 days (range 1–20). Reintervention rate for stent related complications was 5%. Conclusion. The successful deployment of enteral stents achieves excellent palliation often resulting in the prompt reintroduction of enteral diet and early hospital discharge with minimal complications and reintervention.

Peroral endoscopic myotomy for the treatment of achalasia: an analysis

Achalasia is a motility disorder of the esophagus, characterized by aperistalsis of the esophageal body and incomplete relaxation of the lower esophageal sphincter (LES). Treatment of achalasia is currently aimed at decreasing the resting pressure in the LES. Peroral endoscopic myotomy (POEM) is an emerging novel endoscopic procedure for the treatment of achalasia with initial data suggesting an acceptable safety profile, excellent short-term symptom resolution, low incidence of postprocedural gastroesophageal reflux (GER), and improvement in manometric outcomes. Further prospective randomized trials are required to evaluate the long-term effectiveness of this promising technique compared to other treatment modalities for achalasia. In this review we outline the technical aspects of POEM, summarize the available data on safety and outcomes, and suggest future directions for further advancement of this minimally invasive approach for the treatment of achalasia.

Research advances in esophageal diseases: bench to bedside

Over the last year, significant steps have been made toward understanding the pathogenesis of esophageal diseases and translating this knowledge to clinical practice. Gastroesophageal reflux disease (GERD) is the most common outpatient diagnosis in gastroenterology and has a high prevalence in the general population. As many as 40% of patients with GERD have incomplete response to medical therapy, and the pathophysiological mechanisms underlying lack of response are now better understood. Novel medical and minimally invasive interventions are available to optimize management of GERD. Esophageal cancer, regardless of the histological subtype, has among the worst survival statistics among all malignancies. Taking advantage of technological advances in genome sequencing, the mutational spectra in esophageal cancer are now emerging, offering novel avenues for targeted therapies. Early diagnosis is another strand for improving survival. While genome-wide association studies are providing insights into genetic susceptibility, novel approaches to early detection of cancer are being devised through the use of biomarkers applied to esophageal samples and as part of imaging technologies. Dysmotility and eosinophilic esophagitis are the differential diagnoses in patients with dysphagia. New pathophysiological classifications have improved the management of motility disorders. Meanwhile, exciting progress has been made in the endoscopic management of these conditions. Eosinophilic esophagitis is still a relatively new entity, and the pathogenesis remains poorly understood. However, it is now clear that an allergic reaction to food plays an important role, and dietary interventions as well as biologic agents to block the inflammatory cascade are novel, promising fields of clinical research.

Highlights of international digestive endoscopy network 2013

Rapid advances in the technology of gastrointestinal endoscopy as well as the evolution of science have made it necessary for us to continue update in either various endoscopic techniques or state of art lectures relevant to endoscopy. International Digestive Endoscopy Network (IDEN) 2013 was held in conjunction with Korea-Japan Joint Symposium on Gastrointestinal Endoscopy (KJSGE) during June 8 to 9, 2013 at Seoul, Korea. Two days of impressive scientific program dealt with a wide variety of basic concerns from upper gastrointestine (GI), lower GI, pancreaticobiliary endoscopy to advanced knowledge including endoscopic submucosal dissection forum. IDEN seems to be an excellent opportunity to exchange advanced information of the latest issues on endoscopy with experts from around the world. In this special issue of Clinical Endoscopy, we prepared state of art review articles from contributing authors and the current highlights will skillfully deal with very hot spots of each KJSGE, upper GI, lower GI, and pancreaticobiliary sessions by associated editors of Clinical Endoscopy.

Current status in the treatment options for esophageal achalasia

Recent advances in the treatment of achalasia include the use of high-resolution manometry to predict the outcome of patients and the introduction of peroral endoscopic myotomy (POEM). The first multicenter randomized, controlled, 2-year follow-up study conducted by the European Achalasia Trial group indicated that laparoscopic Heller myotomy (LHM) was not superior to pneumatic dilations (PD). Publications on the long-term success of laparoscopic surgery continue to emerge. In addition, laparoscopic single-site surgery is applicable to advanced laparoscopic operations such as LHM and anterior fundoplication. The optimal treatment option is an ongoing matter of debate. In this review, we provide an update of the current progress in the treatment of esophageal achalasia. Unless new conclusive data prove otherwise, LHM is considered the most durable treatment for achalasia at the expense of increased reflux-associated complications. However, PD is the first choice for non-surgical treatment and is more cost-effective. Repeated PD according to an “on-demand” strategy based on symptom recurrence can achieve long-term remission. Decision making should be based on clinical evidence that identifies a subcategory of patients who would benefit from specific treatment options. POEM has shown promise but its long-term efficacy and safety need to be assessed further.