Mixed reflux of gastric and duodenal juices is more harmful to the esophagus than gastric juice alone. The need for surgical therapy re-emphasized

Can Incidental Gastric GISTs During Bariatric Surgeries Change the Primary Plan of Surgery? A Single Team Experience and a Systematic Review of Literature

As bariatric surgeries (BS) increase, more incidental findings are liable to be discovered. Incidental gastric gastrointestinal stromal tumors (GISTs) during BS can be found in around 0.7% of the cases. In this article, we have performed a systematic review of the literature and added our data to those of the review to review a conceptual treatment strategy to both improve patient outcomes and decrease the risk of overall cancer. With the rise of new bariatric techniques, we have proposed a new classification to BS to enhance our description of the treatment strategy.

Chemoprevention of esophageal adenocarcinoma in a rat surgical model by a cysteinyl leukotriene receptor‑1 antagonist

Reflux of gastroduodenal contents into the esophagus leads to the development of esophagitis and inflammation-associated pathologies, such as Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). The role of the lipoxygenase (LOX) pathway in carcinogenesis has been recently reported; however, its involvement in esophageal carcinogenesis remains unclear. To address this, the present study investigated the potential of pranlukast, a cysteinyl leukotriene receptor-1 antagonist, to suppress the progression of BE and EAC in a rat duodenogastroesophageal reflux (DGER) model. Male Wistar rats that underwent DGER were divided into two groups. One group was fed commercial chow (control group), and the other was fed experimental chow containing pranlukast (pranlukast group). The rats were sacrificed at 10, 20, 30 and 40 weeks after surgery, and their esophagi were examined. Expression levels of 5-LOX, CD68, IL-8, VEGF and Ki-67 were investigated using immunohistochemistry, and apoptosis was analyzed using the TUNEL method. In the pranlukast group, esophagitis was milder, and the incidence of BE and EAC was significantly lower (P<0.05) compared with that in the control group at 40 weeks after surgery. The number of cells positive for IL-8 and VEGF were significantly lower in the pranlukast group compared with the control group. Proliferative activity was also lower in the pranlukast group compared with the control group (P<0.05). Pranlukast treatment increased apoptosis (P<0.05). Overall, Pranlukast suppressed esophageal carcinogenesis in a rat DGER model, decreasing inflammatory cytokines such as IL-8 and VEGF.

Long-term (18 Years) Results of Patients With Long-segment Barrett Esophagus Submitted to Acid Suppression-duodenal Diversion Operation: Better Than Nissen Fundoplication?

OBJECTIVE

To determine late results of AS-DD procedure in long-segment (LSBE) and extralong-segment BE (ELSBE) using subjective and objective measurements to ascertain the histological impact over intestinal metaplasia (IM) and progression to EAC.

SUMMARY OF BACKGROUND DATA

Barrett esophagus (BE) is a known precursor of esophageal adenocarcinoma (EAC), and Nissen fundoplication has proven to be unable to stop mixed reflux among them. Our group proposed a surgical procedure that handles pathophysiological changes responsible for BE.

METHODS

This prospective study included 127 LSBE and ELSBE subjects submitted to clinical and functional analyses. They were presented to selective vagotomy, fundoplication, partial gastrectomy with Roux-en-Y reconstruction. The changes in IM were determined in both groups.

RESULTS

Follow-up was completed at a mean of 18 years in 81% of the cases. Visick I-II scores were seen in 88% of LSBE and 65% in ELSBE ( P < 0.01). There was significant healing of erosive esophagitis and esophageal peptic ulcers, and strictures were resolved in 71%. There was 38% of IM regression in LSBE. Two cases in each group progressed to EAC at a mean of 15 years. Pathologic acid reflux was abolished in 91% and duodenal in 100%. There was a regression of low-grade dysplasia to IM in 80%.

CONCLUSIONS

AS-DD permanently eliminates pathologic refluxate to the esophagus. The progression to HGD/EAC is lower compared to medical treatment, with an 8-fold reduction in LSBE and 2.2-fold in ELSBE. AS-DD seems to influence IM behaviors, and it is a tool that could reduce and delay progression to EAC.

Increased PXR and Suppressed T-Cell Signaling Are Associated With Malignant Degeneration of Barrett's Esophagus

Background and Aims

Barrett's esophagus (BE) is the precursor lesion for esophageal adenocarcinoma (EAC). To detect EAC in early stage, patients with BE undergo endoscopic surveillance. Surveillance cohorts largely consist of nondysplastic BE (NDBE) patients with a low annual progression risk (<0.5%). Predictive biomarkers for malignant progression of NDBE could improve efficacy of surveillance. Biomarker research has mostly focused on aberrant protein expression on BE epithelial cells. Moreover, insight in cell signaling driving malignant transformation is unknown. This study uses a data-driven approach to analyze tumor-stroma interaction in NDBE which progressed to high-grade dysplasia or EAC.

Methods

In this case-control study, we performed RNA sequencing analysis on index NDBE biopsies from 6 patients who, during long-term follow-up, progressed and 7 who did not progress to high-grade dysplasia/EAC. For control samples, squamous and duodenum tissues from BE patients were analyzed. For validation, we used quantitative PCR.

Results

Significant differences in BE transcriptomic profiles between progressors and nonprogressors were found by principal component and differential expression analyses. Ingenuity pathway analysis indicated that 8 cell signaling pathways were significantly upregulated in the progressors, and 14 pathways were significantly downregulated. The most interesting finding was the upregulation of the xenobiotic metabolism pregnane X receptor signaling pathway in the progressor cohort, while of the downregulated pathways in progressors, several were related to the immune system.

Conclusion

These novel transcriptomic insights are fundamental for developing (chemo-)preventive therapies. These could be therapies, which protect against toxins, including biles, responsible for pregnane X receptor activation or which enhance protective immune mechanisms. The identified RNA markers are promising biomarkers for improving risk stratification in surveillance programs.

Kyoto international consensus report on anatomy, pathophysiology and clinical significance of the gastro-oesophageal junction

OBJECTIVE

An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

DESIGN

Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement. Two rounds of voting and amendments were completed before the meeting at which clinical questions and consensus were finalised.

RESULTS

Twenty eight clinical questions and statements were finalised after extensive amendments. Critical consensus was achieved: (1) definition for the GOJ, (2) definition of the GOJZ spanning 1 cm proximal and distal to the GOJ as defined by the end of palisade vessels was accepted based on the anatomical distribution of cardiac type gland, (3) chemical and bacterial (Helicobacter pylori) factors as the primary causes of inflammation, metaplasia and neoplasia occurring in the GOJZ, (4) a new definition of Barrett's oesophagus (BO).

CONCLUSIONS

This international consensus on the new definitions of BO, GOJ and the GOJZ will be instrumental in future studies aiming to resolve many issues on this important anatomic area and hopefully will lead to better classification and management of the diseases surrounding the GOJ.

Cross-talk between the microbiome and chronic inflammation in esophageal cancer: potential driver of oncogenesis

Esophageal cancer (EC) is frequently considered a lethal malignancy and is often identified at a later stage. It is one of the major causes of cancer-related deaths globally. The conventional treatment methods like chemotherapy, radiotherapy, and surgery offer limited efficacy and poor clinical outcome with a less than 25% 5-year survival rate. The poor prognosis of EC persists despite the growth in the development of diagnostic and therapeutic modalities to treat EC. This underlines the need to elucidate the complex molecular mechanisms that drive esophageal oncogenesis. Apart from the role of the tumor microenvironment and its structural and cellular components in tumorigenesis, mounting evidence points towards the involvement of the esophageal microbiome, inflammation, and their cross-talk in promoting esophageal cancer. The current review summarizes recent research that delineates the underlying molecular mechanisms by which the microbiota and inflammation promote the pathophysiology of esophageal cancer, thus unraveling targets for potential therapeutic intervention.

GORD and Barrett's oesophagus after bariatric procedures: multicentre prospective study

INTRODUCTION

Gastro-oesophageal reflux disease (GORD) after bariatric surgery is a debated topic. This study investigated the prevalence of GORD and associated oesophageal complications following bariatric procedures-namely, adjustable gastric banding (AGB), sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one-anastomosis gastric bypass (OAGB).

METHODS

This was a prospective multicentre study designed to evaluate the long-term effects of bariatric surgery on GORD. Patients were studied at baseline, at >10 years following AGB, SG, and RYGB, and at >3 years following OAGB (due to the more recent recognition of OAGB as a standard bariatric procedure). Patients were assessed by endoscopy and GORD symptom evaluation.

RESULTS

A total of 241 patients were enrolled. A minimum follow-up of 10 years was completed by 193 patients following AGB (57 patients), SG (95 patients), and RYGB (41 patients), and of >3 years by 48 subjects following OAGB. GORD symptoms increased following AGB and SG (from 14 to 31.6 per cent and from 26.3 to 58.9 per cent, respectively; P < 0.0001), improved following RYGB (from 36.6 to 14.6 per cent; P < 0.0001), and were unchanged following OAGB. The overall prevalence of erosive oesophagitis was greater in the SG group (74.7 per cent) than in the AGB (42.1 per cent), RYGB (22 per cent), and OAGB (22.9 per cent) groups (P < 0.0001). Barrett's oesophagus was found only in patients who had SG (16.8 per cent). Biliary-like gastric stagnation was found in a greater proportion of SG and OAGB patients (79.7 and 69.4 per cent, respectively) than in other treatment groups (P < 0.0001). The prevalence of biliary-type reflux into the oesophagus was higher in patients who underwent SG (74.7 per cent), compared with other treatment groups.

CONCLUSION

Bariatric surgery leads to gastro-oesophageal complications of variable severity, particularly SG, which can result in a large proportion of patients developing Barrett's oesophagus.

Machine Learning for Future Subtyping of the Tumor Microenvironment of Gastro-Esophageal Adenocarcinomas

Tumor progression involves an intricate interplay between malignant cells and their surrounding tumor microenvironment (TME) at specific sites. The TME is dynamic and is composed of stromal, parenchymal, and immune cells, which mediate cancer progression and therapy resistance. Evidence from preclinical and clinical studies revealed that TME targeting and reprogramming can be a promising approach to achieve anti-tumor effects in several cancers, including in GEA. Thus, it is of great interest to use modern technology to understand the relevant components of programming the TME. Here, we discuss the approach of machine learning, which recently gained increasing interest recently because of its ability to measure tumor parameters at the cellular level, reveal global features of relevance, and generate prognostic models. In this review, we discuss the relevant stromal composition of the TME in GEAs and discuss how they could be integrated. We also review the current progress in the application of machine learning in different medical disciplines that are relevant for the management and study of GEA.

Bile reflux and hypopharyngeal cancer (Review)

Laryngopharyngeal reflux, a variant of gastroesophageal reflux disease, has been considered a risk factor in the development of hypopharyngeal cancer. Bile acids are frequently present in the gastroesophageal refluxate and their effect has been associated with inflammatory and neoplastic changes in the upper aerodigestive tract. Recent in vitro and in vivo studies have provided direct evidence of the role of acidic bile refluxate in hypopharyngeal carcinogenesis and documented the crucial role of NF-κB as a key mediator of early oncogenic molecular events in this process and also suggested a contribution of STAT3. Acidic bile can cause premalignant changes and invasive squamous cell cancer in the affected hypopharynx accompanied by DNA damage, elevated p53 expression and oncogenic mRNA and microRNA alterations, previously linked to head and neck cancer. Weakly acidic bile can also increase the risk for hypopharyngeal carcinogenesis by inducing DNA damage, exerting anti-apoptotic effects and causing precancerous lesions. The most important findings that strongly support bile reflux as an independent risk factor for hypopharyngeal cancer are presented in the current review and the underlying mechanisms are provided.

Toll-like Receptor 4 Mediates Reflux-Induced Inflammation in a Murine Reflux Model

Dysregulation of toll-like receptor (TLR) signaling within the gastrointestinal epithelium has been associated with uncontrolled inflammation and tumorigenesis. We sought to evaluate the role of TLR4 in the development of gastroesophageal reflux-mediated inflammation and mucosal changes of the distal esophagus. Verified human esophageal Barrett's cells with high grade dysplasia (CPB) and esophageal adenocarcinoma cells (OE33) were treated with deoxycholic acid for 24 hours. Cells were pretreated with a TLR4-specific inhibitor peptide 2 hours prior to deoxycholic acid treatment. Inflammatory markers were evaluated using immunoblotting and enzyme-linked immunosorbent assay. A surgical reflux mouse model was generated by performing a side-to-side anastomosis between the second portion of the duodenum and the gastroesophageal junction. Control animals underwent laparotomy with incision and closure of the esophagus superior to the gastroesophageal junction (sham procedure). Esophageal sections were evaluated using hematoxylin and eosin staining and immunohistochemistry. Deoxycholic acid increased expression of inflammatory markers including intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and interleukin 8. Pretreatment with a TLR4 inhibitor significantly decreased deoxycholic acid-induced inflammatory marker expression. C3H/HeNCrl mice demonstrated a significant increase in mucosal hyperplasia and proliferation following DGEA compared to sham procedure. TLR4 mutant mice (C3H/HeJ) undergoing DGEA demonstrated an attenuated hyperplastic and proliferative response compared to C3H/HeNCrl mice. Inhibition of TLR4 signaling attenuates reflux-induced inflammation in vivo. These findings identify TLR4 inhibition as a potential therapeutic target to halt the progression of pathologic esophageal changes developing in the setting of chronic gastroesophageal reflux disease.

Fundoplication is superior to medical therapy for Barrett's esophagus disease regression and progression: a systematic review and meta-analysis

BACKGROUND

Fundoplication and medical management are current mainstays for management of Barrett's esophagus (BE), however our understanding of differences in outcomes between these two treatments is limited. The aim of this study was to perform a systematic review and meta-analysis to evaluate the efficacy of these interventions on BE disease regression and progression.

METHODS AND PROCEDURES

A comprehensive search in MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Library databases was performed on February 22, 2021. Inclusion criteria were studies with both medical and surgical management comparators, BE diagnosis prior to treatment, patients aged ≥ 18 years, and studies with greater than five patients. Primary outcomes of interest included evaluating changes in histopathologic BE regression and disease progression between interventions. Meta-analysis was performed using a Mantel-Haenszel random-effects model (RevMan 5.4.1).

RESULTS

A total of 7231 studies were retrieved after initial search with nine studies (1 randomized trial, 7 prospective cohorts, 1 retrospective cohort) meeting final inclusion criteria. Of included studies, 890 (65%) patients received medical management while 470 (35%) received surgical management. Medical management included proton pump inhibitors (n = 807, 91%; 6 studies), H2-receptor blockers (n = 40, 4% patients; 3 studies), and combination therapy (n = 43, 5%; 1 study). Nissen fundoplication was the most commonly performed type of fundoplication (n = 265, 93%). Median length of follow-up ranged from 1.5-7 years. Meta-analysis revealed that fundoplication was associated with improved histopathologic regression of metaplasia/low-grade dysplasia (OR 4.38; 95% CI 2.28-8.42; p < 0.00001) and disease progression to dysplasia/adenocarcinoma (OR 0.34; 95% CI 0.12-0.96; p = 0.04) compared to medical therapy.

CONCLUSION

Fundoplication is superior to medical therapy with regards to improved odds of histopathologic BE disease regression and disease progression. Additional randomized trials which directly compare medical management and surgical intervention are required to delineate the optimal delivery and timing of these interventions.

Drug-Loaded, Polyurethane Coated Nitinol Stents for the Controlled Release of Docetaxel for the Treatment of Oesophageal Cancer

For several decades, self-expanding metal stents (SEMSs) have shown significant clinical success in the palliation of obstructive metastatic oesophageal cancer. However, these conventional oesophageal stents can suffer from stent blockage caused by malignant tumour cell growth. To overcome this challenge, there is growing interest in drug-releasing stents that, in addition to palliation, provide a sustained and localized release of anticancer drugs to minimise tumour growth. Therefore, in this study we prepared and evaluated an oesophageal stent-based drug delivery platform to provide the sustained release of docetaxel (DTX) for the treatment of oesophageal cancer-related obstructions. The DTX-loaded oesophageal stents were fabricated via dip-coating of bare nitinol stents with DTX-polyurethane (PU) solutions to provide PU coated stents with DTX loadings of 1.92 and 2.79% w/w. Mechanical testing of the DTX-PU coated stents revealed that an increase in the drug loading resulted in a reduction in the ultimate tensile strength, toughness and Young’s modulus. In vitro release studies showed a sustained release of DTX, with ~80–90% released over a period of 33 days. While the DTX-loaded stents exhibited good stability to gamma radiation sterilisation, UV sterilisation or accelerated storage at elevated temperatures (40 °C) resulted in significant DTX degradation. Cell proliferation, apoptosis and Western blotting assays revealed that the DTX released from the stents had comparable anticancer activity to pure DTX against oesophageal cancer cells (KYSE-30). This research demonstrates that the dip-coating technique can be considered as a promising approach for the fabrication of drug-eluting stents (DESs) for oesophageal cancer treatment.

Evaluation of reflux following sleeve gastrectomy and one anastomosis gastric bypass: 1-year results from a randomized open-label controlled trial

Background

Recent reports have demonstrated that de novo reflux and worsening of pre-existing symptoms occur after SG; concerns are still expressed about the risk of symptomatic biliary reflux gastritis and oesophagitis. The aim of our study was to investigate and compare the rate of postoperative acid and non-acid reflux following Mini-/One anastomosis gastric bypass (MGB/OAGB) and laparoscopic sleeve gastrectomy (LSG).

Study design

A prospective randomized open-label, controlled trial registered on clinicaltrial.gov (NCT number: NCT02987673) has been carried out to evaluate esophagogastric junction exposure to reflux in the first year after MGB/OAGB and LSG using high impedance manometry, endoscopy, and a validated questionnaire.

Results

A total of 58 individuals were eventually enrolled in this trial and represented the per-protocol population (n = 28 MGB/OAGB, n = 30 LSG). No difference was found between the two groups in terms of demographic characteristics, PAGI-SYM score, acid exposure time percent of the esophagus (AET%), esophagitis, and other HRiM and MII-pH data at baseline. Comparing MII-pH outcomes of the two groups, AET% resulted significantly higher after LSG at 12 months. Endoscopic findings showed a significant increase of esophagitis ≥ B in the LSG group after 1 year; postoperative esophagitis ≥ B resulted also significantly worsened after LSG when compared to MGB/OAGB.

Conclusion

Since AET% and rate of esophagitis are significantly higher after LSG when compared to MGB/OAGB, this procedure should be preferred in case of preoperative subclinical reflux or low grade (A) esophagitis.

Esophageal adenocarcinoma after sleeve gastrectomy: actual or potential threat? Italian series and literature review

BACKGROUND

Sleeve gastrectomy (SG) leads to esophageal mucosal damage in an elevated percentage of cases, configuring a clinical condition of Barrett's esophagus (BE) in a proportion as high as 15-18.8%. BE may rarely evolve into esophageal adenocarcinoma (EAC).

OBJECTIVES

To raise awareness of BE as a precancerous lesion which may progress toward malignancy after this popular bariatric procedure.

SETTING

Bariatric referral centers, Italy.

METHODS

All patients referred to our bariatric center who developed an EAC after SG between 2012 and 2019 were reviewed and consecutively included in this study. The available scientific literature regarding this complication is additionally reviewed.

RESULTS

The 3 male patients comprised in this case series underwent laparoscopic SG between 2012 and 2015 in different bariatric referral centers. Age and body mass index at baseline ranged from 21-54 years and 43.1-75.6 kg/m², respectively. All patients were lost to follow-up early after surgery (3.7 ± 1.4 months), and were diagnosed with EAC at a mean of 27.3 ± 7.6 months after SG. The 4 reported cases in the scientific literature developed an EAC at a mean of 32.5 ± 23 months from SG. Overall, a diagnosis of EAC was made approximately 30.3 ± 17.1 months postoperatively, which seems relatively and worryingly early after surgery.

CONCLUSION

Although the rate and probability of progression from BE to EAC is still not well defined, assuming that the rising popularity and execution of SG leads to a growth in the BE incidence, then the preoperative identification and stratification of cancer risk factors in this subset of patients is strongly encouraged. Clinical and endoscopic follow-ups are essential to allow for prevention and early diagnosis and for epidemiologic data collection purposes.

Duration of adhesion of swallowed alginates to distal oesophageal mucosa: implications for topical therapy of oesophageal diseases

BACKGROUND

We have previously shown, ex vivo, that alginate solutions can have a topical protective effect on oesophageal mucosal biopsies exposed to simulated gastric juice. Oesophageal mucosal impedance can measure the duration of mucosal adherence of ionic solutions since the impedance drops when the solution is present, and rises to baseline as the solution clears.

AIM

To investigate the in vivo duration of adhesion of swallowed alginate solution to distal oesophageal mucosa.

METHODS

We studied 20 healthy volunteers and 10 patients with heartburn. A pH-impedance catheter was inserted, and baseline distal channel oesophageal impedance measured. Healthy volunteers received 10 mL of either sodium alginate (Gaviscon Advance), Gaviscon placebo (no alginate) or viscous slurry (saline mixed with sucralose), given in a randomised, single-blinded order over three visits. Patients received either sodium alginate or placebo on two visits. Initial impedance drop was measured, then 1-minute mean impedance was measured each minute until ≥75% recovery to baseline.

RESULTS

In healthy volunteers, sodium alginate adhered to the oesophageal mucosa for longer than placebo or viscous slurry (10.4 [8.7] minutes vs 1.1 [1.6] vs 3.6 [4.0], P < 0.01). In patients, sodium alginate adhered to the oesophageal mucosa for longer than placebo (9.0 (5.4) vs 3.7 (4.1), P < 0.01).

CONCLUSIONS

Sodium alginate solution adhered to the oesophageal mucosa for significantly longer than placebo or viscous slurry. This demonstrates that alginates could confer a protective benefit due to mucoadhesion and can be a basis for further development of topical protectants and for topical drug delivery in oesophageal disease.

Bariatric Surgery and Its Complications in Inflammatory Bowel Disease Patients

Recent data have suggested that bariatric procedures, especially laparoscopic sleeve gastrectomy (SG), are safe and effective weight loss measures in patients with inflammatory bowel disease (IBD). But most of the studies have looked at short-term outcomes, and there is a general lack of awareness of underlying disease processes and baseline comorbidities in IBD patients undergoing bariatric procedures. Postbariatric issues in IBD patients including diarrhea from dumping syndrome, choleretic diarrhea, a high prevalence of small intestinal bacterial overgrowth, gastroesophageal reflux disease, Barrett's esophagus, stomal ulcerations, stenosis, and renal and gallstones can complicate the natural history of IBD. This could lead to unnecessary hospitalizations, change of medical therapy, and poor surgical and quality of life outcomes. In this review, we will discuss major complications after common bariatric procedures (SG, Roux-en-Y gastric bypass, and gastric banding) and suggest possible management strategies.

Gastroesophageal Reflux Poses a Potential Risk for Late Complications of Bronchopulmonary Dysplasia: A Prospective Cohort Study

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the most common respiratory disorder in extremely low birth weight infants. Although most symptoms of BPD improve, some late complications exist, even with regular treatment. Gastroesophageal reflux (GER), also common in extremely premature infants, may be related to many cardiorespiratory symptoms. However, the potential of GER as a risk factor for late complications associated with BPD is still unclear.

RESEARCH QUESTION

The goal of this study was to determine if GER increases the risk of late complications of BPD in infants.

STUDY DESIGN AND METHODS

A multicenter prospective cohort of 131 infants (79 male subjects, 52 female subjects) with BPD was enrolled. The development of late complications was assessed over an 18-month follow-up period. Twenty-four-hour pH-multichannel intraluminal impedance and gastric sodium concentrations were analyzed in all infants at 36 weeks' postmenstrual age and at the last interview. Prevalence and risk factors of late complications of BPD were analyzed by using forward logistic regression.

RESULTS

The prevalence of late complications in BPD infants was 63.79% and included respiratory symptoms (49.14%), vomiting (38.79%), retinopathy of prematurity (25.86%), hypoxic-ischemic injury (3.45%), rehospitalization (26.72%), and sudden death (0.86%). Respiratory diseases constituted the most frequent complication. The prevalence of GER in BPD was 42.24% and included acid GER (18.10%) and duodenogastroesophageal reflux (DGER; 24.14%). Risk factors for respiratory symptoms were gestational age ≤ 30 weeks (OR, 3.213; 95% CI, 1.221-8.460), birth weight < 1,500 g (OR, 2.803; 95% CI, 1.014-7.749), invasive ventilation > 7 days (OR, 4.952; 95% CI, 1.508-16.267), acid GER (OR, 4.630; 95% CI, 1.305-16.420), and DGER (OR, 5.588; 95% CI, 1.770-17.648). Infants with BPD and DGER were more prone to late complications than those with acid GER or no reflux.

INTERPRETATION

The prevalence of late complications is high in infants with BPD. GER (and in particular, DGER) poses a tentative risk for these late complications.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03014453; URL: www.clinicaltrials.gov.

The Progressive Mutagenic Effects of Acidic Bile Refluxate in Hypopharyngeal Squamous Cell Carcinogenesis: New Insights

Cancers of the laryngopharynx represent the most devastating of the head and neck malignancies and additional risk factors are now epidemiologically linked to this disease. Using an in vivo model (Mus musculus C57Bl/6J), we provide novel evidence that acidic bile (pH 3.0) progressively promotes invasive cancer in the hypopharynx. Malignant lesions are characterized by increasing: i) oxidative DNA-damage, ii) γH2AX expression, iii) NF-κB activation, and iv) p53 expression. Histopathological changes observed in murine hypopharyngeal mucosa exposed to acidic bile were preceded by the overexpression of Tnf, Il6, Bcl2, Egfr, Rela, Stat3, and the deregulation of miR-21, miR-155, miR-192, miR-34a, miR-375, and miR-451a. This is the first study to document that acidic bile is carcinogenic in the upper aerodigestive tract. We showed that oxidative DNA-damage produced by acidic bile in combination with NF-κB-related anti-apoptotic deregulation further supports the underlying two-hit hypothesized mechanism. Just as importantly, we reproduced the role of several biomarkers of progression that served as valuable indicators of early neoplasia in our experimental model. These findings provide a sound basis for proposing translational studies in humans by exposing new opportunities for early detection and prevention.

Obesity Surgery and Cancer: What Are the Unanswered Questions?

Obesity has become a global epidemic with a soaring economic encumbrance due to its related morbidity and mortality. Amongst obesity-related conditions, cancer is indeed the most redoubtable. Bariatric surgery has been proven to be the most effective treatment for obesity and its associated metabolic and cardiovascular disorders. However, the understanding of whether and how bariatric surgery determines a reduction in cancer risk is limited. Obesity-related malignancies primarily include colorectal and hormone-sensitive (endometrium, breast, prostate) cancers. Additionally, esophago-gastric tumors are growing to be recognized as a new category mainly associated with post-bariatric surgery outcomes. In fact, certain types of surgical procedures have been described to induce the development and subsequent progression of pre-cancerous esophageal and gastric lesions. This emerging category is of great concern and further research is required to possibly prevent such risks. Published data has generated conflicting results. In fact, while overall cancer risk reduction was reported particularly in women, some authors showed no improvement or even increased cancer incidence. Although various studies have reported beneficial effects of surgery on risk of specific cancer development, fundamental insights into the pathogenesis of obesity-related cancer are indispensable to fully elucidate its mechanisms.

How to select patients for antireflux surgery? The ICARUS guidelines (international consensus regarding preoperative examinations and clinical characteristics assessment to select adult patients for antireflux surgery)

OBJECTIVE

Antireflux surgery can be proposed in patients with GORD, especially when proton pump inhibitor (PPI) use leads to incomplete symptom improvement. However, to date, international consensus guidelines on the clinical criteria and additional technical examinations used in patient selection for antireflux surgery are lacking. We aimed at generating key recommendations in the selection of patients for antireflux surgery.

DESIGN

We included 35 international experts (gastroenterologists, surgeons and physiologists) in a Delphi process and developed 37 statements that were revised by the Consensus Group, to start the Delphi process. Three voting rounds followed where each statement was presented with the evidence summary. The panel indicated the degree of agreement for the statement. When 80% of the Consensus Group agreed (A+/A) with a statement, this was defined as consensus. All votes were mutually anonymous.

RESULTS

Patients with heartburn with a satisfactory response to PPIs, patients with a hiatal hernia (HH), patients with oesophagitis Los Angeles (LA) grade B or higher and patients with Barrett's oesophagus are good candidates for antireflux surgery. An endoscopy prior to antireflux surgery is mandatory and a barium swallow should be performed in patients with suspicion of a HH or short oesophagus. Oesophageal manometry is mandatory to rule out major motility disorders. Finally, oesophageal pH (±impedance) monitoring of PPI is mandatory to select patients for antireflux surgery, if endoscopy is negative for unequivocal reflux oesophagitis.

CONCLUSION

With the ICARUS guidelines, we generated key recommendations for selection of patients for antireflux surgery.

Role of Kruppel-Like Factor 5 in Deoxycholic Acid-Mediated Intestinal Transdifferentiation of Esophageal Squamous Epithelium

Barrett's esophagus (BE) is an acquired condition in which normal squamous epithelium is replaced with metaplastic columnar epithelium as a consequence of gastroesophageal reflux disease. BE is known as a precursor of esophageal adenocarcinoma. Currently, the molecular mechanism underlying epithelial metaplasia in BE patients remains unknown. Therefore, we investigated the role of Krüppel-like factor 5 (KLF5) signaling in the initiation of BE-associated metaplasia. Sprague-Dawley (SD) rats were used to create a surgical model of bile reflux injury. Immunohistochemistry was performed to analyze human and mouse esophageal specimens. Human esophageal squamous epithelial (HET-1A) cells were treated with bile acid and used in transfection experiments. Quantitative real-time PCR and western blot analysis were performed to detect the expression of KLF5, CDX2, MUC2 and villin. Epithelial tissue from both the rat BE model and human BE patients strongly expressed KLF5, CDX2, MUC2, and villin. Bile acid treatment also increased the expression of KLF5, CDX2, MUC2 and villin in esophageal epithelial cells in a time-dependent manner. Moreover, siRNA-mediated knockdown of KLF5 blocked the expression of CDX2, MUC2 and villin, but transfection of a KLF5 expression vector into esophageal epithelial cells promoted their transdifferentiation into columnar-like cells, as demonstrated by increased expression of the intestinal markers CDX2, MUC2 and villin. Thus, in addition to its function as a transcription factor, KLF5 may be linked to an increased risk of BE development.

Glyco-conjugated bile acids drive the initial metaplastic gland formation from multi-layered glands through crypt-fission in a murine model

Bile acid reflux is known to be associated with the development of Barrett’s esophagus and esophageal adenocarcinoma (EAC), yet the role of specific bile acids and the mechanism behind the metaplastic changes is unclear. Here, we demonstrate that multi-layered glandular structures at the squamo-columnar junction in mice contain multiple cell lineages, which resemble the human esophageal submucosal gland ducts. Exposing mice to patient’s refluxates induced expansion of multi-layered glandular structures and development of columnar metaplasia at the squamo-columnar junction. The glycine conjugated bile acids induced an intestinal type of metaplasia more typical for Barrett’s esophagus. Through lineage tracing, we excluded the involvement of K5⁺, DCLK1⁺, and LGR5⁺ progenitor cells as the primary source in the development of the glandular metaplastic epithelium. We show that the mechanism behind development of metaplasia involves crypt fission and may be independent of stem cell proliferation. Our findings support the hypothesis that in humans, BE arises from non-squamous cells residing in submucosal gland ducts and that induction of intestinal type of metaplasia is most effectively induced by glycine-conjugated bile acids. These novel insights may lead to more effective strategies to prevent development of Barrett’s esophagus and esophageal adenocarcinoma.

Gastroesophageal reflux-related physiologic changes after sleeve gastrectomy and Roux-en-Y gastric bypass: a prospective comparative study

BACKGROUND

The development of gastroesophageal reflux disease (GERD) after laparoscopic sleeve gastrectomy (LSG) is a major concern as it affects the quality of life of the patients and potentially exposes them to the complications of GERD. The reported incidence of GERD after LSG is up to 35%. Laparoscopic Roux-en-Y gastric bypass (LRYGB) is considered the procedure of choice for patients with morbid obesity with GERD but objective evidence based on physiologic studies for the same are limited.

OBJECTIVE

The objectives of the study were to determine the physiologic changes related to gastroesophageal reflux based on symptoms index, 24-hour pH study, impedance, and manometry after LSG and LRYGB.

SETTINGS

Tertiary care teaching hospital, India.

METHODS

This registered study (CTRI/2017/06/008834) is a prospective, nonrandomized, open-label clinical trial comparing the incidence of GERD after LSG and LRYGB. In this study, non-GERD patients were evaluated for GERD based on clinical questionnaires, 24-hour pH study, and impedance manometry preoperatively and 6 months postoperatively.

RESULTS

Thirty patients underwent LSG, and 16 patients underwent LRYGB. The mean DeMeester score increased from 10.9 ± 11.8 to 40.2 ± 38.6 (P = .006) after LSG. The incidence of GERD after LSG was 66.6%. The increase in DeMeester score from 9.5 ± 4.6 to 12.2 ± 17.2 after LRYGB was not significant (P = .7). There was a significant increase in the nonacid reflux both after LSG and LRYGB.

CONCLUSION

The incidence of GERD after LSG is high, making it a contraindication for LSG. LRYGB remains the preferred procedure for patients with GERD. However, more studies are needed to understand the physiologic changes in patients with preexisting GERD.

Bile acids at neutral and acidic pH induce apoptosis and gene cleavages in nasopharyngeal epithelial cells: implications in chromosome rearrangement

BACKGROUND

Chronic rhinosinusitis (CRS) increases the risk of developing nasopharyngeal carcinoma (NPC) while nasopharyngeal reflux is known to be one of the major aetiological factors of CRS. Bile acid (BA), the component of gastric duodenal contents, has been recognised as a carcinogen. BA-induced apoptosis was suggested to be involved in human malignancies. Cells have the potential and tendency to survive apoptosis. However, cells that evade apoptosis upon erroneous DNA repair may carry chromosome rearrangements. Apoptotic nuclease, caspase-activated deoxyribonuclease (CAD) has been implicated in mediating translocation in leukaemia. We hypothesised that BA-induced apoptosis may cause chromosome breaks mediated by CAD leading to chromosome rearrangement in NPC. This study targeted the AF9 gene located at 9p22 because 9p22 is one of the most common deletion sites in NPC.

METHODS

We tested the ability of BA at neutral and acidic pH in inducing phosphatidylserine (PS) externalisation, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP) disruption, and caspase 3/7 activity in normal nasopharyngeal epithelial (NP69) and NPC (TWO4) cells. Inverse-PCR (IPCR) was employed to detect AF9 gene cleavages. To investigate the role of CAD in mediating these cleavages, caspase inhibition was performed. IPCR bands representing AF9 cleaved fragments were sequenced.

RESULTS

BA-treated cells showed higher levels of PS externalisation, ROS production, MMP loss and caspase 3/7 activity than untreated control cells. The effect of BA in the induction of these intracellular events was enhanced by acid. BA at neutral and acidic pH also induced significant cleavage of the AF9 gene. These BA-induced gene cleavages were inhibited by Z-DEVD-FMK, a caspase-3 inhibitor. Intriguingly, a few chromosome breaks were identified within the AF9 region that was previously reported to participate in reciprocal translocation between the mixed lineage leukaemia (MLL) and AF9 genes in an acute lymphoblastic leukaemia (ALL) patient.

CONCLUSIONS

These findings suggest a role for BA-induced apoptosis in mediating chromosome rearrangements in NPC. In addition, CAD may be a key player in chromosome cleavages mediated by BA-induced apoptosis. Persistent exposure of sinonasal tract to gastric duodenal refluxate may increase genomic instability in surviving cells.

Preventive effect of oral hangeshashinto (TJ-14) on the development of reflux-induced esophageal cancer

BACKGROUND

Prostaglandin E2 is one of the potential products that promotes development of tumors and also is a strong inducer of M2 phenotype macrophages, which contribute to tumor development in the immunosuppressed microenvironment. Hangeshashinto (TJ-14), a Japanese traditional medicine (Kampo medicine), has been reported to be effective in preventing chemotherapy-induced oral mucositis through the reduction of prostaglandin E2. We previously developed a surgical rat reflux model of esophageal cancer and used this well-established animal model to investigate the action of TJ-14 in preventing esophageal cancer. We also assessed the effect of TJ-14 on the downregulation of prostaglandin E2 production, utilizing esophageal squamous cell carcinoma cell line exposed to bile acid.

METHODS

An end-to-side esophagojejunostomy was performed for the reflux model. A daily oral diet was subsequently administered, consisting of either diet-incorporated TJ-14 or standard diet as a control group. The rats were killed at 40 weeks after surgery. The incidence of esophageal cancer, Barrett's metaplasia, and proliferative hyperplasia were assessed histologically. CD163, a M2 phenotype macrophage marker, was assessed with immunohistochemistry. Prostaglandin E2 enzyme immunoassay and lactate dehydrogenase assay were performed on chenodeoxycholic acid or gastroesophageal reflux contents exposed to esophageal squamous cell carcinoma cell line.

RESULTS

Sixty-seven percent of the controls (n = 12) developed esophageal cancer, but animals that received TJ-14 (n = 10) had a cancer incidence of 10% (P=.007). Barrett's metaplasia was found in 83% of the rats in the control group and 50% of the rats in the TJ-14 indicating a protective tendency of TJ-14 (P=.095). All of the rats developed proliferative hyperplasia. The number of M2 phenotype macrophage were significantly decreased in the TJ-14 group compared to the control group in both Barrett's metaplasia and esophageal cancer lesions. TJ-14 inhibited chenodeoxycholic acid or gastroesophageal reflux content-induced prostaglandin E2 production in esophageal squamous cell carcinoma cell.

CONCLUSION

TJ-14 reduced the incidence of reflux-induced esophageal cancer and the infiltration of M2 macrophages in a surgical rat model or suppressed prostaglandin E2 production in esophageal squamous cell carcinoma cell. Further investigation is required regarding the potential clinical use of TJ-14 as an esophageal cancer chemopreventive agent.

In Vivo Short-Term Topical Application of BAY 11-7082 Prevents the Acidic Bile-Induced mRNA and miRNA Oncogenic Phenotypes in Exposed Murine Hypopharyngeal Mucosa

PURPOSE: Bile-containing gastroesophageal reflux may promote cancer at extraesophageal sites. Acidic bile can accelerate NF-κB activation and molecular events, linked to premalignant changes in murine hypopharyngeal mucosa (HM). We hypothesize that short-term in vivo topical application of NF-κB inhibitor BAY 11-7082 can prevent acidic bile–induced early preneoplastic molecular events, suggesting its potential role in disease prevention. EXPERIMENTAL DESIGN: We topically exposed HM (C57Bl/6j wild-type) to a mixture of bile acids at pH 3.0 with and without BAY 11-7082 3 times/day for 7 days. We used immunofluorescence, Western blotting, immunohistochemistry, quantitative polymerase chain reaction, and polymerase chain reaction microarrays to identify NF-κB activation and its associated oncogenic mRNA and miRNA phenotypes, in murine hypopharyngeal cells in vitro and in murine HM in vivo. RESULTS: Short-term exposure of HM to acidic bile is a potent stimulus accelerating the expression of NF-κB signaling (70 out of 84 genes) and oncogenic molecules. Topical application of BAY 11-7082 sufficiently blocks the effect of acidic bile. BAY 11-7082 eliminates NF-κB activation in regenerating basal cells of acidic bile–treated HM and prevents overexpression of molecules central to head and neck cancer, including bcl-2, STAT3, EGFR, TNF-α, and WNT5A. NF-κB inhibitor reverses the upregulated “oncomirs” miR-155 and miR-192 and the downregulated “tumor suppressors” miR-451a and miR-375 phenotypes in HM affected by acidic bile. CONCLUSION: There is novel evidence that acidic bile–induced NF-κB–related oncogenic mRNA and miRNA phenotypes are generated after short-term 7-day mucosal exposure and that topical mucosal application of BAY 11-7082 can prevent the acidic bile–induced molecular alterations associated with unregulated cell growth and proliferation of hypopharyngeal cells.

From Heartburn to Barrett's Esophagus, and Beyond

BACKGROUND

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the USA, and its prevalence is increasing worldwide. About 10-15% of patients with GERD will develop Barrett's esophagus (BE).

AIMS

The aims of this study were to review the available evidence of the pathophysiology of BE and the role of anti-reflux surgery in the treatment of this disease.

RESULTS

The transformation of the squamous epithelium into columnar epithelium with goblet cells is due to the chronic injury produced by repeated reflux episodes. It involves genetic mutations that in some patients may lead to high-grade dysplasia and cancer. There is no strong evidence that anti-reflux surgery is associated with resolution or improvement in BE, and its indications should be the same as for other GERD patients without BE.

CONCLUSIONS

Patients with BE without dysplasia require endoscopic surveillance, while those with low- or high-grade dysplasia should have consideration of endoscopic eradication therapy followed by surveillance. New endoscopic treatment modalities are being developed, which hold the promise to improve the management of patients with BE.

Inhibition of NF-κB prevents the acidic bile-induced oncogenic mRNA phenotype, in human hypopharyngeal cells

Bile-containing gastro-duodenal reflux has been clinically considered an independent risk factor in hypopharyngeal carcinogenesis. We recently showed that the chronic effect of acidic bile, at pH 4.0, selectively induces NF-κB activation and accelerates the transcriptional levels of genes, linked to head and neck cancer, in normal hypopharyngeal epithelial cells. Here, we hypothesize that NF-κB inhibition is capable of preventing the acidic bile-induced and cancer-related mRNA phenotype, in treated normal human hypopharyngeal cells. In this setting we used BAY 11-7082, a specific and well documented pharmacologic inhibitor of NF-κB, and we observed that BAY 11-7082 effectively inhibits the acidic bile-induced gene expression profiling of the NF-κB signaling pathway (down-regulation of 72 out of 84 analyzed genes). NF-κB inhibition significantly prevents the acidic bile-induced transcriptional activation of NF-κB transcriptional factors, RELA (p65) and c-REL, as well as genes related to and commonly found in established HNSCC cell lines. These include anti-apoptotic bcl-2, oncogenic STAT3, EGFR, ∆Np63, TNF-α and WNT5A, as well as cytokines IL-1β and IL-6. Our findings are consistent with our hypothesis demonstrating that NF-κB inhibition effectively prevents the acidic bile-induced cancer-related mRNA phenotype in normal human hypopharyngeal epithelial cells supporting an understanding that NF-κB may be a critical link between acidic bile and early preneoplastic events in this setting.

Postgastrectomy Syndromes and Nutritional Considerations Following Gastric Surgery

Postgastrectomy syndromes result from altered form and function of the stomach. Gastrectomy disrupts reservoir capacity, mechanical digestion and gastric emptying. Early recognition of symptoms with prompt evaluation and treatment is essential. Many syndromes resolve with minimal intervention or dietary modifications. Re-operation is not common but often warranted for afferent and efferent loop syndromes and bile reflux gastritis. Preoperative nutritional assessment and treatment of common vitamin and mineral deficiencies after gastrectomy can reduce the incidence of chronic complications. An integrated team approach to risk assessment, patient education, and postoperative management is critical to optimal care of patients with gastric cancer.

Effects of bile acids on human airway epithelial cells: implications for aerodigestive diseases

Gastro-oesophageal reflux and aspiration have been associated with chronic and end-stage lung disease and with allograft injury following lung transplantation. This raises the possibility that bile acids may cause lung injury by damaging airway epithelium. The aim of this study was to investigate the effect of bile acid challenge using the immortalised human bronchial epithelial cell line (BEAS-2B). The immortalised human bronchial epithelial cell line (BEAS-2B) was cultured. A 48-h challenge evaluated the effect of individual primary and secondary bile acids. Post-challenge concentrations of interleukin (IL)-8, IL-6 and granulocyte-macrophage colony-stimulating factor were measured using commercial ELISA kits. The viability of the BEAS-2B cells was measured using CellTiter-Blue and MTT assays. Lithocholic acid, deoxycholic acid, chenodeoxycholic acid and cholic acid were successfully used to stimulate cultured BEAS-2B cells at different concentrations. A concentration of lithocholic acid above 10 μmol·L-1 causes cell death, whereas deoxycholic acid, chenodeoxycholic acid and cholic acid above 30 μmol·L-1 was required for cell death. Challenge with bile acids at physiological levels also led to a significant increase in the release of IL-8 and IL6 from BEAS-2B. Aspiration of bile acids could potentially cause cell damage, cell death and inflammation in vivo. This is relevant to an integrated gastrointestinal and lung physiological paradigm of chronic lung disease, where reflux and aspiration are described in both chronic lung diseases and allograft injury.

Gastro-duodenal fluid induced nuclear factor-κappaB activation and early pre-malignant alterations in murine hypopharyngeal mucosa

We recently described the role of gastro-duodenal fluids (GDFs) in generating changes consistent with hypopharyngeal neoplasia through activation of NF-κB pathway, using an in vitro model of human hypopharyngeal normal keratinocytes. Here, we further provide evidence that gastro-duodenal reflux is a risk factor for early pre-malignant alterations in hypopharyngeal mucosa (HM) related to an activated NF-κB oncogenic pathway, using both an in vitro and a novel in vivo model of C57Bl/6J mice. Histological, immunohistochemical and automated quantitative analysis documents significant NF-κB activation and early pre-malignant alterations in HM topically exposed to GDFs, compared to acid alone and other controls. Early pre-malignant histologic lesions exhibited increased Ki67, CK14 and ΔNp63, cell proliferation markers, changes of cell adhesion molecules, E-Cadherin and β-catenin, and STAT3 activation. The in vivo effect of NF-κB activation is positively correlated with p-STAT3, Ki67, CK14 or β-catenin expression, while GDFs induce significant transcriptional activation of RELA(p65), bcl-2, TNF-α, STAT3, EGFR and wnt5A, in vivo. Our in vivo model demonstrates selectively activated NF-κB in response to topically administrated GDFs, leading to early pre-malignant events in HM.

Gastroesophageal reflux disease and Barrett's esophagus after laparoscopic sleeve gastrectomy: a possible, underestimated long-term complication

BACKGROUND

Morbidly obese patients are affected by gastroesophageal reflux disease (GERD) and hiatal hernia (HH) more frequently than lean patients. Because of conflicting results, the indication to sleeve gastrectomy (SG) in patients with GERD is still debated.

OBJECTIVES

To evaluate the incidence of GERD on the basis of clinical, endoscopic, and histologic data in patients undergoing SG.

SETTINGS

University hospital, Rome, Italy.

METHODS

From July 2007 to January 2010, 162 patients underwent primary SG. Preoperatively all patients underwent visual analogue scale (VAS) evaluation of GERD symptoms, proton pump inhibitors (PPIs) consumption recording, and esophagogastroduodenoscopy (EGD). Stomach resection started 6 cm from pylorus on a 48Fr bougie. Staple line was reinforced by an oversewing suture. A postoperative clinical control with VAS evaluation, PPI consumption, and EGD was proposed to all patients. Three patients were excluded because of the occurrence of major postoperative complications.

RESULTS

A total of 110 patients accepted to take part in the study (follow-up rate: 69.1%). At a mean 58 months of follow-up, incidence of GERD symptoms, VAS mean score, and PPI intake significantly increased compared with preoperative values (68.1% versus 33.6%: P<.0001; 3 versus 1.8: P = .018; 57.2% versus 19.1%: P<.0001) At EGD, an upward migration of the "Z" line and a biliary-like esophageal reflux was found in 73.6% and 74.5% of cases, respectively. A significant increase in the incidence and in the severity of erosive esophagitis (EE) was evidenced, whereas nondysplastic Barrett's esophagus (BE) was newly diagnosed in 19 patients (17.2%). No significant correlations were found between GERD symptoms and endoscopic findings.

CONCLUSION

In the present series the incidence of EE and of BE in SG patients was considerably higher than that reported in the current literature, and it was not related to GERD symptoms. Endoscopic surveillance after SG should be advocated irrespective of the presence of GERD symptoms.

The tumor microenvironment in esophageal cancer

Esophageal cancer is a deadly disease, ranking sixth among all cancers in mortality. Despite incremental advances in diagnostics and therapeutics, esophageal cancer still carries a poor prognosis, and thus there remains a need to elucidate the molecular mechanisms underlying this disease. There is accumulating evidence that a comprehensive understanding of the molecular composition of esophageal cancer requires attention to not only tumor cells but also the tumor microenvironment, which contains diverse cell populations, signaling factors, and structural molecules that interact with tumor cells and support all stages of tumorigenesis. In esophageal cancer, environmental exposures can trigger chronic inflammation, which leads to constitutive activation of pro-inflammatory signaling pathways that promote survival and proliferation. Anti-tumor immunity is attenuated by cell populations such as myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), as well as immune checkpoints like programmed death-1 (PD-1). Other immune cells such as tumor-associated macrophages can have other pro-tumorigenic functions, including the induction of angiogenesis and tumor cell invasion. Cancer-associated fibroblasts secrete growth factors and alter the extracellular matrix (ECM) to create a tumor niche and enhance tumor cell migration and metastasis. Further study of how these TME components relate to the different stages of tumor progression in each esophageal cancer subtype will lead to development of novel and specific TME-targeting therapeutic strategies, which offer considerable potential especially in the setting of combination therapy.

A Single Institutions First 100 Patients Undergoing Laparoscopic Anti-Reflux Fundoplications: Where are They 20 Years Later?

Although anti-reflux surgery has been used liberally over the past decades for the treatment of gastroesophageal reflux disease (GERD), few studies report follow-up after 10 years. This study was undertaken to report follow-up on 100 consecutive GERD patients up to 22 years after utilizing a laparoscopic fundoplication. Hundred consecutive patients undergoing laparoscopic fundoplication for GERD were prospectively followed beginning in 1992. The frequency and severity of symptoms before and after laparoscopic fundoplication were scored on a Likert scale (1 = never/none to 10 = always/very bothersome). Median data are reported. Of the 100 patients who underwent laparoscopic fundoplication for their GERD, nine were reoperations. Twenty-six patients are deceased on average 11 years after their fundoplications. Seventy-four patients are alive, with 27 patients, actively followed for 19 years after their fundoplications. At most recent follow-up, patients experienced long-term amelioration of symptom frequency and severity after fundoplication (e.g., heartburn frequency = 8–2, severity = 8–1; P < 0.01 for each). Eighty-four per cent of patients rated their symptom frequency as less than once per month. Eighty-eight per cent of patients were satisfied with their postoperative results, and 95 per cent of patients confirmed they would have the operation again knowing what they know now. Long-term follow-up documents high patient satisfaction and durable symptomatic relief up to two decades after laparoscopic fundoplication for GERD. Patients should seek this operation not only for symptomatic relief, but to mitigate the deleterious effects of long-term acid exposure and anti-acid therapy.

Engineering Stent Based Delivery System for Esophageal Cancer Using Docetaxel

Esophageal cancer patients are often diagnosed as "advanced" cases. These patients are subjected to palliative stenting using self-expanding metallic stents (SEMS) to maintain oral alimentation. Unfortunately, SEMS get reoccluded due to tumor growth, in and over the stent struts. To investigate potential solutions to this problem, docetaxel (DTX) delivery films were prepared using PurSil AL 20 (PUS), which can be used as a covering material for the SEMS. Drug-polymer miscibility and interactions were studied. Bilayer films were prepared by adhering the blank film to the DTX loaded film in order to maintain the unidirectional delivery to the esophagus. In vitro release and the local DTX delivery were studied using in vitro permeation experiments. It was found that DTX and PUS were physically and chemically compatible. The bilayer films exhibited sustained release (>30 days) and minimal DTX permeation through esophageal tissues in vitro. The rate-determining step for the DTX delivery was calculated. It was found that >0.9 fraction of rate control lies with the esophageal tissues, suggesting that DTX delivery can be sustained for longer periods compared to the in vitro release observed. Thus, the bilayer films can be developed as a localized sustained delivery system in combination with the stent.

Endoscopic Ex Vivo Evaluation of Bile Concentrations by Narrow Band Imaging: A Pilot Study

Background. Bile juice plays a major role in duodenogastroesophageal reflux (DGERD). Several devices to directly measure the bile concentration have been proposed. We aimed to ex-vivo evaluate the bile concentration by narrow band imaging (NBI). Method. From six surgical cholecystectomies, the content of the gallbladders was aspirated and the total biliary acid (TBA) concentration was evaluated. 2 mL was employed for serial twofold dilutions. Each dilution was scoped. Images on white light (WL) and NBI were captured and grouped accordingly to NBI-appearance and TBA-concentration. Results. Nondiluted bile had a TBA-concentration of 61965 ± 32989 μmol/L. Final dilution (1 : 4096) had 1.16 μmol/L. NBI and correspondent WL images were grouped into seven groups, and an NBI/Bile scale was created. Conclusion. The scale showed that not only NBI scale but also white light scale could be useful to predict the bile concentration. This initial study shows that NBI has a potential role in the detection of DGERD and further investigation is warranted to distinguish the presence and the concentration of bile, especially at very low TBA concentrations.

Surgical Management of Barrett's Esophagus

Patients with gastroesophageal reflux disease and Barrett's esophagus can be a management challenge for the treating physician or surgeon. The goals of therapy include relief of reflux symptoms, induction of histologic regression, and prevention of progression of intestinal metaplasia to dysplasia or invasive carcinoma. Antireflux surgery is effective at achieving these end points, although ongoing follow-up and endoscopic surveillance are essential. In cases of dysplasia or early esophageal neoplasia associated with Barrett's esophagus, endoscopic resection and ablation have supplanted esophagectomy as the standard of care in most cases. Esophageal resection continues to have a role, however, in a minority of appropriately selected candidates.

Acidified bile acids increase hTERT expression via c-myc activation in human gastric cancer cells

Human telomerase reverse transcriptase (hTERT) is upregulated in most cancer cell types as well in immortalized cells. The underlying mechanism for such upregulation, however, remains largely unknown. We report here that bile acids under acidified media increase hTERT expression via c-myc activation in primary human gastric cancer cell lines. Human gastric cancer MKN28, MGC803 and SGC7901 cells were treated with 100 µM deoxycholic acid (DCA) or chenodeoxycholic acid (CDCA) with or without acidified media in the presence or absence of the c-myc inhibitor 10058-F4 for 24 h. hTERT and c-myc protein levels were determined by western blot analysis. hTERT and c-myc mRNA levels were determined by RT-PCR. The promoter activities of hTERT and c-myc transcription were determined using promoter reporter luciferase assays for both. Telomerase enzyme activity was analyzed by stretch PCR. hTERT mRNA and protein levels were significantly increased by bile acids in acidified media and were accompanied with enhanced telomerase activity. No changes were found at a pH of 7.0 or with acidified media alone. Similarly, the mRNA and protein levels of c-myc were also increased by bile acids in acidified media but not at a pH of 7.0 or with acidified media alone. Importantly, pharmacologic inhibition of c-myc using 10058-F4 prevented hTERT induction by DCA or CDCA in gastric cancer cells under acidic conditions. Bile acids (DCA and CDCA) under acidic conditions increased hTERT expression in human gastric cancer cells by activation of c-myc transcription. This suggests that acidified bile acids may promote tumorigenesis and affect cell ageing via telomerase activation.

"Mini" gastric bypass: systematic review of a controversial procedure

Mini gastric bypass is being explored by many bariatric surgeons as a standalone bariatric procedure. Several surgeons from different parts of the world have now published their extensive experience with this procedure. It appears to be an effective bariatric procedure with acceptable weight loss, co-morbidity resolution, and complication rates in the short and medium term. Its proponents claim that it is safer and easier than the gold standard Roux-en-Y gastric bypass. However, concerns with regard to symptomatic gastric or oesophageal biliary reflux requiring revisional surgery and long-term risk of gastric and oesophageal cancers persist. This paper reviews the published experience to date with this procedure and examines the surrounding controversy.

The impact of laparoscopic anti-reflux surgery in patients with Barrett's esophagus

BACKGROUND

Barrett's esophagus (BE) is a major risk factor for esophageal adenocarcinoma. It is believed that BE is caused by chronic gastro-esophageal reflux disease (GERD). Laparoscopic anti-reflux surgery (LARS) restores the competency of the cardia and may thereby change the natural course of BE. We studied the impact of LARS on the histological profile of BE and on the control of GERD.

METHODS

We identified all patients with BE who underwent LARS from 1994 to 2007 and contacted them to assess post-operative GERD symptoms via questionnaire. Endoscopy findings, histology, 24 hour pH monitoring, and manometry were also collected using our prospectively maintained database. Histological regression was defined as either loss of dysplasia or disappearance of BE.

RESULTS

Two hundred and fifteen patients met the initial inclusion criteria; in 82 of them histology from post-operative endoscopy was available for review. Endoscopy was performed a median of 8 years (range, 1-16 years) after surgery. Regression of BE occurred in 18 (22%) patients while in 6 (7%) BE progressed to dysplasia or cancer. Thirty-six (43%) patients underwent pre- and post-operative manometry. The median lower esophageal sphincter pressure increased from 9 to 17 mmHg in these patients. Thirty-four (41%) patients underwent pre- and post-operative pH studies. The median DeMeester score decreased from 54 to 9. Sixty-seven (82%) of 82 patients completed the post-operative questionnaire; 86% of these patients reported improvement in heartburn and regurgitation.

CONCLUSIONS

LARS was associated with both physiologic and symptomatic control of GERD in patients with BE. LARS resulted in regression of BE in 22% of patients and progression in 7%. Thus, continued surveillance of Barrett's is needed after LARS.

Effects of bile acids on cyclooxygenase-2 expression in a rat model of duodenoesophageal anastomosis

AIM: To examine the expression of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) in rat esophageal lesions induced by reflux of duodenal contents.

METHODS: Thirty 8-week-old male Wistar rats were exposed to duodenal content esophageal reflux. All animals underwent an esophagoduodenal anastomosis (EDA) with total gastrectomy to elicit chronic esophagitis. In ten rats sham operations with only a midline laparotomy were performed (Control). The rats were sacrificed at the 40^th week, their esophagi were taken for hematoxylin and eosin staining and for examination of expression of COX2, PGE2, and proliferating cell nuclear antigen (PCNA), and total bile acids in the esophageal lumen was measured.

RESULTS: After 40 wk of reflux, columnar dysplasia, squamous cell carcinoma and adenocarcinoma were observed. Total bile acids in the esophageal lumen were significantly increased in the EDA group compared with the sham operated rats. PCNA labelling index and esophageal tissue PGE2 levels were higher in dysplastic and cancer tissues than in control tissues. Overexpression of COX2 was observed in dysplastic and cancer tissues.

CONCLUSION: Reflux of duodenal contents induces COX2 expression and increases prostaglandin synthesis in dysplastic and cancer tissues. This result suggests a possible mechanism by which bile acids promote esophageal cancer.