Is There an Increasing Incidence of Gastroesophageal Junctional Adenocarcinoma and Barrett Esophagus in Asia? A Review of Diagnostic Conundrums

<b><i>Background:</i></b> Epidemiology data of gastroesophageal junction (GEJ) cancers in Asia are extremely scarce. It is hardly registered by any cancer registry in the region, and only a few reports are available. Based on existing literature works, the overall trend indicates similar or gradually increasing GEJ cancers in Asia but comparably less than the West. The increasing trend in Asia is likely a result of rising risk factors, especially of gastroesophageal reflux disease and obesity. <b><i>Summary:</i></b> However, epidemiology data may be misleading due to several contentious diagnostic issues. The diagnostic conundrums are due to inherent complexity of the GEJ as a functional and pathological unit. Challenging diagnostic issues in Asia include the following: nonstandardized landmark of the GEJ, misclassification of Barrett esophagus, targeted versus nontargeted tissue sampling, histopathology disagreement and challenges in screening or surveillance of dysplastic BE and early GEJ cancer. The recent Asian-Pacific survey led by the Asian Barrett Consortium (ABC) has provided useful insights into these contentious issues. A key learning point from these diagnostic limitations is that the awareness of the disease and adherence to existing recommendations or guidelines are poor in the region. <b><i>Key Messages:</i></b> Standardization in diagnostic methodology is vital for accurate epidemiology data, and this can only come from better awareness and adherence through educational and international efforts. Last, surveillance strategy may need a paradigm shift from a purely diagnostic approach to a combined targeted surveillance and treatment approach using novel endoscopic techniques.

Esophageal granular cell tumor and eosinophils: a multicenter experience

Background Esophageal granular cell tumor (eGCT) is rare, and the recent literature suggests a link between eosinophilic esophagitis (EoE) and eGCT. The aim of our study was to determine if EoE or other disorders associated with eosinophilia are consistently associated with eGCT. Methods We retrospectively searched pathology databases of three academic institutions from 1999 to 2018 for eGCTs. The archived slides and medical records were reviewed. Results From 294,855 esophagogastroduodenoscopy procedures, 45 patients (17 males and 28 females) with eGCTs were identified. The patients (30–73 years in age, median 50) had eGCT 0.2–2.0 cm in size (average 0.71). Thirteen had a history of gastroesophageal reflux disease, 5 had Barrett esophagus/goblet cell metaplasia and 1 had EoE. Thirty-four eGCTs had intralesional eosinophils (14 with peak > 10 eosinophils/400x hpf); of these, 21 also had eosinophils in lamina propria (9 with peak > 10 eosinophils/hpf). eGCT with atypical features (including nuclear enlargement and prominent nucleoli) were more likely to have increased eosinophils in non-epithelial compartments than those without atypia. Pleomorphism and spindled cells were seen in 3 eGCT cases (mean peak intralesional eosinophils: 43 per hpf); 2 of these had goblet cell metaplasia. We found no association between EoE and eGCT, p = 0.5966, (95% C.I. 0.0276, 6.5389, Fisher’s exact test). Instead, most patients had gastroesophageal reflux disease or Barrett esophagus. Conclusion Eosinophilia, common in eGCT and adjacent stroma, likely drives atypical/reactive histologic features, but a pathogenic relationship between eosinophil rich inflammatory conditions and eGCT has not yet been established.

Clonal transitions and phenotypic evolution in Barrett's oesophagus

Background & Aims: Barrett esophagus (BE) is a risk factor for the development of esophageal adenocarcinoma, however our understanding of how Barrett esophagus evolves is still poorly understood. We demonstrate that dynamic clonal phenotypic changes occur at the gland level, the mechanism by which these changes evolve, and how diversity may play a role in progression. Methods: We analyzed the distribution and diversity of gland phenotype between and within BE biopsies and the background mucosa of those that had progressed to dysplasia or developed BE post-esophagectomy, using immunohistochemistry and H&E analysis. Clonal relationships between distinct gland types were determined by laser capture microdissection sequencing of the mitochondrial genome. Results: Five different non-dysplastic gland phenotypes were identified in a cohort of 64 patients; most non-dysplastic patients showed a single gland phenotype per biopsy but some showed two or three gland types. We reveal a shared common ancestor between parietal cell-containing oxynto-cardiac glands and goblet cell-containing specialized Barrett glands through a shared somatic mtDNA mutation. We also reveal a similar relationship between specialized and cardiac-type glands, and specialized and Paneth cell-containing glands. Clonal-related distinct within gland phenotypes were also observed. The diversity of gland types was significantly increased adjacent to dysplasia compared to non-dysplastic BE and patients with post-esophagectomy BE, suggesting that gland diversity evolves in BE patients over time. Conclusions: We have shown that the range of BE phenotypes represent an evolutionary process and that changes in gland diversity may play a role in progression. Furthermore, we demonstrate common ancestry between gastric and intestinal glands in BE.