Does screening for Barrett's esophagus and adenocarcinoma of the esophagus prolong survival?

Professionals' views on the justification for esophageal adenocarcinoma screening: A systematic literature search and qualitative analysis

Screening for early esophageal adenocarcinoma (EAC), including screening for its precursor Barrett's esophagus (BE), has the potential to reduce EAC-related mortality and morbidity. This literature review aimed to explore professionals' views on the justification for EAC screening. A systematic search of Ovid Medline, EMBASE, and PsycInfo, from January 1, 2000 to September 22, 2022, identified 5 original studies and 63 expert opinion articles reporting professionals' perspectives on EAC screening. Included articles were qualitatively analyzed using the framework method, which was deductively led by modernized screening principles. The analyses showed that many professionals are optimistic about technological advancements in BE detection and treatment. However, views on whether the societal burden of EAC merits screening were contradictory. In addition, knowledge of the long-term benefits and risks of EAC screening is still considered insufficient. There is no consensus on who to screen, how often to screen, which screening test to use, and how to manage non-dysplastic BE. Professionals further point out the need to develop technology that facilitates automated test sample processing and public education strategies that avoid causing disproportionately high cancer worry and social stigma. In conclusion, modernized screening principles are currently insufficiently fulfilled to justify widespread screening for EAC. Results from future clinical screening trials and risk prediction modeling studies may shift professionals' thoughts regarding justification for EAC screening.

Screening for Barrett's Esophagus

The large increase in the incidence of esophageal adenocarcinoma in the West during the past 30 years has stimulated interest in screening for Barrett's esophagus (BE), a precursor to esophageal cancer. Effective endoscopic treatments for dysplasia and intramucosal cancer, coupled with screening programs to detect BE, could help reverse the increase in the incidence of esophageal cancer. However, there are no accurate, cost-effective, minimally invasive techniques available to screen for BE, reducing the enthusiasm of gastroenterologists. Over the past 5 years, there has been significant progress in the development of screening technologies. We review existing and developing technologies, new minimally invasive imaging techniques, nonendoscopic devices for cell collection, and biomarkers that can be measured in blood or stool samples. We discuss the status of these approaches, data from clinical studies of their effects, and their anticipated strengths and weaknesses in screening. The area is rapidly evolving, and new tools will soon be ready for prime time.

Screening for Barrett's esophagus: results from a population-based survey

BACKGROUND

Screening for Barrett's esophagus (BE) and adenocarcinoma (EAC) is controversial, but interest remains in finding the optimal method. Attitudes on screening within the community are unknown. We aimed to assess these attitudes via a survey.

STUDY

A mixed-mode survey was conducted in adults >50 years to assess awareness regarding BE, willingness to participate in screening, and preferences regarding method of screening. Methods evaluated were sedated endoscopy (sEGD), unsedated transnasal endoscopy (uTNE) and video capsule (VCE).

RESULTS

A total of 136 from 413 (33%) adults responded [47% males, mean (SD) age 63 (10.2) years], and 26% of responders knew of BE at baseline. After reading the information on BE, 72% were interested in screening. A history of undergoing screening tests and GI symptoms were predictive of interest. Unsedated techniques were preferred by 64% (VCE: 56% and uTNE: 8%) versus sEGD (36%).

CONCLUSIONS

The majority of adults were willing to undergo screening for BE/EAC, with a preference for unsedated techniques.

Accuracy and interrater reliability for the diagnosis of Barrett's neoplasia among users of a novel, portable high-resolution microendoscope

The high-resolution microendoscope (HRME) is a novel imaging modality that may be useful in the surveillance of Barrett's esophagus in low-resource or community-based settings. In order to assess accuracy and interrater reliability of microendoscopists in identifying Barrett's-associated neoplasia using HRME images, we recruited 20 gastroenterologists with no microendoscopic experience and three expert microendoscopists in a large academic hospital in New York City to interpret HRME images. They prospectively reviewed 40 HRME images from 28 consecutive patients undergoing surveillance for metaplasia and low-grade dysplasia and/or evaluation for high-grade dysplasia or cancer. Images were reviewed in a blinded fashion, after a 4-minute training with 11 representative images. All imaged sites were biopsied and interpreted by an expert pathologist. Sensitivity of all endoscopists for identification of high-grade dysplasia or cancer was 0.90 (95% confidence interval [CI]: 0.88-0.92) and specificity was 0.82 (95% CI: 0.79-0.85). Positive and negative predictive values were 0.72 (95% CI: 0.68-0.77) and 0.94 (95% CI: 0.92-0.96), respectively. No significant differences in accuracy were observed between experts and novices (0.90 vs. 0.84). The kappa statistic for all raters was 0.56 (95% CI: 0.54-0.58), and the difference between groups was not significant (0.64 vs. 0.55). These data suggest that gastroenterologists can diagnose Barrett's-related neoplasia on HRME images with high sensitivity and specificity, without the aid of prior microendoscopy experience.

Diagnosis and management of Barrett's esophagus

Barrett esophagus is characterized by the replacement of squamous mucosa in the esophagus by specialized intestinal metaplasia. Its clinical significance lies in it being the strongest risk factor for and known precursor for esophageal adenocarcinoma. Diagnosis requires endoscopic confirmation of columnar metaplasia in the distal esophagus and histologic confirmation of specialized intestinal metaplasia. Recommendations for the management of subjects diagnosed with Barrett esophagus include periodic endoscopic surveillance to detect the development of high-grade dysplasia or adenocarcinoma. Careful endoscopic evaluation with high-resolution endoscopy and endoscopic resection is recommended in the evaluation of subjects with high-grade dysplasia and early adenocarcinoma.

Diagnosis and management of Barrett's esophagus

Barrett esophagus is characterized by the replacement of squamous mucosa in the esophagus by specialized intestinal metaplasia. Its clinical significance lies in it being the strongest risk factor for and known precursor for esophageal adenocarcinoma. Diagnosis requires endoscopic confirmation of columnar metaplasia in the distal esophagus and histologic confirmation of specialized intestinal metaplasia. Recommendations for the management of subjects diagnosed with Barrett esophagus include periodic endoscopic surveillance to detect the development of high-grade dysplasia or adenocarcinoma. Careful endoscopic evaluation with high-resolution endoscopy and endoscopic resection is recommended in the evaluation of subjects with high-grade dysplasia and early adenocarcinoma.

Endoscopic imaging: How far are we from real-time histology?

Currently, in gastrointestinal endoscopy there is increasing interest in high resolution endoscopic technologies that can complement high-definition white light endoscopy by providing real-time subcellular imaging of the epithelial surface. These ‘optical biopsy’ technologies offer the potential to improve diagnostic accuracy and yield, while facilitating real-time decision-making. Although many endoscopic techniques have preliminarily shown high accuracy rates, these technologies are still evolving. This review will provide an overview of the most promising high-resolution imaging technologies, including high resolution microendoscopy, optical coherence tomography, endocytoscopy and confocal laser endoscopy. This review will also discuss the application and current limitations of these technologies for the early detection of neoplasia in Barrett’s esophagus, ulcerative colitis and colorectal cancer.

Epidermal growth factor receptor (EGFR) is overexpressed in high-grade dysplasia and adenocarcinoma of the esophagus and may represent a biomarker of histological progression in Barrett's esophagus (BE)

OBJECTIVES

The assessment of cancer risk in patients with Barrett's esophagus (BE) is currently fraught with difficulty. The current gold standard method of assessing cancer risk is histological assessment, with the appearance of high-grade dysplasia (HGD) as the key event monitored. Sampling error during endoscopy limits the usefulness of this approach, and there has been much recent interest in supplementing histological assessment with molecular markers, which may aid in patient stratification.

METHODS

No molecular marker has been yet validated to accurately correlate with esophageal histological progression. Here, we assessed the suitability of several membranous proteins as biomarkers by correlating their abundance with histological progression. In all, 107 patient samples, from 100 patients, were arranged on a tissue microarray (TMA) and represented the various stages of histological progression in BE. This TMA was probed with antibodies for eight receptor proteins (mostly membranous).

RESULTS

Epidermal growth factor receptor (EGFR) staining was found to be the most promising biomarker identified with clear increases in staining accompanying histological progression. Further, immunohistochemistry was performed using the full-tissue sections from BE, HGD, and adenocarcinoma tissues, which confirmed the stepwise increase in EGFR abundance. Using a robust H-score analysis, EGFR abundance was shown to increase 13-fold in the adenocarcinoma tissues compared to the BE tissues. EGFR was "overexpressed" in 35% of HGD specimens and 80% of adenocarcinoma specimens when using the H-score of the BE patients (plus 3 s.d.) as the threshold to define overexpression. EGFR staining was also noted to be higher in BE tissues adjacent to HGD/adenocarcinoma. Western blotting, although showing more EGFR protein in the adenocarcinomas compared to the BE tissue, was highly variable. EGFR overexpression was accompanied by aneuploidy (gain) of chromosome 7, plus amplification of the EGFR locus. Finally, the bile acid deoxycholic acid (DCA) (at neutral and acidic pH) and acid alone was capable of upregulating EGFR mRNA in vitro, and in the case of neutral pH DCA, this was NF-κB dependent.

CONCLUSIONS

EGFR is overexpressed during the histological progression in BE tissues and hence may be useful as a biomarker of histological progression. Furthermore, as EGFR is a membranous protein expressed on the luminal surface of the esophageal mucosa, it may also be a useful target for biopsy guidance during endoscopy.

Surveillance in Barrett's esophagus: an audit of practice

GOALS

Determine the rates of follow-up, incident rate of cancer during surveillance, and changes in pathologic grade of patients with Barrett's esophagus during surveillance in a gastroenterology practice without a formal surveillance program.

BACKGROUND

Barrett's esophagus is a pre-malignant condition. Surveillance endoscopy (SE) is recommended in order to detect and treat high-grade dysplasia and esophageal adenocarcinoma early and prevent deaths. SE has not been shown to have mortality benefit and several studies have questioned its cost-effectiveness. Most gastroenterology practices do not have a surveillance program for Barrett's esophagus. The few that exist are only in very specialized and funded programs. Little information exists on outcomes in patients with Barrett's esophagus outside of these well-structured surveillance programs.

STUDY

A retrospective analysis of a cohort of patients with Barrett's esophagus diagnosed and surveyed between 1995 and 2005 at a Veterans Affairs medical center. Data were collected on age, body mass index, and race. Patients who missed their SE by 6 months or more and those that missed their SE by twice the recommended intervals or more were identified and analyzed for changes in pathologic grades.

RESULTS

A total of 472 patients were diagnosed with Barrett's esophagus or had SE between 1995 and 2005. Three hundred and five patients only had one endoscopy and biopsy. They did not have follow-up surveillance endoscopies and biopsies. Two patients were excluded from the final analysis: one had an esophagectomy after an index diagnosis of high-grade dysplasia, and one had a diagnosis of esophageal adenocarcinoma 2 days after an initial impression of Barrett's esophagus. There were 165 patients with Barrett's metaplasia or dysplasia who had SE more than once and were included in the final analysis. Overall, 53.3% had no change in pathologic grade, 35.2% regressed to a lower pathologic grade, and 11.5% progressed to a higher grade. None (0/165, 0%) progressed to esophageal adenocarcinoma; 3.6% (6/165) progressed to high-grade dysplasia and 11.5% (19/165) regressed to normal mucosa. Forty-four patients missed their SE by 6 months or more. Of these, 50% regressed, 40.9% had no change, and 9.1% progressed. Four patients regressed to normal mucosa, one progressed to high-grade dysplasia and none progressed to esophageal adenocarcinoma. Twenty-three patients missed their SE by twice the recommended intervals or more. Of these, 60.9% regressed, 34.8% did not change, and 4.3% progressed. None progressed to esophageal adenocarcinoma or high-grade dysplasia but three regressed to normal mucosa. After adjusting for age and body mass index, patients with low-grade dysplasia are nearly seven times more likely to miss their endoscopy by twice the recommended intervals or more (OR 6.56, P-value 0.03).

CONCLUSIONS

Most veteran patients with Barrett's esophagus do not undergo surveillance endoscopies. Veteran patients with Barrett's esophagus undergoing SE rarely progress to high-grade dysplasia or esophageal adenocarcinoma. Veteran patients with Barrett's esophagus who have longer SE up to twice the recommended intervals because they missed their scheduled SE did not have a worse outcome when compared to the general Barrett's esophagus surveillance group. Veteran patients with low-grade dysplasia are most likely to miss their SE by twice the recommended intervals or more, though the reason for this is unknown.

Evaluation of quantitative image analysis criteria for the high-resolution microendoscopic detection of neoplasia in Barrett's esophagus

Early detection of neoplasia in patients with Barrett's esophagus is essential to improve outcomes. The aim of this ex vivo study was to evaluate the ability of high-resolution microendoscopic imaging and quantitative image analysis to identify neoplastic lesions in patients with Barrett's esophagus. Nine patients with pathologically confirmed Barrett's esophagus underwent endoscopic examination with biopsies or endoscopic mucosal resection. Resected fresh tissue was imaged with fiber bundle microendoscopy; images were analyzed by visual interpretation or by quantitative image analysis to predict whether the imaged sites were non-neoplastic or neoplastic. The best performing pair of quantitative features were chosen based on their ability to correctly classify the data into the two groups. Predictions were compared to the gold standard of histopathology. Subjective analysis of the images by expert clinicians achieved average sensitivity and specificity of 87% and 61%, respectively. The best performing quantitative classification algorithm relied on two image textural features and achieved a sensitivity and specificity of 87% and 85%, respectively. This ex vivo pilot trial demonstrates that quantitative analysis of images obtained with a simple microendoscope system can distinguish neoplasia in Barrett's esophagus with good sensitivity and specificity when compared to histopathology and to subjective image interpretation.

Impact of fluorodeoxyglucose PET on the management of esophageal cancer

Esophageal cancer is the third most common malignancy of the alimentary tract. The incidence of esophageal cancer has steadily increased over the past three decades. Almost all therapeutic modalities for esophageal cancer are associated with a considerable mortality and morbidity. Consequently, there has been growing concern regarding effective management of esophageal cancer. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) is playing an increasing role in the management of esophageal cancer, offering potential advantages in the accuracy of disease assessment at a number of decision points in the management pathway. This review evaluates the critical role of FDG-PET in (i) diagnosis, (ii) preoperative staging, (iii) monitoring of response to neoadjuvant therapy, (iv) assessment of recurrence and (v) prediction of prognosis of esophageal cancer. We have also compared diagnostic performance of FDG-PET and other current technologies such as computed tomography scan and endoscopic ultrasonography based on available evidence.

Clinical practice. Gastroesophageal reflux disease

A 53-year-old man, who is otherwise healthy and has a 20-year history of occasional heartburn, reports having had worsening heartburn for the past 12 months, with daily symptoms that disturb his sleep. He reports having had no dysphagia, gastrointestinal bleeding, or weight loss and in fact has recently gained 20 lb (9 kg). What would you advise regarding his evaluation and treatment?

High-resolution imaging in Barrett's esophagus: a novel, low-cost endoscopic microscope

BACKGROUND

This report describes the clinical evaluation of a novel, low-cost, high-resolution endoscopic microscope for obtaining fluorescent images of the cellular morphology of the epithelium of regions of the esophagus with Barrett's metaplasia. This noninvasive point imaging system offers a method for obtaining real-time histologic information during endoscopy.

OBJECTIVE

The objective of this study was to compare images taken with the fiberoptic endoscopic microscope with standard histopathologic examination.

DESIGN

Feasibility study.

SETTING

The University of Texas M.D. Anderson Cancer Center Department of Gastroenterology. PATIENTS, INTERVENTIONS, AND MAIN OUTCOME MEASUREMENTS: The tissue samples studied in this report were obtained by endoscopic resection from patients with previous diagnoses of either high-grade dysplasia or esophageal adenocarcinoma.

RESULTS

Three distinct tissue types were observed ex vivo with the endoscopic microscope: normal squamous mucosa, Barrett's metaplasia, and high-grade dysplasia. Squamous tissue was identified by bright nuclei surrounded by dark cytoplasm in an ordered pattern. Barrett's metaplasia could be identified by large glandular structures with intact nuclear polarity. High-grade dysplasia was visualized as plentiful, irregular glandular structures and loss of nuclear polarity. Standard histopathologic examination of study samples confirmed the results obtained by the endoscopic microscope.

LIMITATIONS

The endoscopic microscope probe had to be placed into direct contact with tissue.

CONCLUSIONS

It was feasible to obtain high-resolution histopathologic information using the endoscopic microscope device. Future improvement and integration with widefield endoscopic techniques will aid in improving the sensitivity of detection of dysplasia and early cancer development in the esophagus.

Should patients with Barrett's oesophagus be kept under surveillance? The case for

Oesophageal adenocarcinoma is associated with high mortality rates and its incidence is increasing more rapidly than any other gastrointestinal cancer in the Western world. Several factors, including gastro-oesophageal reflux disease, smoking, alcohol and male gender, are associated with oesophageal adenocarcinoma but none can be used to identify accurately those individuals who will develop adenocarcinoma. It is generally accepted that oesophageal adenocarcinoma arises predominantly in Barrett's oesophagus and it is arguable that Barrett's oesophagus is currently the only clinically useful predictor of oesophageal adenocarcinoma. Surveillance - periodic testing to detect adenocarcinoma or its precursor, high grade dysplasia - is widely recommended for patients with Barrett's oesophagus with the aim of reducing mortality from oesophageal adenocarcinoma. The annual incidence of oesophageal adenocarcinoma in patients with Barrett's oesophagus is 0.5%-1.0% although there is marked variation between studies, attributable variously to publication bias, concurrent acid suppression therapy and differences in patient characteristics. There is limited evidence that surveillance reduces the incidence of oesophageal adenocarcinoma or consequent mortality and the cause of death for patients undergoing surveillance is often unrelated to oesophageal disease. There are, nonetheless, observational studies which suggest that surveillance is associated with earlier detection of malignancy and a reduction in mortality; in addition, data from modelling studies suggest that surveillance can be cost-effective. Furthermore, the advent of new, non-surgical treatments (endoscopic mucosal resection, photodynamic therapy, argon plasma coagulation) for high grade dysplasia and early cancer has reduced the risks associated with therapy for disease detected during surveillance. Surveillance programs have high drop out rates and, for patients who continue surveillance, adherence to standard, published protocols is highly variable. The establishment of specialist Barrett's oesophagus surveillance programs, with coordinator support, has considerable potential to improve adherence to current guidelines, pending the acquisition and publication of data from ongoing studies of chemoprophylaxis and surveillance in the management of Barrett's oesophagus. In consequence, although there is a paucity of data providing unequivocal demonstration of benefit, there is no proof that surveillance is ineffective. It is, therefore, appropriate to offer surveillance for Barrett's oesophagus in accordance with locally-applicable published guidelines after a full informed discussion of the risks and benefits of surveillance and therapy; continued participation should be reviewed regularly to accommodate changes in the patient's health and expectations.

Leukocyte telomere length predicts cancer risk in Barrett's esophagus

PURPOSE

Leukocyte telomere length has gained attention as a marker of oxidative damage and age-related diseases, including cancer. We hypothesize that leukocyte telomere length might be able to predict future risk of cancer and examined this in a cohort of patients with Barrett's esophagus, who are at increased risk of esophageal adenocarcinoma and thus were enrolled in a long-term cancer surveillance program.

PATIENTS AND METHODS

In this prospective study, telomere length was measured by quantitative PCR in baseline blood samples in a cohort of 300 patients with Barrett's esophagus followed for a mean of 5.8 years. Leukocyte telomere length hazard ratios (HR) for risk of esophageal adenocarcinoma were calculated using multivariate Cox models.

RESULTS

Shorter telomeres were associated with increased esophageal adenocarcinoma risk (age-adjusted HR between top and bottom quartiles of telomere length, 3.45; 95% confidence interval, 1.35-8.78; P = 0.009). This association was still significant when individually or simultaneously adjusted for age, gender, nonsteroidal anti-inflammatory drug (NSAID) use, cigarette smoking, and waist-to-hip ratio (HR, 4.18; 95% confidence interval, 1.60-10.94; P = 0.004). The relationship between telomere length and cancer risk was particularly strong among NSAID nonusers, ever smokers, and patients with low waist-to-hip ratio.

CONCLUSION

Leukocyte telomere length predicts risk of esophageal adenocarcinoma in patients with Barrett's esophagus independently of smoking, obesity, and NSAID use. These results show the ability of leukocyte telomere length to predict the risk of future cancer and suggest that it might also have predictive value in other cancers arising in a setting of chronic inflammation.

Epidemiological trends in oesophageal cancer in the Nordic countries

OBJECTIVE

The incidence rates of oesophageal cancer vary more than those of any other cancer, world-wide. The aim of this study was to examine the epidemiological features of oesophageal cancer in the Nordic countries.

MATERIAL AND METHODS

Epidemiological data from the Nordic Cancer Registry (NORDCAN Database, http://www.ancr.nu/nordcan.asp) were used for the study analysis.

RESULTS

From 1971 to 2000 in the Nordic countries, 18,034 oesophageal cancers were detected in males and 8216 in females. In males, the incidence rates (world age standardized incidence per 100,000) of oesophageal cancer in 1971-75 and 1996-2000 were 2.7 and 6.0 in Denmark, 4.2 and 3.2 in Finland, 3.4 and 5.6 in Iceland, 2.6 and 3.3 in Norway, and 2.9 and 3.3 in Sweden, respectively. In females, the corresponding figures were: Denmark 1.1 and 1.8, Finland 3.1 and 1.3, Iceland 2.5 and 1.3, Norway 0.7 and 0.9, and Sweden 1.1 and 1.0. Each Nordic country showed a significant geographical variation in the incidence of oesophageal cancer. In both males and females the incidence curves began rising after 40 years of age, but significantly more steeply in males than in females. Over the study period, oesophageal cancer mortality increased from 2.97 to 3.68 per 100,000 in males but decreased from 1.30 to 1.08 in females. The incidence rates of oesophageal adenocarcinoma increased in males in all Nordic countries, and the increase was most marked in Denmark. The incidence of oesophageal adenocarcinoma also increased among Danish females, but compared with males, the incidence rate remained significantly lower.

CONCLUSIONS

The time trends in incidence of oesophageal cancer differ between the Nordic countries, and there has also been geographical variation within them. On a global comparison, the incidence rates of oesophageal cancer are low in the Nordic region. Oesophageal cancer is a male-predominant disease in all Nordic countries, and the incidence rates of oesophageal adenocarcinoma have increased in males and Danish females.

Reflux, Dyspepsia, and Disorders of the Foregut

Disorders of the foregut are an increasingly common cause of symptoms in Western populations. This review summarizes recent advances in the understanding and treatment of gastroesophageal reflux disease, dyspepsia and celiac disease.

Molecular Biologic Assessment of Barrett's Esophagus

BE is a prevalent condition often associated with long-standing and severe GERD. BE harbors the cellular and genetic substrates necessary for subsequent development of cancer in a subset of patients. Epidemiologically, BE patients with high-grade dysplasia exhibits the highest risk for cancer. Until recently, little was understood about which BE patients with no or low-grade dysplasia may also be at risk for progression to neoplasia. The presence of p53 abnormalities in Barrett's mucosae (such as 17p LOH) and also DNA abnormalities (such as aneuploidy and increased tetraploid fractions) detectable on flow cytometry may be useful in identifying those patients with BE who are at the highest risk for cancer development. New diagnostic modalities and therapeutic strategies continue to evolve, and will require careful clinical validation.

Is gastroesophageal reflux disease really a life-long disease: do babies who regurgitate grow up to be adults with GERD complications?

There are a number of chronic digestive diseases in adults which have symptom and/or disease onset in childhood. Examples of childhood-onset chronic diseases include Helicobacter pylori-associated gastroduodenal disease and gastroesophageal reflux disease (GERD). Unfortunately, there is a paucity of well-designed longitudinal studies that characterize the natural history of each of these conditions and more importantly identify individuals (i.e., children) who are at risk for serious, long-term adult sequelae. Gastroesophageal reflux (GER), the physiological condition, and GERD, the disease, occur frequently during the first 2 yr of life. However, commonly held "dogma" by pediatricians is the belief that the majority of these children "grew out of their GER or GERD symptoms." On the contrary, recent evidence suggests that GERD in some subjects is a chronic, potentially life-long condition that begins in childhood, and in those in whom disease onset is early, there may be a higher risk for long-term severe disease sequelae. The article by Orenstein et al., although small in cohort size (N = 19), is the first systematic, longitudinal prospective study that employs both a validated GERD symptom assessment instrument and a histological characterization of esophageal inflammation via mucosal biopsies of infants during the first year of life. The infants, part of a larger therapeutic trial, were originally referred to the investigators for GERD evaluation, failed a 2-wk lifestyle modification trial, and were randomized to placebo or intervention (acid suppression and prokinetic therapy). This placebo cohort was evaluated in follow-up via assessment of symptoms using a validated Infant-Gastroesophageal-Reflux-Questionnaire (I-GERQ) and esophageal suction biopsy; morphometric characterization of mucosal histology and symptom scores were performed at 2, 4, 6, and 12 months. At the 12-month endpoint, 10 of 19 completed the study without rescue medication and overall symptom scores improved in all 10 completers. However, none of the 10 completers had normalization of biopsy assessments, i.e., basal cell layer <25% and papillary height <53% of epithelial thickness. The authors concluded that although symptoms improved in more than half of infants with reflux esophagitis followed longitudinally, esophageal mucosal histology remained abnormal at the 1-yr evaluation in the absence of pharmacotherapy. The lack of concordant improvement of the esophageal histology should raise concern regarding sub-clinical persistence of ongoing esophageal insult, which might in the long-term, predispose the individual to GERD-related complications, such as strictures, Barrett's esophagus, and/or esophageal adenocarcinoma. In this editorial, the implications of GERD being a life-long disease based on the findings described by Orenstein et al. are discussed. In addition, a description of areas where further research is critically needed is provided namely: (1) population-based, epidemiological studies of GERD with appropriate case and control definitions, (2) characterization of genetically "at-risk" individuals (i.e., with childhood-onset GERD) for severe GERD sequelae (e.g., Barrett's esophagus, esophageal adenocarcinoma), or potentially, (3) longitudinal, family cohort natural history studies with index pediatric GERD cases.

Etiology and risk factors for oesophageal adenocarcinoma: possibilities for chemoprophylaxis?

The rapid increase in the incidence of oesophageal adenocarcinoma, particularly among white males, seems to be a true increase occurring in many parts of the industrialised world during the last few decades. Some main risk factors have been established: i.e. Barrett's oesophagus, gastrooesophageal reflux, high body mass, male sex, tobacco smoking, and high dietary intake of fruit and vegetables. Several other potential risk factors have been studied for which the evidence is less clear, including medications that relax the lower oesophageal sphincter or diets high in fat or low in nutrients from plant foods. Other factors have been found to be possibly inversely linked with the risk of oesophageal adenocarcinoma, including infection with Helicobacter pylori and anti-inflammatory drugs (such as aspirin and other non-steroidal anti-inflammatory drugs, including cyclo-oxygenase inhibitors). The methodological problem of 'confounding by indication' makes it difficult to interpret the results of anti-inflammatory drugs, and currently such medication cannot be recommended for the prevention of oesophageal adenocarcinoma. Similarly, since there is no strong evidence of a preventive effect of medical or surgical antireflux therapy with regard to risk of oesophageal adenocarcinoma, such therapy cannot be recommended in the prevention of this cancer. Although some of the known risk factors might contribute to the increasing incidence of oesophageal adenocarcinoma, the explanation that can entirely explain this striking trend remains to be identified. Oesophageal adenocarcinoma is a highly deadly cancer, but the overall prognosis and the prognosis after oesophageal cancer surgery has improved during recent years.