Influence of pancreatic and biliary reflux on the development of esophageal carcinoma

Diffuse Esophageal Hyperkeratosis: A Rare Case Presentation

Diffuse esophageal hyperkeratosis (DEH) is a very intriguing and impressive mucosal finding that is quite easily identified on endoscopy and histology. A distinction must be made between microscopic/focal hyperkeratosis and endoscopically visible DEH. Microscopic hyperkeratosis is not uncommon in histological studies, while diffuse hyperkeratosis is seen very rarely. Over the past century, only a handful of cases have been reported. The endoscopic appearance of hyperkeratosis is of thick, white, piled-up mucosa. On histology, there is a prominent thickening of the stratum corneum, the squamous cells are anuclear, and there is no hyperplasia of the squamous epithelium. These histological characteristics distinguish benign orthokeratotic hyperkeratosis from other premalignant entities such as parakeratosis or leukoplakia where hyperplastic squamous cells retain pyknotic nuclei, lack keratohyalin granules, and also lack complete keratinization in superficial epithelial cells. The clinical presentation of hyperkeratosis includes gastroesophageal reflux, hiatal hernia, and associated symptoms. Our case highlights a very rare endoscopic finding associated with a common clinical presentation. The nearly 10-year follow-up reinforces the benign nature of ortho-hyperkeratosis and our report underscores the features that distinguish DEH from premalignant conditions. It merits additional research into factors that lead to hyperkeratinization of the esophageal mucosa as opposed to the more common columnar metaplasia. The concomitant presence of Barrett's esophagus in some patients is even more intriguing. Animal models with variable pH and content of the refluxate may shed light on the role played by duodenogastric/non-acid reflux in this condition. Larger, prospective, multicenter studies may provide the answers.

Intestinal Metaplasia in the Esophageal Remnant Is Rare After Ivor Lewis Esophagectomy

BACKGROUND

Most patients undergoing esophagectomy will experience intermittent reflux of gastric and biliary content into the remnant esophagus postoperatively. The incidence of new or recurrent intestinal metaplasia following chemoradiation and surgery has not been well-described. Furthermore, post-resection guidelines do not exist regarding surveillance for metaplasia in the esophageal remnant.

METHODS

Patients undergoing Ivor Lewis esophagectomy after concurrent chemoradiation for a diagnosis of esophageal adenocarcinoma from 2006 to 2018 were identified. Pathology records were reviewed for the presence of intestinal metaplasia on pretreatment biopsies, surgical specimen, or post-resection biopsies.

RESULTS

In total, 619 patients met inclusion criteria, including 267 (43%) who had intestinal metaplasia noted either prior to or at the time of esophagectomy. The median duration of metaplastic disease prior to resection was 4.4 months. During a median follow-up time of 28 months (interquartile range, 12-60), intestinal metaplasia was noted in the remnant esophagus in 12 (2%) patients, 7 of whom had a prior history of metaplasia. Local recurrence of adenocarcinoma was also uncommon, and occurred in 37/577 (6%) of patients with complete resections, with similar event rates among those with and without a prior history of metaplasia (14/249 [6%] vs. 23/328 [7%], p = 0.614).

CONCLUSIONS

Our findings suggest that despite several factors predisposing to mucosal damage following esophagectomy, occurrence of new intestinal metaplasia after trimodality therapy in our patient population appears to be rare, even among patient with a previous history of this pathologic finding, which may have significant implications for surveillance and cost-savings after resection.

Oesophageal motor disorders and oesophageal endoscopic involvement in patients with systemic sclerosis: a systematic association?

INTRODUCTION

Although oesophageal motor disorders (OMDs) are frequent in systemic sclerosis (SSc), the frequency of associated endoscopic lesions is unknown. We aimed at assessing the presence of endoscopic lesions in SSc patients with OMD. The secondary objective was to identify the clinical and serological profile of such patients.

METHODS

This retrospective study included SSc patients suffering from OMD diagnosed by oesophageal high-resolution manometry (OHRM) and with recent upper gastro-intestinal endoscopy (UGIE). Clinical data collected were age, gender, body mass index, SSc disease duration, tobacco, SSc cutaneous type, non-digestive SSc visceral disorders, oesophageal symptoms, serological profile (autoantibodies), proton pump inhibitor use, time between SSc diagnosis and UGIE.

RESULTS

53 selected patients from 210 SSc patients investigated by OHRM in our department were included. Among these patients, 25 (47.2%) had endoscopic lesions: 18 (34.6%) had oesophagitis and 7 (13.5%) had Barrett's oesophagus. The only two parameters significantly associated with endoscopic lesions were a shorter disease duration (6 vs. 11 years; p = .002) and a shorter delay between SSc diagnosis and UGIE (3 vs. 8.5 years; p = .002). No other clinical or biological parameters could help identify the patients at risk of endoscopic lesion.

CONCLUSION

In our study, only a shorter disease duration and a shorter delay between SSc diagnosis and UGIE were significantly associated with the presence of endoscopic lesions in patients with OMD, but no other parameters were identified. This study highlights the need to perform UGIE in SSc patients with OMD whatever their clinical symptoms.

Do proton pump inhibitors prevent Barrett's esophagus progression to high-grade dysplasia and esophageal adenocarcinoma? An updated meta-analysis

PURPOSE

Previous research on the association between proton pump inhibitor (PPI) use and the risk of progression to high-grade dysplasia (HGD)/esophageal adenocarcinoma (EAC) in Barrett's Esophagus (BE) patients has generated inconsistent findings. This meta-analysis was performed to clarify the association.

METHODS

We performed a comprehensive search strategy to select relevant studies up to September 2020. Heterogeneity was assessed using the I-squared statistic. Odds ratios (OR) and 95% confidence intervals (CI) were calculated through either fixed-effects or random-effects model. Duration-response was also performed to assess the gain effects of different PPI intake duration. Sensitivity analysis, subgroup analyses, and tests for publication bias or other small-study effects were conducted.

RESULTS

Twelve studies with 155,769 subjects were included. The PPI use was associated with the reduced risk of BE progression to HGD/EAC (OR = 0.47, 95% CI = 0.32-0.71). In the duration-response analysis, the estimated OR for decreased risk of HGD/EAC with PPI intake duration of 12 months was 0.81 (95% CI = 0.71-0.91). Sensitivity analysis suggested the results of this meta-analysis were stable. No publication bias was detected.

CONCLUSIONS

PPI use is associated with a decreased risk of HGD/EAC in patients with BE. For further investigation, that more well-designed studies are still needed to elucidate the protective effect of PPI usage on BE patients to prevent HGD/EAC.

Comparison of outcomes of pedicled jejunal and colonic conduit for esophageal reconstruction

BACKGROUND

At present, the gastric tube is the first choice for esophageal reconstruction after esophagectomy for various benign and malignant diseases. However, when the stomach is not available, a pedicled jejunum or colon is used to reconstruct the esophagus. The present study aimed to compare the postoperative outcomes and quality of life of patients receiving jejunal and colonic conduits.

METHODS

In the present retrospective study, the clinical data of 71 patients with esophageal carcinoma, who received jejunal reconstruction (jejunum group, n = 34) and colonic reconstruction (colon group, n = 37) from 2005 to 2015, were compared.

RESULTS

Compared with the colon group, the jejunum group had a lower incidence of postoperative anastomotic leakage, lesser duration of postoperative drainage, and faster recovery. Furthermore, the scores were better in the jejunum group than in the colon group, in terms of short-term overall quality of life, physical function and social relationships. Moreover, the jejunal group had a significantly lower frequency of pH < 4 simultaneous reflux time > 5 min (N45) and the longest reflux time (LT) at 24 weeks after surgery.

CONCLUSION

In esophageal cancer, when gastric tube construction is not feasible, a pedicled jejunum may be preferred over a colonic conduit due to lower incidence of acid reflux, anastomotic leakage and higher postoperative short-term quality of life, and rapid postoperative recovery.

Identification of candidate aberrantly methylated and differentially expressed genes in Esophageal squamous cell carcinoma

Aberrant methylated genes (DMGs) play an important role in the etiology and pathogenesis of esophageal squamous cell carcinoma (ESCC). In this study, we aimed to integrate three cohorts profile datasets to ascertain aberrant methylated-differentially expressed genes and pathways associated with ESCC by comprehensive bioinformatics analysis. We downloaded data of gene expression microarrays (GSE20347, GSE38129) and gene methylation microarrays (GSE52826) from the Gene Expression Omnibus (GEO) database. Aberrantly differentially expressed genes (DEGs) were obtained by GEO2R tool. The David database was then used to perform Gene ontology (GO) analysis and Kyoto Encyclopedia of Gene and Genome pathway enrichment analyses on selected genes. STRING and Cytoscape software were used to construct a protein-protein interaction (PPI) network, then the modules in the PPI networks were analyzed with MCODE and the hub genes chose from the PPI networks were verified by Oncomine and TCGA database. In total, 291 hypomethylation-high expression genes and 168 hypermethylation-low expression genes were identified at the screening step, and finally found six mostly changed hub genes including KIF14, CDK1, AURKA, LCN2, TGM1, and DSG1. Pathway analysis indicated that aberrantly methylated DEGs mainly associated with the P13K-AKT signaling, cAMP signaling and cell cycle process. After validation in multiple databases, most hub genes remained significant. Patients with high expression of AURKA were associated with shorter overall survival. To summarize, we have identified six feasible aberrant methylated-differentially expressed genes and pathways in ESCC by bioinformatics analysis, potentially providing valuable information for the molecular mechanisms of ESCC. Our data combined the analysis of gene expression profiling microarrays and gene methylation profiling microarrays, simultaneously, and in this way, it can shed a light for screening and diagnosis of ESCC in future.

Preclinical models for the study of Barrett's carcinogenesis

Barrett's esophagus (BE) is clinically significant, as it is the only known precursor lesion for esophageal adenocarcinoma. To develop improved therapies for the treatment of BE, a greater understanding of the disease process at the molecular genetic level is needed. However, achieving a greater understanding will require improved preclinical models so that the disease process can be more closely studied and novel therapies can be tested. Our concise review highlights progress in the development of preclinical models for the study of BE and identifies the most suitable model in which to test novel therapies.

Clinical outcome of using gastric remnant or jejunum or colon conduit in surgery for esophageal carcinoma with previous gastrectomy

BACKGROUND

For esophageal carcinoma patients with early gastrectomy, individualized surgical plans-including selection of replacement conduit and operation route based on patient's new lesion and surgical history-can achieve the desired therapeutic effect and improve postoperative life quality. We investigated the outcomes at our institution.

METHODS

The clinical data of 42 esophageal carcinoma patients with early gastrectomy were analyzed retrospectively.

RESULTS

Esophagectomy was performed combining replacement with remnant stomach in 16 patients, jejunum in 17, and colon in 9. Esophagectomy combining replacement with gastric remnant got advantages of shorter operation time and less bleeding over that of replacement with jejunum or colon. Gastric remnant group scored higher on the QLQ-C30 questionnaire than jejunum or colon group with respect to overall quality of life, physical function, and social relationships. In QLQ-OES18 questionnaire, the scores of appetite recovery and reflux mitigation were more favorable in remnant stomach group than those in jejunum or colon group. Survival analysis showed no significant difference in survival rate among the patients undergoing replacement with gastric remnant, jejunum, or colon.

CONCLUSIONS

For esophageal carcinoma patients with early gastrectomy, esophagus-gastric remnant anastomosis possesses advantages of shorter operation time, less surgical trauma, and greater life quality after surgery.

Continuous taurocholic acid exposure promotes esophageal squamous cell carcinoma progression due to reduced cell loss resulting from enhanced vascular development

BACKGROUND

Refluxogenic effects of smoking and alcohol abuse may be related to the risk of esophageal squamous cell carcinoma (ESCC). The present study attempts to clarify the effects of continuous taurocholic acid (TCA) exposure, which is neither mutagenic nor genotoxic, on ESCC progression.

METHODS

A squamous carcinoma cell line (ESCC-DR) was established from a tumor induced in a rat model of gastroduodenal reflux. ESCC-DR cells were incubated with 2 mM TCA for ≥2 months. The effects of continuous TCA exposure were evaluated in vitro on cell morphology, growth, and invasion and in vivo on xenograft tumor growth in nude mice. Moreover, the mean level of secreted transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF) proteins in cell culture supernatants and mRNA synthesis of TGF-β1 and VEGF-A of ESCC cells were measured. The angiogenic potential was further examined by a migration assay using human umbilical vein endothelial cells (HUVECs).

RESULTS

Continuous TCA exposure induced marked formation of filopodia in vitro. Expression levels of angiogenic factors were significantly higher in the cells treated with TCA than in control cells. Tumor xenografts derived from cells pre-exposed to TCA were larger and more vascularized than those derived from control cells. In addition, TCA exposure increased HUVEC migration.

CONCLUSION

Continuous TCA exposure enhanced ESCC progression due to reduced cell loss in vivo. Cell loss was inhibited by TCA-induced vascular endothelial cell migration, which was mediated by TGF-β1 and VEGF-A released from ESCC cells.

Radiological evaluation of the patency of duodenal-esophageal anastomosis during a long postoperative follow-up: effectiveness of an alkaline reflux model in rats

Background:

Performing experimental studies has played an important role in acquiring knowledge about esophageal carcinogenesis. In this context, the choice of a more reliable experimental model requires proof of its effectiveness in order to lend greater credibility to the results. The objective of this study was to evaluate the patency of duodenal-esophageal anastomosis during long-term postoperative follow-up in rats.

Methods:

This was an experimental study in which 45 female Wistar rats were used. A side-to-side anastomosis was performed, going from the anterior side of the esophagus to the second duodenal portion. A standardized radiological technique was used to carry out a contrasted radiological study of the esophagus, stomach, and duodenum during weeks 4, 12, 20, and 30 after surgery. Different contrast media were used, and the animals were divided into groups, ie, group 1 (100% barium sulfate), group 2 (50% barium sulfate), and group 3 (60% aqueous iodinated contrast media). Contrast radiographs were taken in each group at weeks 4, 12, 20, and 30 after the surgical procedure. The radiographic images were evaluated by two radiologists who were blinded regarding the contrast groups. Macroscopic evaluation of each animal was compared with the radiological findings.

Results:

Postoperative mortality was 13.33%. The remaining animals were divided into study groups. All the contrast radiological examinations showed evidence of the location of the esophagus, stomach, and proximal portion of the intestine, and demonstrated the laterolateral relationship of the distal esophagus and the duodenum in the epigastric region. Patency of the anastomosis was observed at each examination period. The different contrast media used were able to demonstrate this outcome shortly after the first phase of injection. Necropsies corroborated the radiological findings.

Conclusion:

Regardless of the contrast agent used, contrasted radiography revealed that side-to-side duodenal-esophageal anastomosis in rats allowed patent communication during long-term postoperative follow-up.

Effects of refluxate pH values on duodenogastroesophageal reflux-induced esophageal adenocarcinoma

AIM: To determine the effects of duodenogastric juice pH on the development of esophageal adenocarcinoma (EAC).

METHODS: An animal model of duodenogastroesophageal reflux was established using Sprague-Dawley (SD) rats undergoing esophagoduodenostomy (ED). The development of EAC was investigated in rats exposed to duodenogastric juice of different pH. The rats were divided into three groups: low-pH group (group A), high-pH group (group B) and a sham-operated group as a control (group C) (n = 30 rats in each group). The incidence of esophagitis, Barrett’s esophagus (BE), intestinal metaplasia with dysplasia and EAC was observed 40 wk after the treatment.

RESULTS: The incidence rate of esophagitis, BE, intestinal metaplasia with dysplasia and EAC was higher in groups A and B compared with the control group after 40 wk (P < 0.01), being 96% and 100% (P > 0.05), 88% and 82.4% (P > 0.05), 20% and 52.1% (P < 0.05), and 8% and 39% (P < 0.05), respectively.

CONCLUSION: Non-acidic refluxate increases the occurrence of intestinal metaplasia with dysplasia and EAC while the low-pH gastric juice exerts a protective effect in the presence of duodenal juice. The non-acid reflux is particularly important in the progression from BE to cancer. Therefore, control of duodenal reflux may be an important prophylaxis for EAC.

Serum pepsinogens and Helicobacter pylori in relation to the risk of esophageal squamous cell carcinoma in the alpha-tocopherol, beta-carotene cancer prevention study

BACKGROUND

Helicobacter pylori can induce gastric atrophy in humans, which in turn increases gastric cancer risk. Whether H. pylori and gastric atrophy also affect the risk of esophageal squamous cell carcinoma (ESCC), however, remains unresolved.

METHODS

We performed a nested case-control study within the prospective Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study to assess these relationships. The Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study is composed of 29,133 Finnish male smokers, ages 50 to 69 years, who were recruited during 1985-1988. Using baseline sera, we assessed H. pylori status (via immunoglobulin G antibodies against whole-cell and CagA antigens) and gastric atrophy status [via the biomarkers pepsinogen I (PGI) and pepsinogen II (PGII)] in 79 ESCC cases and 94 controls. Logistic regression with adjustment for age, date of blood draw, education, cigarette smoking, alcohol, body mass index, and fruit and vegetable intake was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

Gastric atrophy (PGI/PGII <4) was associated with ESCC (OR, 4.58; 95% CI, 2.00-10.48). There was no evidence for an association between H. pylori and ESCC (OR, 0.94; 95% CI, 0.40-2.24).

CONCLUSIONS

These results could be explained by misclassification of H. pylori status due to serologic amnesia, ESCC risk being dependent on the functional consequences or interactions of H. pylori rather than the infection per se, gastric atrophy having a different histogenesis in ESCC without being primarily dependent on H. pylori acquisition, or a lack of statistical power to detect an effect.

IMPACT

Validation of these results may warrant mechanistic studies to determine the route of association between gastric atrophy and ESCC.

Gastric surgery is not a risk factor for erosive esophagitis or Barrett's esophagus

OBJECTIVE

The role of gastric acid reflux is difficult to separate from that of pancreatic-biliary reflux in the pathogenesis of erosive esophagitis (EE) and Barrett's esophagus (BE). Gastric surgery patients provide a good model for both significant pancreatic-biliary reflux and marked gastric acid inhibition. We assessed the risk of EE and BE after distal gastrectomy in a case-controlled study.

MATERIAL AND METHODS

One hundred and sixty patients (121 men, 39 women; median age 68 years; range 32-86 years) with distal gastrectomies (Billroth-I) and 160 sex- and age-matched controls with intact stomachs were enrolled. The presence of EE and BE were diagnosed based on the Los Angeles Classification and the Prague C & M Criteria, respectively. A conditional logistic regression model with adjustments for potential confounding factors was used to assess the associations.

RESULTS

According to the multivariate analyses, patients with distal gastrectomies tended to have inverse associations with the risks of EE and BE, and the inverse association with the risk of BE reached a significant level.

CONCLUSIONS

Distal gastrectomy is not a risk factor for the development of EE and BE. This lack of a positive association between distal gastrectomy and EE and BE may suggest that pancreatic-biliary reflux with a limited amount of acid is not sufficient to damage the esophageal mucosa.

Surgical treatment and prognosis of esophageal cancer after distal gastrectomy

BACKGROUND

The purpose of the present study was to explore the clinicopathological characteristics and operative therapeutic efficacy of thoracic esophageal cancer after gastrectomy and compare with those without gastrectomy.

METHODS

From January 2000 to June 2007, 28 esophageal cancer patients with a history of distal gastrectomy underwent subtotal esophagectomy. Vascularized pedicle colonic conduit was most commonly used for esophageal substitution. Six hundred seventeen patients without a history of gastrectomy treated in the same period form the control group. After the operation, pathological characteristic, tumor staging, and survival statistics were analyzed.

RESULTS

Of those patients with esophageal cancer associated with gastric remnant, the majority were male. There was an average of 16.5 years for diagnosing esophageal cancer from the initial partial gastrectomy, 75% (21/28) of them were patients with Billroth I anastomosis. The proportion of lower-third tumors in patients after gastrectomy (12 of 28 patients, 43%) was significantly higher compared with that of the patients with intact stomachs (124 of 617 patients, 20%; P = 0.004). After surgical treatment, the overall 1-, 3-, and 5-year survival rates of gastrectomized and nongastrectomized patients were 100%, 35.00%, and 23.33% versus 98.93%, 59.42%, and 30.85% in stages I-II and 80.00%, 30.00%, and 0% versus 98.59%, 62.03%, and 21.03% in stages III-IV. The log rank test of equality of survival distribution for the gastrectomized vs nongastrectomized patients was not significant in stages I-II (P = 0.5692) but was significant in stages III-IV (P = 0.0166).

CONCLUSIONS

The patients with partial gastrectomy for more than 5 years, having upper gastrointestinal symptoms, should be considered having the risk of esophageal cancer associated with gastric remnant. For patients with a history of distal gastrectomy, a vascularized pedicle colonic conduit was most commonly used for esophageal substitution. Surgical efficacy was similar with the no-gastrectomy group in early stages I-II of esophageal cancer associated with gastric remnant but was lower compared with the no-gastrectomy group in stages III-IV. So, early diagnosis and an aggressive surgical approach may be crucial to achieve better outcomes for esophageal cancer patients with gastrectomy.

Os nitritos são importantes na gênese do adenocarcinoma associado ao esôfago de Barrett?

RACIONAL: O esôfago de Barrett é complicação do refluxo gastroesofágico e predispõe ao surgimento do adenocarcinoma, sendo que vários fatores têm sido relacionados à sua etiopatogenia. OBJETIVO: Analisar o modelo experimental de refluxo duodenogastroesofágico e a ingestão de solução de nitrito de sódio na gênese do adenocarcinoma associado ao esôfago de Barrett. MÉTODOS: Sessenta ratos machos Wistar foram divididos em quatro grupos, com 20 animais controles não operados (10 animais ingeriram somente água e 10 água mais solução de nitrito de sódio) e 40 animais submetidos à anastomose duodenogastroesofágica látero-lateral (20 animais ingeriram somente água e 20 animais ingeriram água mais solução de nitrito de sódio). A ocorrência de esofagite, metaplasia, displasia, esôfago de Barrett e adenocarcinoma associado foram analisados. A classificação de Viena para displasia e adenocarcinoma foi empregada na análise dos resultados. RESULTADOS: Após 42 semanas de observação, nos animais operados sem ingestão de nitritos o esôfago de Barrett foi registrado em 26,3% (5/19), enquanto no grupo operado associado à ingestão de nitritos, foi encontrado em 72,3% (13/18) dos animais, sendo que neste grupo também foi encontrado seis adenocarcinomas (33,3%). Nenhum animal não operado apresentou o esôfago de Barrett. As categorias 2, 3 e 5 da classificação de Viena somente foram encontradas nos animais operados que ingeriram nitrito de sódio (66,7%). CONCLUSÃO: A ingestão de nitrito de sódio associado ao refluxo duodenogastroesofágico têm importante participação na gênese do adenocarcinoma associado ao esôfago de Barrett.

Effect of Roux-en-Y surgery and medical intervention on Barrett's-type changes: an in vivo model

In animal models, mixed acid and bile reflux into lower esophagus induces histological changes comparable to Barrett's metaplasia (BM) and neoplasia. The aim of this study was to compare the effects of Roux-en-Y (REY) surgery and medical therapy on BM in animals before the development of neoplasia. Vagus preserving esophagojejunostomy operation was performed on Sprague-Dawley rats to achieve gastroduodenal reflux (GDR) into the esophagus in 30 animals. After 3 months, changes were reversed in 10 animals (Group REY) by REY operation, 10 animals (Group proton pump inhibitor [PPI]) were given PPI during the postoperative period, and 10 animals (Group GDR) did not have further intervention. At 4 months, histological examination of the lower esophagus was performed by an experienced pathologist. Physiological parameters were also analyzed in all animals preoperatively and at 4 months postoperatively. The length of columnar mucosa, degree of acute inflammation, degree of metaplasia, and composite BM score were significantly reduced by REY surgery compared with medical therapy and with control (columnar mucosa in cm [mean +/- standard error of the mean] Group REY 0.44 +/- 0.06, Group PPI 0.92 +/- 0.08, P < 0.001/Group GDR 1.17 +/- 0.31, P < 0.03). There was no neoplasia seen in any specimen. At 4 months, postoperatively controls Group REY surgery showed significantly more normalization of physiological parameters to preoperative levels than Group PPI (P < 0.05). REY surgery is potentially more beneficial than medical therapy in reversing the histological and biochemical changes of Barrett's esophagus due to GDR.

Clinical outcome of esophageal cancer after distal gastrectomy: a prospective study

OBJECTIVES

To investigate the clinicopathological characteristics and surgical outcome of thoracic esophageal cancer after gastrectomy, and compare with those without gastrectomy.

RESULT

Among 1411 esophageal cancer patients who underwent curative operation, 48 (3.4%) had a history of distal gastrectomy, the interval between gastrectomy and esophagectomy was significantly shorter in those gastrectomized for gastric cancer (11.5+/-8.2 years) than for peptic ulcer (24.6+/-9.2 years), the proportion of lower-third tumors and multiple esophageal cancer was significantly higher compared with that of the non-gastrectomized patients (50.0% vs. 33.1%, P=0.033; 14.6% vs. 5.3%, P=0.006, respectively), this increase was more pronounced after Billroth I vs. Billroth II gastrectomy. Pathologically, the esophageal cancers after gastrectomy frequently showed expansive growth pattern (39.6%), while those without gastrectomy dominantly showed infiltrative growth pattern (40.3%) (P=0.012), the coexisting lesions showed well-differentiated squamous cell carcinoma confined within the superficial mucosal layer. Compared with the non-gastrectomized patients, the operative time (311.2+/-86.0 vs. 263.7+/-84.9 min; P<0.001) was longer and blood loss (4.38+/-1.33 vs. 3.57+/-1.82 IU; P=0.003) was more, the postoperative hospital stay was significantly longer in gastrectomized patients (median 69 days vs. 40 days, P<0.001). The overall 1, 3, 5, 10-year survival of gastrectomized and non-gastrectomized patients were similar, and their cause-specific 5-year survival were 65% vs. 44% (P=0.992).

CONCLUSIONS

Gastrectomy (especially the Billroth I) precipitated subsequent chronic gastroesophageal reflux and induced the development of squamous dysplasia and carcinoma at multiple locations in the esophagus. Surgical treatment of the gastrectomized patients should be considered as a reliable therapeutic modality because of favorable prognoses.

Manometric study of the lower esophageal sphincter and esophagus in subtotal gastrectomy patients

There is controversy in the literature regarding the motor function behavior of the lower esophageal sphincter and esophagus following partial gastrectomy. We studied 26 patients with gastric adenocarcinoma of the distal corpus and/or antrum who underwent radical subtotal gastrectomy with Roux-en-Y reconstruction. There were 15 women (57.69%) and 11 men (42.31%) with a mean age of 57.2 years; 21 were White (80.8%) and five were of African descent (19.2%). Before the surgery and 3 months afterwards, every patient underwent manometric and endoscopic examinations. The lower esophageal sphincter showed reductions in mean respiratory pressure (19.41-15.59 mmHg, P= 0.02) and maximum expiratory pressure (8.13-5.54 mmHg, P= 0.02) without significant alteration in diaphragmatic crura pressure (32.92-30.64 mmHg, P= 0.37). An increase in peristaltic wave amplitude (91.43-124.86 mmHg, P < 0.01) and peristaltic wave conduction velocity (3.29 cm/s to 4.23 cm/s; P= 0.024) were detected in esophageal function. The presence of erosive esophagitis decreased from 10 (38.46%) patients to none (P= 0.002). We concluded that following surgery the lower esophageal sphincter function was impaired, through decreased pressure in the esophageal component without alteration in diaphragmatic crura pressure. On the other hand, there was significant increase in peristaltic wave amplitude and velocity, and improvement of the erosive esophagitis. The authors suggest that subtotal gastrectomy, with gastroesophageal junction preservation, and Roux-en-Y reconstruction should be the preferred operation for distal gastric cancer to minimize esophageal dysfunction and gastroesophageal reflux disease.

Neither Antioxidants nor COX-2 Inhibition Protect Against Esophageal Inflammation in an Experimental Model of Severe Reflux

BACKGROUND

Reflux-induced injury and oxidative stress result in esophageal inflammation and the potential for progression to intestinal metaplasia and adenocarcinoma. Proton-pump inhibitors represent the standard medical approach, but anti-inflammatories and antioxidants offer novel therapeutic possibilities.

MATERIALS AND METHODS

Six weeks after an esophagojejunostomy reflux procedure, female Wistar rats (n = 100) were randomized to receive either an antioxidant (vitamin C, 8 mg or 28 mg/day), a cyclooxygenase-2 (COX-2) inhibitor (rofecoxib, 1 mg/day), or no therapy. After sacrifice 16 weeks later, esophageal injury was scored using pathologic and image analysis scoring.

RESULTS

Esophagitis was present in all 63 animals completing the study and was severe in 27 (43%). No animal developed metaplasia or tumor. The extent of inflammation and esophageal ulceration were not significantly different between experimental groups.

CONCLUSIONS

In this model of reflux injury, antioxidants and COX-2 inhibitors failed to ameliorate the severe inflammation induced. Further experimental designs should evaluate these novel approaches in less severe experimental models.

Bone marrow progenitor cells contribute to esophageal regeneration and metaplasia in a rat model of Barrett's esophagus

Barrett's esophagus develops when refluxed gastric juice injures the esophageal squamous lining and the injury heals through a metaplastic process in which intestinal-type columnar cells replace squamous ones. The progenitor cell that gives rise to Barrett's metaplasia is not known, nor is it known why the condition is predisposed to malignancy. We studied the contribution of bone marrow stem cells to the development of Barrett's esophagus in an animal model. Twenty female rats were given a lethal dose of irradiation followed by tail vein injection of bone marrow cells from male rats. Ten days later, the female rats were randomly assigned to undergo either esophagojejunostomy, a procedure that causes reflux esophagitis with intestinal metaplasia, or a sham operation. The rats were killed at 8 weeks and serial sections of the snap-frozen esophagi were cut and mounted on slides. The first and last sections were used for histological evaluation and the intervening sections were immunostained for cytokeratin to identify epithelial cells and analyzed for Y chromosome by fluorescence in situ hybridization (FISH). Histological evaluation of the esophagi from rats that had esophagojejunostomy revealed ulcerative esophagitis and multiple areas of intestinal metaplasia. FISH analyses showed that some of the squamous epithelial cells and some of the columnar epithelial cells lining the glands of the intestinal metaplasia were positive for Y chromosome. These observations suggest that multi-potential progenitor cells of bone marrow origin contribute to esophageal regeneration and metaplasia in this rat model of Barrett's esophagus.

Activation of MUC1 mucin expression by bile acids in human esophageal adenocarcinomatous cells and tissues is mediated by the phosphatidylinositol 3-kinase

BACKGROUND

In esophageal adenocarcinoma, MUC1 mucin expression increases in early stages of the carcinogenetic sequence, during which bile reflux has been identified as a major carcinogen. However, no link between MUC1 overexpression and the presence of bile acids in the reflux has been established so far, and molecular mechanisms regulating MUC1 expression during esophageal carcinogenetic sequence are unknown. Our aim was to identify (1) the bile acids able to upregulate MUC1 expression in esophageal cancer cells and mucosal samples, (2) the regulatory regions in MUC1 promoter responsive to bile acids, and (3) the signaling pathway(s) involved in this regulation.

METHODS

MUC1 mRNA and mucin expression were studied by the means of real-time reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry, both in the human esophageal OE33 adenocarcinoma cell line and in an ex vivo explant model. MUC1 promoter was cloned and transcription regulation was studied by transient cell transfection to identify the bile acid-responsive regions. Signaling pathways involved were identified using specific pharmacologic inhibitors and siRNA approach.

RESULTS

Taurocholic, taurodeoxycholic, taurochenodeoxycholic, glycocholic, sodium glycocholate, and deoxycholic bile acids upregulated MUC1 mRNA and protein expression. The highest induction was obtained with deoxycholic and taurocholic acids in both cellular and explant models. The bile acid-mediated upregulation of MUC1 transcription occurs at the promoter level, with responsive elements located in the -1472/-234 region of the promoter, and involves the phosphatidylinositol 3-kinase signaling pathway.

CONCLUSIONS

Bile acids induce MUC1 mucin overexpression in human esophageal adenocarcinoma cells and tissues by activating its transcription through a process involving phosphatidylinositol 3-kinase.

Neither Antioxidants nor COX-2 Inhibition Protect Against Esophageal Inflammation in an Experimental Model of Severe Reflux

BACKGROUND

Reflux-induced injury and oxidative stress result in esophageal inflammation and the potential for progression to intestinal metaplasia and adenocarcinoma. Proton-pump inhibitors represent the standard medical approach, but anti-inflammatories and antioxidants offer novel therapeutic possibilities.

MATERIALS AND METHODS

Six weeks after an esophagojejunostomy reflux procedure, female Wistar rats (n = 100) were randomized to receive either an antioxidant (vitamin C, 8 mg or 28 mg/day), a cyclooxygenase-2 (COX-2) inhibitor (rofecoxib, 1 mg/day), or no therapy. After sacrifice 16 weeks later, esophageal injury was scored using pathologic and image analysis scoring.

RESULTS

Esophagitis was present in all 63 animals completing the study and severe in 27 (43%). No animal developed metaplasia or tumor. The extent of inflammation and esophageal ulceration were not significantly different between experimental groups.

CONCLUSIONS

In this model of reflux injury, antioxidants and COX-2 inhibitors failed to ameliorate the severe inflammation induced. Further experimental designs should evaluate these novel approaches in less severe experimental models.

Doppler optical coherence tomography monitoring of microvascular tissue response during photodynamic therapy in an animal model of Barrett's esophagus

BACKGROUND

Doppler optical coherence tomography (DOCT) is an imaging modality that allows assessment of the microvascular response during photodynamic therapy (PDT) and may be a powerful tool for treatment monitoring/optimization in conditions such as Barrett's esophagus (BE).

OBJECTIVE

To assess the technical feasibility of catheter-based intraluminal DOCT for monitoring the microvascular response during endoluminal PDT in an animal model of BE.

DESIGN

Thirteen female Sprague-Dawley rats underwent esophagojejunostomy to induce enteroesophageal reflux for 35 to 42 weeks and the formation of Barrett's mucosa. Of these, 9 received PDT by using the photosensitizer Photofrin (12.5 mg/kg intravenous), followed by 635-nm intraluminal light irradiation 24 hours after drug administration. The remaining 4 surgical rats underwent light irradiation without Photofrin (controls). Another group of 5 normal rats, without esophagojejunostomy, also received PDT. DOCT imaging of the esophagus by using a catheter-based probe (1.3-mm diameter) was performed before, during, and after light irradiation in all rats.

RESULTS

Distinct microstructural differences between normal squamous esophagus, BE, and the transition zone between the 2 tissues were observed on DOCT images. Similar submucosal microcirculatory effects (47%-73% vascular shutdown) were observed during PDT of normal esophagus and surgically induced BE. Controls displayed no significant microvascular changes.

CONCLUSIONS

No apparent difference was observed in the PDT-induced vascular response between normal rat esophagus and the BE rat model. Real-time monitoring of PDT-induced vascular changes by DOCT may be beneficial in optimizing PDT dosimetry in patients undergoing this therapy for BE and other conditions.

Bone morphogenetic protein 4 expressed in esophagitis induces a columnar phenotype in esophageal squamous cells

BACKGROUND & AIMS

Barrett's esophagus (BE) is a metaplastic condition in which normal squamous esophageal epithelium is replaced by columnar epithelium. It is proposed that one of the possible mechanisms is dedifferentiation of squamous epithelium into columnar epithelium. The pathophysiology through which this metaplasia occurs is unknown. A recent study by serial analysis of gene expression showed that bone morphogenetic protein 4 (BMP-4) is uniquely expressed in BE. In this study, the role of the BMP pathway in the metaplastic transformation of normal squamous cells into columnar cells was examined.

METHODS

Tissues from patients with esophagitis and BE and in an esophagitis-BE rat model were examined for the activation of the BMP pathway. Short-term cultures of primary normal squamous esophageal cells were treated with BMP-4, and cell biological changes were examined by Western blot analysis, immunohistochemistry, and microarrays.

RESULTS

In both human and rat tissues, the BMP pathway proved to be activated in esophagitis and BE. Upon incubation of squamous cell cultures with BMP-4, the cytokeratin expression pattern showed a shift that was consistent with columnar epithelium. Involvement of the BMP pathway was suggested by up-regulation of Phosphorylated-Smad 1/5/8 (P-Smad 1/5/8) that was effectively blocked by Noggin, a BMP antagonist. Comparison of the gene expression profiles of squamous cells, BMP-4-treated squamous cells, and BE cells showed a significant shift in the profile of the BMP-4-treated squamous cells toward that of the cultured BE cells.

CONCLUSIONS

These results suggest that the BMP pathway could play a role in the transformation of normal esophageal squamous cells into columnar cells.

Molecular biologic staging of esophageal cancer

The molecular biology of esophageal cancer is characterized by a series of genetic mutations that occur throughout the progression from normal squamous epithelium to carcinoma. The most important risk factor for the development of adenocarcinoma, which is increasing in incidence, is the presence of CLE. The pathophysiology of CLE appears to be related to duodenogastroesophageal reflux, also increasing in incidence. The genetic mutations that are responsible for tumorigenesis have been described, although the precise sequence of mutations is variable. Analysis of molecular biologic factors that are important in tumorigenesis may be used in clinical applications: establishing diagnosis, assessing prognosis, and assigning therapy. The development of molecular biologic substaging of patients with CLE may potentially identify patients with elevated malignant potential and expedite therapy. The ability of molecular markers to predict resistance to chemotherapy and radiation therapy represents an important potential advantage, with two possible applications. Predictable resistance to a particular chemotherapeutic agent would allow the selection of a alternative agent, with a greater potential for efficacy. Furthermore, known mechanisms of resistance, which have been analyzed using molecular markers, may be inhibited or reversed. The molecular biology of esophageal cancer requires further study. The molecular events and factors that are involved may be important in the diagnosis, staging, and treatment of esophageal cancer, in addition to the description of tumorigenesis.

Le reflux biliaire duodéno-gastrique et gastro-œsophagien

This study reviews current data regarding duodenogastric and gastroesophageal bile reflux-pathophysiology, clinical presentation, methods of diagnosis (namely, 24-hour intraluminal bile monitoring) and therapeutic management. Duodenogastric reflux (DGR) consists of retrograde passage of alkaline duodenal contents into the stomach; it may occur due to antroduodenal motility disorder (primary DGR) or may arise following surgical alteration of gastoduodenal anatomy or because of biliary pathology (secondary DGR). Pathologic DGR may generate symptoms of epigastric pain, nausea, and bilious vomiting. In patients with concomitant gastroesophageal reflux, the backwash of duodenal content into the lower esophagus can cause mixed (alkaline and acid) reflux esophagitis, and lead, in turn, to esophageal mucosal damage such as Barrett's metaplasia and adenocarcinoma. The treatment of DGR is difficult, non-specific, and relatively ineffective in controlling symptoms. Proton pump inhibitors decrease the upstream effects of DGR on the esophagus by decreasing the volume of secretions; promotility agents diminish gastric exposure to duodenal secretions by improving gastric emptying. In patients with severe reflux resistant to medical therapy, a duodenal diversion operation such as the duodenal switch procedure may be indicated.

Expression of the bile acid receptor FXR in Barrett's esophagus and enhancement of apoptosis by guggulsterone in vitro

BACKGROUND

Barrett's esophagus, a risk factor for esophageal adenocarcinoma, is associated with reflux disease. The aim of this study was to assess the expression of bile acid receptors in the esophagus (normal, esophagitis, Barrett's esophagus and adenocarcinoma) and to investigate their possible function.

RESULTS

the expression of the bile acid receptors FXR and VDR in esophageal biopsies from patients with a normal mucosa, esophagitis, Barrett's esophagus or adenocarcinoma (n = 6 per group) and in cell lines derived from Barrett's esophagus and esophageal adenocarcinoma, was assessed by real time Q-PCR and immunohistochemistry. The effect of guggulsterone, an antagonist of bile acid receptors, on apoptosis of Barrett's esophagus-derived cells was assessed morphologically, by flow cytometry and by measuring caspase 3 activity. The expression of FXR was increased in esophagitis, Barrett's esophagus and adenocarcinoma compared to normal mucosa by a mean of 44, 84 and 16, respectively. Immunohistochemistry showed a weak expression in normal esophagus, a strong focal reactivity in Barrett's esophagus, and was negative in adenocarcinoma. VDR expression did not significantly differ between groups. In cell cultures, the expression of FXR was high in Barrett's esophagus-derived cells and almost undetectable in adenocarcinoma-derived cells, whereas VDR expression in these cell lines was not significantly different. In vitro treatment with guggulsterone was associated with a significant increase in the percentage of apoptotic cells and of the caspase 3 activity.

CONCLUSION

the bile acid receptor FXR is significantly overexpressed in Barrett's esophagus compared to normal mucosa, esophagitis and esophageal adenocarcinoma. The induction of apoptosis by guggulsterone in a Barrett's esophagus-derived cell line suggests that FXR may contribute to the regulation of apoptosis.

Esophageal cancer after distal gastrectomy

The effect of gastrectomy on the subsequent development of esophageal cancer was investigated. Duodenogastroesophageal reflux is thought to be common in patients after distal gastrectomy, but whether this contributes to the development of esophageal cancer in such patients is controversial. We retrospectively evaluated 153 patients who underwent subtotal esophagectomy for thoracic esophageal cancer between January 2002 and July 2005. They were divided into two groups, according to whether or not they had previously undergone a gastrectomy: group 1, comprising 14 patients who had undergone gastrectomy and group 2, comprising 139 patients who had not. Clinical profiles of the patients were obtained from the medical records and the whole resected esophagus was histopathologically examined. The interval between gastrectomy and esophagectomy in group 1 was significantly shorter in the patients who had undergone gastrectomy for gastric cancer (10.5 +/- 4.2 years) than in those who had undergone gastrectomy for a peptic ulcer (28.9 +/- 3.0 years). The interval was also somehow shorter in the patients for whom anastomosis had been performed by Billroth I (21.3 +/- 5.6 years) compared with Billroth II (29.7 +/- 3.2 years), although the difference did not reach its statistical significance (P = 0.11). Moreover, the proportion of lower third tumors in patients after gastrectomy was significantly higher compared with that of the patients with intact stomach. These findings suggest that a history of gastrectomy is associated with more lower-third squamous cell esophageal carcinoma.

Histopathologic evaluation of an animal model for Barrett's esophagus and adenocarcinoma of the distal esophagus

INTRODUCTION

Barrett's esophagus and adenocarcinoma of the esophagus are related to long-standing duodeno-gastroesophageal reflux. The development of an animal model in which Barrett's esophagus and/or carcinoma is induced by duodeno-(gastro-)esophageal reflux could provide better understanding of the pathogenesis of the metaplasia-dysplasia-carcinoma sequence and would create the possibility of investigating new treatment strategies for this aggressive disease.

MATERIALS AND METHODS

Two rat models were analyzed. In the first experiment, 44 male Sprague Dawley rats underwent end-to-side esophagojejunostomy with gastric resection, to ensure duodenoesophageal reflux without gastric acid. In the second experiment a side-to-side esophago-gastrojejunostomy was performed in 30 rats, ensuring duodeno-gastroesophageal reflux. In both experiments animals were not exposed to any exogenous carcinogens during the experiment. Sequential morphological changes (i.e., esophagitis, intestinal metaplasia, dysplasia, and carcinoma) were studied after 4, 6, and 12 months. To analyze histopathologic characteristics, evaluation of the hematoxylin and eosin specimens was combined with immunohistochemical stainings for high-iron diamine-alcian blue, alcian blue/periodic acid-Schiff, the proliferation marker PCNA, and mutations in the tumor suppressor gene p53.

RESULTS

In the first experiment, only 11 animals survived the postoperative period. These animals had to be sacrificed at a median of 11 weeks due to persistent weight loss and failure to thrive. Severe ulcerative esophagitis was seen in all animals, with a 2-mm segment of metaplastic epithelium found at the anastomosis. In four animals a large, well-differentiated, mucinous tumor without malignant characteristics was observed. In the second experiment, eight animals died postoperatively. Twelve animals were sacrificed according to protocol at 4 or 6 months. In these animals, extensive esophagitis with squamous cell hyperplasia was found. In addition, a short (2 mm) segment of metaplastic epithelium was observed, without dysplasia. The remaining animals survived 1 year. After 1 year, 9 of the 10 animals had developed a glandular metaplastic segment (median length, 10 mm), which was histologically and immunohistologically characteristic for the specialized columnar epithelium of Barrett's esophagus without signs of dysplasia. Finally, in seven animals a mucinous tumor with cytologic characteristics of a well-differentiated mucinous adenocarcinoma was found without infiltrative growth. These tumors were always found at the site of the anastomosis, originated in the submucosa, and did not reach either the luminal surface or the muscular layer. The mucinous lesions were not positive for p53, and PCNA was only slightly increased. Although they showed cytological characteristics of malignancy, histopathologic evaluation was more suggestive of a reactive mucous producing lesion fitting the diagnosis "esophagitis cystica profunda."

CONCLUSION

This study demonstrates the development of a long Barrett's segment in an animal duodeno-gastroesophageal reflux model. Although mucinous tumors resembling adenocarcinomas develop around the anastomosis, these are probably not reflux induced and are more likely to be reactive lesions. However, the true nature of these tumors remains to be elucidated.

A "crackleware" oesophagus

This case report describes a 70 year old woman with excessive diffuse keratinisation of the oral cavity and oesophagus harbouring a squamous cell carcinoma. This excessive diffuse keratinisation of normally non-keratinised squamous epithelium could not be identified in normally non-keratinised epithelia in other parts of the body (the vagina), arguing against a genetic basis for this disorder. The term "crackleware" oesophagus was used to describe this entity, which has not been described previously in the English literature.

Nonesophageal side-effects after antireflux surgery plus acid-suppression duodenal diversion surgery in patients with long-segment Barrett's esophagus*

During the last years we have employed acid-suppression duodenal diversion procedures (truncal vagotomy-partial gastrectomy plus Roux-en-Y gastrojejunostomy) in addition to antireflux surgery in order to treat all the pathophysiological factors involved in the genesis of Barrett's esophagus. We have observed very good results concerning the clinical and objective control of GERD at the long-term follow up after this procedure. However, it could be associated with other nonesophageal symptoms or side-effects. This study was conducted to evaluate the presence of gastrointestinal symptoms (diarrhea, vomiting, dumping, weight loss and anastomotic ulcers) after this operation. In this prospective study 73 patients were assessed using a careful clinical questionnaire asking regarding these complications at the early (< 6 months) and late (> 6 months) follow-up (average of 32.4 months). In the early postoperative period, diarrhea was present in 64% (19% considered severe 10-90 days after surgery), dumping in 41% and loss of weight in 71% of cases. Diarrhea occurred daily in 47.7% in the early postoperative period, but only in 16% of cases after 1 year. Shortly after surgery, steatorrea was observed in 9% of cases and responded well to medical treatment. Severe diarrhea or dumping was rare (5% of cases). These symptoms improved significantly after 1 year with medical management (45%, 20% and 30%, respectively) and 42% of patients regained their normal body weight. Only two patients presented anastomotic ulcers and were treated satisfactory with proton pump inhibitors. Revisional surgery was indicated in two patients with severe dumping syndrome. Most side-effects identified by this study were mild and diminished 1 year after operation.

Biologic properties of columnar epithelium underneath reepithelialized squamous mucosa in Barrett's esophagus

Chronic proton pump inhibitor (PPI) therapy may lead to partial regression of Barrett's esophagus (BE), resulting in the development of reepithelialized islands of squamous mucosa that may cover the underlying BE. The purpose of this study was to evaluate the clinical, histologic, and biologic characteristics of BE that is situated underneath squamous islands (BUSI). A total of 97 mucosal biopsies from 44 BE patients with BUSI were evaluated for a variety of histologic features (eg, type of epithelium, anatomic relationship of the underlying glands to the luminal surface, presence of adjacent mucosal glands or ducts, and the presence and degree of dysplasia), and immunostained for Ki-67, cyclin D1, and p53. BUSI was compared with adjacent areas of BE for all parameters. A clinical control group consisting of 50 BE patients without microscopic evidence of BUSI was selected for comparison of clinical and endoscopic features. The study group (34 males, 10 females; mean age, 67 years; mean length of BE, 5.5 cm) consisted of 27 (61%) and 12 (27%) patients on low- and high-dose PPI, respectively. On endoscopy, visible islands of squamous mucosa were noted in only 43% of study group patients (despite the presence of BUSI microscopically in all cases); one island was noted in 2%, multiple islands in 27%, and extensive islands in 14% of patients. The extent of squamous islands was unrelated to PPI dose. The study group was significantly more likely to have endoscopic evidence of extensive squamous islands compared with the control group (P = 0.009). Histologically, 89% of biopsies with BUSI showed intestinal-type, and 11% showed cardia-type, epithelium. Low- and high-grade dysplasia was noted in 4 (4%) and 5 (5%) biopsies, respectively. All patients with dysplasia in BUSI also showed dysplasia in other areas of the esophagus as well. Interestingly, BUSI reached the mucosal surface either by penetrating directly through, or by wrapping around, islands of squamous epithelium, in 68% of biopsies. Twenty-one percent of biopsies showed BUSI adjacent to submucosal glands or ducts. BUSI showed a significantly lower Ki-67 proliferation rate (29% vs. 49%, P < 0.001), and a lower, albeit nonsignificant, degree of cyclin D1 (16% vs. 29%) and p53 (4% vs. 17%) positivity in comparison to adjacent areas of BE. Furthermore, significantly lower proliferation rates were observed in BUSI that did not reveal an opening to the mucosal surface in comparison to foci that did. BUSI is phenotypically similar to typical surface BE but shows less severe proliferative abnormalities, particularly in buried glands that have no detectable connection to the esophageal lumen. Reduced proliferation may be due either to decreased exposure to luminal contents or to disruption of sloughing of surface epithelial cells into the crypt lumen. Prospective studies of large numbers of patients with BUSI will be required to determine the magnitude of its risk of progression to cancer.

Impact of the biliary diversion procedure on carcinogenesis in Barrett's esophagus surgically induced by duodenoesophageal reflux in rats

OBJECTIVE

To determine whether the elimination of bile reflux in the established esophagojejunostomy model of Barrett's esophagus (BE) will reduce or eliminate the risk of developing esophageal adenocarcinoma.

SUMMARY BACKGROUND DATA

Reflux of duodenal juice as well as gastric acid plays an important role in the pathogenesis of BE and adenocarcinoma. Duodenoesophageal reflux (DER) per se induces these diseases without carcinogen. However, it is unclear whether antireflux surgery induces regression of BE and prevents adenocarcinoma.

METHODS

Two hundred F344 male rats underwent one of following 3 operations: (1) total gastrectomy and esophagojejunostomy to induce DER, followed by killing after 20 (n = 13), 30 (n = 12), and 50 weeks (n = 30); (2) biliary diversion procedure, converted to Roux-en-Y method, to avoid bile regurgitation into the esophagus at 20 (n = 29) and 30 weeks (n = 32) after the operation to induce DER, followed by killing 50 weeks after initial operation; or (3) total gastrectomy and Roux-en-Y esophagojejunostomy followed by killing after 50 weeks served as controls (n = 28).

RESULTS

BE developed in more than half of the animals exposed to DER for 20 weeks, in more than 90% of rats with DER for 30 weeks, and in 100% of animals exposed to DER for 50 weeks. In the incidence and the length of BE, there is no difference between the animals that underwent biliary diversion at 20 (62%) and 30 weeks (94%) and those that had DER for 20 (54%) and 30 weeks (92%), respectively. Incidence of adenocarcinoma was significantly lower in the rats that underwent the biliary diversion procedure after 30 (19%) and 20 weeks (3%) than in the rats that had DER for 50 weeks (60%) (P < 0.005). None of the control animals that underwent Roux-en-Y esophagojejunostomy developed BE and carcinoma.

CONCLUSIONS

It is likely that the converting procedure from the esophagojejunostomy to induce DER to biliary diversion does not lead to regression of BE but prevents the development of esophageal adenocarcinoma in the rats.

p27 and Barrett's esophagus: a review*

The rising prevalence of Barrett's esophagus and Barrett's associated adenocarcinoma in the Western world has stimulated increasing interest in this disease. This has resulted in a plethora of articles concerning its molecular biology, but the tumor suppressor gene, p27, has received little attention. In this article, we review the literature concerning the role of p27 in Barrett's esophagus and its malignant transformation, and we evaluate its possible role as an important clinical biomarker, as well as potential chemopreventive clinical agents aimed at substituting its antitumoral activity.

Barrett's esophagus: best of Digestive Disease Week 2003

The definition of Barrett's esophagus is conceptually simple. It is the replacement of the normal squamous mucosa by specialized intestinal metaplasia within the esophagus. Barrett's esophagus would only be a clinical curiosity if not for its predisposition toward neoplastic change. In spite of all the knowledge and data gathered thus far on Barrett's, much remains unknown. Why do some patients develop Barrett's while others do not? Why do some with Barrett's advance to adenocarcinoma? Once Barrett's develops, what is the optimal prevention strategy for adenocarcinoma? These clinical unknowns touch only the tip of the iceberg and have made Barrett's esophagus a subject of intense research. This review offers some of the highlights from Digestive Disease Week 2003, comprised of posters of distinction and oral presentations.

High grade dysplasia: surveillance, mucosal ablation, or resection?

Barrett's esophagus is a common premalignant condition that results from chronic gastroesophageal reflux. High grade dysplasia in the metaplastic esophagus is thought to be the last step in the metaplasia-to-carcinoma sequence that characterizes this disease. The management of high grade dysplasia in Barrett's esophagus is controversial. Some investigators advocate a rigorous endoscopic surveillance program with biopsies, but this approach has been questioned because of its clinical impracticality, high cost, possibility of sampling errors, and difficulty demonstrating effectiveness on a reproducible basis. Others advocate mucosal ablative therapy to eradicate the dysplastic and metaplastic epithelium. This approach, still in its infancy, cannot be accepted as standard therapy at the present time because of limited follow-up, its questionable ability to completely eradicate the abnormal mucosa, the phenomenon of pseudoregression, and the patients require continued rigorous endoscopic surveillance. Esophagectomy, on the other hand, can be accomplished with a low mortality rate in these patients. We advocate this approach because a large number of them have invasive cancer in the esophagus despite a preoperative diagnosis of only high grade dysplasia. In addition, the 5-year survival is excellent even if invasive cancer is present, and these patients are liberated from rigorous endoscopic surveillance for the rest of their lives. For patients with high grade dysplasia in Barrett's esophagus who are poor operative risks, less invasive approaches such as mucosal ablation may play a role, but longer follow-up information is needed before this technique can be accepted even in this setting.

Barrett's oesophagus: optimal strategies for prevention and treatment

Barrett's oesophagus is a change in the lining of the distal oesophagus recognised at endoscopy and documented to have intestinal metaplasia by biopsy. It is thought that it is an acquired condition resulting from chronic gastro-oesophageal reflux disease (GORD). Barrett's oesophagus has the potential to progress to adenocarcinoma of the oesophagus. Evidence to support the association between Barrett's oesophagus and GORD appears to be strong but circumstantial. The intermediate steps that lead from GORD to Barrett's oesophagus are speculative and the timeline for the development of this condition remains obscure. It has yet to be demonstrated that erosive oesophagitis is a necessary intermediate step for the development of Barrett's oesophagus. In spite of effective therapy, documentation that medical or surgical therapy prevents Barrett's oesophagus is lacking. The goal of screening for Barrett's oesophagus is ultimately to improve the survival of patients with adenocarcinoma of the oesophagus. This goal has not been achieved and the evidence-based criteria for screening remain to be defined. Medical and surgical therapy of Barrett's oesophagus is effective in controlling reflux, although not proven to prevent neoplastic progression of the at risk mucosa. Endoscopic techniques of mucosal injury have been applied as alternatives to oesophagectomy in efforts to prevent progression to cancer. Surveillance endoscopy and biopsy is the currently accepted method aimed at early intervention and improved survival for oesophageal adenocarcinoma. A working surveillance protocol to accomplish this is proposed based on dysplasia grade. If no dysplasia is found and confirmed with subsequent endoscopy and biopsy, a 3-year interval is recommended. If only low grade dysplasia is confirmed, then annual endoscopy until no dysplasia is recognised is recommended. On the basis of defined risk factors, high grade dysplasia can lead to intense surveillance every 3 months or an intervention. Future developments in understanding the biology of Barrett's oesophagus and in therapeutic interventions will provide an opportunity for more effective screening, surveillance and prevention of neoplastic progression.

Changing role of in vivo models in columnar-lined lower esophagus

Columnar-lined lower esophagus (CLE) or Barrett's esophagus (BE) is caused by chronic reflux of the gastrointestinal tract and can progress to invasive adenocarcinoma. However, the pathophysiology, cell of origin, and management of this condition is incompletely understood. This review evaluates the role of in vivo models in resolving these debates. A search was performed on the Ovid and Pub Medline for 1964-2001 and Cochrane Collaboration. The keywords used were adenocarcinoma, animal model, Barrett's esophagus, columnar-lined esophagus, esophageal neoplasms, and esophageal carcinogenesis. All relevant papers were scrutinized and an attempt at tabulation was made. In vivo models have been used at several stages of debate on the pathophysiology of BE. They provide conclusive evidence for its acquired nature secondary to duodenogastroesophageal reflux. The cell of origin of experimental BE may arise from adjacent columnar epithelium, basal layer multipotent cells, or esophageal glands. Experimental work on BE is lacking in assessing therapeutic modalities.

Gastric emptying time, not enterogastric reflux, is related to symptoms after upper gastrointestinal/biliary surgery

BACKGROUND

It has been suggested that symptoms from bile reflux gastritis are related to the frequency and degree of enterogastric reflux (EGR).

METHODS

Patients with history of upper gastrointestinal surgery or cholecystectomy as well as control patients were studied. Presence of EGR, degree of EGR, and gastric bile emptying time were assessed and quantified via 99mTC scintillation imaging and then compared between symptomatic and asymptomatic patients.

RESULTS

Patients with vagotomy and pyloroplasty, Billroth I, Billroth II, and cholecystectomy demonstrated statistically higher degrees of EGR compared with controls. Although asymptomatic and symptomatic patients with a history of upper gastrointestinal or biliary surgery demonstrated no statistically significant differences between incidence of EGR and degree of EGR, there was a statistically significant difference in gastric emptying time.

CONCLUSIONS

Delayed gastric emptying time, not frequency or extent of EGR, was associated with the symptoms of bile reflux in patients who had previous upper gastrointestinal or biliary operations.

Reconstructive procedure after distal gastrectomy for gastric cancer that best prevents duodenogastroesophageal reflux

Billroth I and II reconstructions are commonly performed after distal gastrectomy. Both may cause duodenogastric and duodenogastroesophageal reflux, conditions reported to have carcinogenetic potential. The aim of this study was to investigate which reconstructive procedure would most effectively prevent bile reflux into the gastric remnant and esophagus after distal gastrectomy. A group of 92 patients who underwent curative distal gastrectomy for gastric cancer were subjected and classified into three groups retrospectively by the reconstructive procedure undertaken: group A, Roux-en-Y (Roux-Y) reconstruction (n = 29); group B, Billroth I reconstruction (n = 41); group C, Billroth II reconstruction (n = 22). The bile reflux periods (percent time) for the gastric remnant and esophagus were measured with the Bilitec 2000 under standardized conditions. The percent time for the gastric remnant was significantly less in group A than in group B or C. In 61% of all patients, bile reflux into the esophagus was found to be more than 5.0% of the time; it was less in group A than in group B or C (p = 0.057). A questionnaire revealed a good correlation between the incidence of reflux symptoms and the percent time for the gastric remnant and esophagus. Roux-Y reconstruction is superior to either Billroth I or II reconstruction for preventing bile reflux into the gastric remnant and esophagus after distal gastrectomy.

Gastric emptying and duodeno-gastro-oesophageal reflux in gastro-oesophageal reflux disease

BACKGROUND

Previous studies present conflicting results regarding relationship between gastric emptying and gastro-oesophageal reflux disease. Reflux of duodenal content to oesophagus is generally considered to be associated with more severe disease.

AIM

To assess presence of a gastric emptying disorder in persons with reflux of duodenal contents to oesophagus and to identify any correlation with gastric emptying and oesophageal motility.

METHODOLOGY

A total of 15 subjects with (B+) and 15 subjects without (B-) bile reflux to oesophagus determined by 24-hour bilirubin monitoring were studied with scintigraphic solid gastric emptying and 24-hour oesophageal manometry.

RESULTS

There was no difference in lag phase [median 23.7 (range 10.8-44.0) vs 24.6 (8.1-40.1) min], half emptying time [74.6 (48.0-93.6) vs 82.8 (54.4-153.9) min] or emptying rate [0.89 (0.59-1.34) vs 0.83 (0.36-1. 15)%/min] for B- and B+ subjects, respectively. In addition, there was no difference in emptying rate of gastric fundus between B- and B+ subjects. Subjects with bile reflux had less effective oesophageal contractions of oesophageal body [9.4(3.3-37)%] compared to subjects without bile reflux [32(19-47)%, p = 0.002]. However, there was no correlation between oesophageal motility and gastric emptying.

CONCLUSION

Results suggest that a gastric emptying disorder is a less likely contributing cause of bile reflux to the oesophagus, but bile reflux is associated with less effective oesophageal motility.

Chemoprevention of esophageal adenocarcinoma by COX-2 inhibitors in an animal model of Barrett's esophagus

BACKGROUND & AIMS

Carcinogenesis in Barrett's esophagus (BE) is associated with an increased expression of cyclooxygenase (COX) 2. However, there has been no direct evidence that inhibition of COX-2 prevents cancer in BE. We studied the effect of MF-Tricyclic, a selective COX-2 inhibitor, on the development of BE and adenocarcinoma in a rat model.

METHODS

Four weeks after esophagojejunostomy, 105 Sprague-Dawley rats were randomized to a chow containing MF-Tricyclic or Sulindac, or a placebo. Ninety-six (92%) rats completed the study and were sacrificed at 28 +/- 2 weeks. The animals were assessed for the presence of cancer, tumor volume, BE, degree of inflammation, and COX-2 expression and activity.

RESULTS

MF-Tricyclic and Sulindac reduced the relative risk of development of esophageal cancer by 55% (95% confidence interval [CI] = 43%-66%, P < 0.008) and by 79% (95% CI = 68%-87%, P < 0.001), respectively, compared with controls. No significant differences were noted in the risk of esophageal cancer between the MF-Tricyclic and the Sulindac group (P = 0.34). The median tumor volume was not significantly different among the 3 groups (P = 0.081). Moderate to severe degree of inflammation was significantly more common (P = 0.005) in the control compared with the MF-Tricyclic and the Sulindac group; however, the prevalence of BE was not significantly different between groups (P = 0.98). Rats in the control group had higher tissue PGE2 level compared with the MF-Tricyclic and Sulindac groups (P = 0.038).

CONCLUSIONS

Selective and nonselective COX-2 inhibitors can inhibit inflammation, COX-2 activity, and development of adenocarcinoma induced by reflux. This provides direct evidence that COX-2 inhibitors may have chemopreventive potential in BE.

Results of the Collis-Nissen gastroplasty to control reflux disease in patients who have Barrett's esophagus

Barrett's esophagus is an end-stage gastroesophageal reflux complication with a potential for malignant transformation. This condition probably is involved in esophageal cancer being perceived today as the most rapidly increasing cancer in Western countries. Numerous observations suggest that standard antireflux operations fail over time because of long-term inflammatory and fibrotic changes in the esophageal wall that cause shortening of the esophagus. The addition of esophageal elongation by gastroplasty provides a reliable repair by creation of a tension-free repair, whereas the durable antireflux effects are provided by the total fundoplication around the neoesophagus. The restored LES tone further helps control the mucosal damage and the chronic inflammatory changes. Complete regression of the abnormal mucosa still does not occur, and persistent irritation of that mucosa still entails the risk for progression toward dysplasia. The natural history of the columnar-lined mucosa in BE may be altered by medical or surgical intervention. It is too early to judge in which settings these interventions will be meaningful.

Increased DNA adducts in Barrett's esophagus and reflux-related esophageal malignancies

BACKGROUND

DNA adduct formation can initiate carcinogenic processes.

AIM

To examine the pre-malignant condition of Barrett's esophagus by measuring the DNA adducts.

METHODS

DNA adducts were measured in the proximal and distal esophagus of patients with Barrett's esophagus (n = 9), patients with adenocarcinoma in the distal esophagus/esophagogastric junction (n = 28), and in control group of patients (n = 8) using the 32-P-postlabeling method. The average levels of DNA adducts are expressed as mean adducts/10(9) nucleotides + standard error of the mean. RESULTS. The average DNA adduct levels in the distal esophagus were significantly higher in both the Barrett's esophagus (24.5 +/- 7.9) and the adenocarcinoma (12.0 + 3.0) than in the control patients (0.1 +/- 0.08), P < 0.001. In the proximal esophagus, the DNA adduct levels were approximately equal in the Barrett's esophagus (7.0 +/- 1.0) and in the adenocarcinoma group (6.4 +/- 0.65). However, the levels in the proximal esophagus in both groups were significantly higher than in the control group (2.1 +/- 0.67), P < 0.05.

CONCLUSIONS

Patients with Barrett's esophagus and patients with esophageal/esophagogastric junction adenocarcinoma had significantly more DNA adducts than the control group. These results support the current concept of the carcinogenic potential of chronic gastroesophageal reflux, and the pre-malignant condition of Barrett's esophagus.

Adenocarcinoma of the rat esophagus in the presence of a proton pump inhibitor: a pilot study

This study examines the effects of a proton pump inhibitor on a rat model of duodenogastric reflux. Duodenoesophageal reflux was induced in 60 rats by performing a duodenesophagostomy. The study group received daily intraperitoneal injections of a proton pump inhibitor for 6 months and the control group received an equivalent injection of saline. Rats were examined at death for macroscopic tumor, dysplasia, adenocystic changes, papillomatosis, and adenocarcinoma. Five out of 19 rats in the study group and three out of 20 rats in the control group developed dysplastic/adenocarcinomatous changes. Ten of the rats in the study group died before the end of the study, as opposed to one in the control group (this is not statistically significant). There was no difference in the number of cancers that developed in the two groups. However, there was an insignificant trend to earlier appearance of detectable disease in the study group.

Association between cholecystectomy and adenocarcinoma of the esophagus

BACKGROUND & AIMS

Barrett's esophagus, which is linked to adenocarcinoma of the esophagus, is associated with reflux of bile. Duodenogastric reflux is increased after cholecystectomy. This study aims to evaluate if cholecystectomy is associated with an increased risk of adenocarcinoma of the esophagus.

METHODS

A population-based cohort study of cholecystectomized patients in Sweden between 1965 and 1997 cross-linked with the Swedish Cancer Register.

RESULTS

Cholecystectomized patients had an increased risk of adenocarcinoma of the esophagus (standardized incidence ratio [SIR], 1.3; 95% confidence interval [CI], 1.0-1.8). Esophageal squamous-cell carcinoma was not found to be associated with cholecystectomy (SIR, 0.9; 95% CI, 0.7-1.1). Patients with gallstone disease on whom surgery was not performed did not have an increased risk of adenocarcinoma or squamous-cell carcinoma of the esophagus.

CONCLUSIONS

Cholecystectomy is associated with a moderately increased risk of adenocarcinoma of the esophagus, possibly by the toxic effect of refluxed duodenal juice on the esophageal mucosa. Further studies are needed regarding the link between bile reflux and esophageal carcinogenesis.

Expression of cyclin D1 and p53 and its correlation with proliferative activity in the spectrum of esophageal carcinomas induced after duodenal content reflux and 2,6-dimethylnitrosomorpholine administration in rats

Alterations in expression of the p53 and cyclin D1 genes have been implicated in the development of esophageal carcinomas in both humans and animal models. We hypothesize that altered expression of cyclin D1 and p53 may be involved in the sequential development of esophageal carcinomas with glandular differentiation induced by the carcinogen, 2,6-dimethylnitrosomorpholine (DMNM) in rats with duodenal content reflux esophagitis. In the present study Sprague-Dawley rats were given DMNM 15 days after performing an esophago-jejunostomy in order to induce chronic duodenal content reflux esophagitis. Expression and localization of p53, cyclin D1 and Ki-67 were examined by immunohistochemical analyses. Twenty of 24 animals developed different types of esophageal carcinomas, including pure squamous carcinoma, adenosquamous carcinoma and pure adenocarcinoma. Undifferentiated basaloid areas were frequently observed in these tumors. Cyclin D1 overexpression was observed in hyperplastic lesions and increased through dysplasia and in undifferentiated areas of infiltrating carcinoma. Cyclin D1 expression coincided with increased Ki-67 expression and decreased along with cell differentiation. The p53 immunohistochemical pattern was parallel to that of cyclin D1, although the percentage of positive cells was usually smaller in all lesions and increased p53 expression started at the dysplastic stage. These findings suggest that overexpression of cyclin D1 may be an early event in DMNM-induced rat esophageal tumorigenesis, causing increased proliferation of esophageal stem cells. Abnormal p53 expression may then be required to promote the development of neoplastic transformation from dysplastic epithelium through invasive phenotype, being more evident in cancer cells with squamous differentiation.