Achalasia and associated esophageal cancer risk: What lessons can we learn from the molecular analysis of Barrett's-associated adenocarcinoma?

Intercellular crosstalk between cancer cells and cancer-associated fibroblasts via exosomes in gastrointestinal tumors

Gastrointestinal (GI) tumors are a significant global health threat, with high rates of morbidity and mortality. Exosomes contain various biologically active molecules like nucleic acids, proteins, and lipids and can serve as messengers for intercellular communication. They play critical roles in the exchange of information between tumor cells and the tumor microenvironment (TME). The TME consists of mesenchymal cells and components of the extracellular matrix (ECM), with fibroblasts being the most abundant cell type in the tumor mesenchyme. Cancer-associated fibroblasts (CAFs) are derived from normal fibroblasts and mesenchymal stem cells that are activated in the TME. CAFs can secrete exosomes to modulate cell proliferation, invasion, migration, drug resistance, and other biological processes in tumors. Additionally, tumor cells can manipulate the function and behavior of fibroblasts through direct cell-cell interactions. This review provides a summary of the intercellular crosstalk between GI tumor cells and CAFs through exosomes, along with potential underlying mechanisms.

Endoscopic Surveillance in Idiopathic Achalasia

Idiopathic achalasia is a rare esophageal dysmotility disorder of unknown etiology with only palliative treatment available. Many studies have established a significantly increased risk of esophageal cancer in patients with achalasia. However, current guidelines advise against routine surveillance due to low absolute risk and a paucity of high-quality evidence and cost-effectiveness assessments. This review aims to assess the need for routine endoscopic surveillance in achalasia based on a growing body of literature calling in support of it, mainly due to the increased risk of esophageal cancer. We searched PubMed and Google Scholar electronic databases for articles within the last 10 years using the keywords 'achalasia', 'cancer,' 'neoplasms,' 'screening,' and 'surveillance.' After excluding pseudoachalasia/secondary achalasia, other esophageal dysmotility disorders, and associations with malignancies outside the esophagus, we selected 31 articles for this review. Through these articles, we identified areas of focus for ongoing and future research that may result in significant risk reduction of complications, including esophageal cancer and beyond.

The patient characteristics of esophageal carcinoma following laparoscopic myotomy for esophageal achalasia

BACKGROUND

It is common knowledge that esophageal achalasia patients have a high risk of developing esophageal carcinoma. The present study assessed the characteristics of esophageal carcinoma patients following laparoscopic Heller-Dor surgery (LHD) for esophageal achalasia.

METHOD

Among 622 cases which were esophageal achalasia patients and underwent LHD as the primary surgery, we compared the patient background, pathophysiology, symptoms, and surgical outcomes according to whether or not esophageal carcinoma occurred following surgery.

RESULTS

Six cases (0.96%) of postoperative esophageal carcinoma were confirmed. The characteristics of the cases in which esophageal carcinoma occurred were older age, longer disease duration (p = 0.0362 and 0.0028, respectively), decreased sphincter pressure of the lower esophagus, a high rate of sigmoid esophagus, and a long esophagus lateral diameter (p = 0.0214, 0.001, and 0.0416, respectively). Moreover, no differences in surgical outcomes were confirmed and there were no differences in symptoms from before and following surgery.

CONCLUSION

The characteristics of esophageal carcinoma patients with achalasia following laparoscopic myotomy were an older age, longer disease duration, and greater progression of disease pathophysiology.

HOXA13 in etiology and oncogenic potential of Barrett's esophagus

Barrett's esophagus in gastrointestinal reflux patients constitutes a columnar epithelium with distal characteristics, prone to progress to esophageal adenocarcinoma. HOX genes are known mediators of position-dependent morphology. Here we show HOX collinearity in the adult gut while Barrett's esophagus shows high HOXA13 expression in stem cells and their progeny. HOXA13 overexpression appears sufficient to explain both the phenotype (through downregulation of the epidermal differentiation complex) and the oncogenic potential of Barrett's esophagus. Intriguingly, employing a mouse model that contains a reporter coupled to the HOXA13 promotor we identify single HOXA13-positive cells distally from the physiological esophagus, which is mirrored in human physiology, but increased in Barrett's esophagus. Additionally, we observe that HOXA13 expression confers a competitive advantage to cells. We thus propose that Barrett's esophagus and associated esophageal adenocarcinoma is the consequence of expansion of this gastro-esophageal HOXA13-expressing compartment following epithelial injury.

Impact of Environmental and Pharmacologic Changes on the Upper Gastrointestinal Microbiome

Diseases of the upper gastrointestinal tract have become more prevalent over time. Mechanisms of disease formation are still only partially understood. Recent literature has shown that the surrounding microbiome affects the propensity for disease formation in various parts of the upper gastrointestinal tract. A review was performed of any literature to our best knowledge concerning the effects of pharmacologic agents, environmental changes, and surgical intervention on the microbiome of the upper gastrointestinal tract. Searches of the literature were performed using specific keywords related to drugs, surgical procedures, and environmental factors. Many prescription and nonprescription drugs that are commonly used have varying effects on the upper gastrointestinal tract. Proton pump inhibitors may affect the relative prevalence of some organisms in the lower esophagus and have less effect in the proximal esophagus. Changes in the esophageal microbiome correlate with some esophageal diseases. Drugs that induce weight loss have also been shown to affect the microbiomes of the esophagus and stomach. Common surgical procedures are associated with shifts in the microbial community in the gastrointestinal tract. Environmental factors have been shown to affect the microbiome in the upper gastrointestinal tract, as geographic differences correlate with alterations in the microbiome of the gastrointestinal tract. Understanding the association of environmental and pharmacologic changes on the microbiome of the upper gastrointestinal tract will facilitate treatment plans to reduce morbidity from disease.

The Mechanisms for the Association of Cancer and Esophageal Dysmotility Disorders

BACKGROUND

Achalasia and other esophageal dysmotility disorders mimicking achalasia can be associated with cancer. This study aimed to review the main mechanisms for which cancer may develop in esophageal dysmotility disorder patients.

METHODS

A narrative review was performed.

RESULTS

The mechanism for developing squamous cell carcinoma and adenocarcinoma are discussed. Besides, achalasia-like syndromes related to familial KIT-gene mutation and pseudoachalasia are discussed.

CONCLUSIONS

Knowing the main mechanism for which achalasia can be related to cancer is essential for clinicians to conduct the proper investigation, surveillance, and treatment.

Risk of Squamous Cell Carcinoma and Adenocarcinoma of the Esophagus in Patients With Achalasia: A Long-Term Prospective Cohort Study in Italy

INTRODUCTION

Epidemiological studies assessing relative risk and incidence rate of esophageal cancer in patients with achalasia are scarce. We performed a long-term prospective cohort study to evaluate the risk of both squamous cell carcinoma and adenocarcinoma of the esophagus in these patients.

METHODS

Between 1973 and 2018, patients with primary achalasia were followed by the same protocol including upper endoscopy with esophageal biopsies. Standardized incidence ratios (SIRs) with 95% confidence interval (CI) were used to estimate the relative risk of esophageal cancer in patients with achalasia compared with the sex- and age-matched general population.

RESULTS

A cohort of 566 patients with achalasia (46% men, mean age at diagnosis: 48.1 years) was followed for a mean of 15.5 years since the diagnosis of achalasia. Overall, 20 patients (15 men) developed esophageal cancer: 15 squamous cell carcinoma and 5 adenocarcinoma. The risk of esophageal cancer was significantly greater than the general population (SIR 104.2, 95% CI 63.7-161), and this for both squamous cell carcinoma (SIR 126.9, 95% CI 71.0-209.3) and adenocarcinoma (SIR 110.2, 95% CI 35.8-257.2). The excess risk was higher in men than women. Annual incidence rate of esophageal cancer was only 0.24% and was higher for squamous cell carcinoma (0.18%) than adenocarcinoma (0.06%).

DISCUSSION

Patients with achalasia have an excess risk of developing both squamous cell carcinoma and adenocarcinoma of the esophagus; however, this prospective cohort study confirms that the annual incidence of esophageal cancer is rather low. These findings may have implications for endoscopic surveillance of patients with achalasia.

Evaluation of Gastroesophageal Reflux Disease 1 Year after Esophageal Atresia Repair: Paradigms Lost from a Single Snapshot?

OBJECTIVE

To analyze the findings of both multichannel intraluminal impedance with pH (MII-pH) and endoscopy/histopathology in children with esophageal atresia at age 1 year, according to current recommendations for the evaluation of gastroesophageal reflux disease (GERD) in esophageal atresia.

STUDY DESIGN

We retrospectively reviewed both MII-pH and endoscopy/histopathology performed in 1-year-old children with esophageal atresia who were followed up in accordance with international recommendations. Demographic data and clinical characteristics were also reviewed to investigate factors associated with abnormal GERD investigations.

RESULTS

In our study cohort of 48 children with esophageal atresia, microscopic esophagitis was found in 33 (69%) and pathological esophageal acid exposure on MII-pH was detected in 12 (25%). Among baseline variables, only the presence of long-gap esophageal atresia was associated with abnormal MII-pH. Distal baseline impedance was significantly lower in patients with microscopic esophagitis, and it showed a very good diagnostic performance in predicting histological changes.

CONCLUSIONS

Histological esophagitis is highly prevalent at 1 year after esophageal atresia repair, but our results do not support a definitive causative role of acid-induced GERD. Instead, they support the hypothesis that chronic stasis in the dysmotile esophagus might lead to histological changes. MII-pH may be a helpful tool in selecting patients who need closer endoscopic surveillance and/or benefit from acid suppression.

Investigation of oral, gastric, and duodenal microbiota in patients with upper gastrointestinal symptoms

Disease-associated alterations of the intestinal microbiota composition, known as dysbiosis, have been well described in several functional gastrointestinal (GI) disorders. Several studies have described alterations in the gastric microbiota in functional dyspepsia, but very few have looked at the duodenum.Here, we explored the upper GI tract microbiota of inpatients with upper GI dyspeptic symptoms, and compared them to achalasia controls, as there is no indication for an esophagogastroduodenoscopy in healthy individuals.We found differences in the microbiota composition at the three sites evaluated (ie, saliva, stomach and duodenum). Changes observed in patients with dyspepsia included an increase in Veillonella in saliva, an oral shift in the composition of the gastric microbiota, and to some degree in the duodenum as well, where an important abundance of anaerobes was observed. Metabolic function prediction identified greater anaerobic metabolism in the stomach microbial community of patients with dyspepsia. Proton pump inhibitor use was not associated with any particular genus. Co-abundance analysis revealed Rothia as the main hub in the duodenum, a genus that significantly correlated with the relative abundance of Clostridium, Haemophilus, and ActinobacillusWe conclude that patients with upper GI symptoms consistent with dyspepsia have alterations in the microbiota of saliva, the stomach, and duodenum, which could contribute to symptoms of functional GI disorders.

Esophagobronchial fistula complicated by esophageal achalasia treated by per-oral endoscopic myotomy

A 48-year-old man who underwent balloon dilation for esophageal achalasia more than 20 years prior developed severe dysphagia and cough during mealtimes. Endoscopic findings showed a markedly dilated esophagus with residue, narrowing of the esophagogastric junction (EGJ), and a fistula in the middle thoracic esophagus. Esophagography showed narrowing of the EGJ and outflow of contrast from the esophagus to the bronchus. In addition, computed tomography showed marked esophageal dilatation and diffuse granular shading in both lungs. Based on these imaging findings, the patient was diagnosed with deterioration of esophageal achalasia and an esophagobronchial fistula (EBF) secondary to achalasia. The increased intra-esophageal pressure caused by the achalasia was suspected to have inhibited the closure of the EBF. Therefore, we believed that per-oral endoscopic myotomy (POEM) would help treat the achalasia and simultaneously contribute to closing of the EBF. Immediately after POEM, the dysphagia and cough improved. Furthermore, the EBF was closed. 14 months after POEM, the patient did not exhibit deterioration of esophageal achalasia and EBF. To the best of our knowledge, there have been no reports of POEM implemented in cases of esophageal achalasia complicated by EBF. Therefore, this case is worth reporting.