Cardiac Metaplasia: Follow, Treat, or Ignore?

Clinicopathological significance of intestinal metaplasia in endoscopically resected early gastric carcinoma

OBJECTIVE

To investigate the clinicopathological and prognostic significance of intestinal metaplasia (IM) in endoscopically resected early gastric carcinoma (EGC).

METHODS

Altogether 136 consecutive cases with EGC resected by endoscopic submucosal dissection over 5 years were included and divided into the early gastric cardiac (EGCC; n = 60) and non-cardiac carcinoma (EGNCC; n = 76) groups. Goblet cell IM and subtypes were determined with histology and immunostaining. Recurrence-free survival (RFS) was compared among various IM groups.

RESULTS

IM was identified in 128 (94.1%) EGC cases, including complete IM (n = 39), incomplete IM (n = 27), and mixed IM (n = 62). Incomplete IM was significantly more common in EGCC and exhibited a lower frequency of en bloc resection than the complete subtype. The frequency of synchronous or metachronous gastric tumor was significantly more common in EGCC with complete IM than in those with incomplete IM. Compared to EGC without IM, EGC with IM showed a significantly higher frequency of non-poorly cohesive carcinoma, en bloc resection, and non-eCuraC-1 grade. EGNCC with IM was significantly associated with negative resection margins and en bloc resection. The 5-year RFS was significantly lower in EGNCC patients with incomplete IM compared with those with mixed IM. The independent risk factors for RFS included tumor size >2 cm and eCuraC-1 grade.

CONCLUSIONS

Subtyping IM in EGC helped predict endoscopic resectability, prognosis, and risk of synchronous or metachronous gastric tumor. The significance of IM differed between EGCC and EGNCC. Large studies with longer follow-up are warranted to validate our findings.

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSIONS

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

One stomach, two subtypes of carcinoma-the differences between distal and proximal gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors of the digestive tract, posing a significant risk to human health. Over the past 10 years, the pathological characteristics and the prognosis of GC have been determined based on the locations of the tumors that were then classified into two types-proximal and distal GC. This review focuses on the differences in epidemiology, etiology, cell source, pathological characteristics, gene expression, molecular markers, manifestations, treatment, prognosis, and prevention between proximal and distal GC to provide guidance and a basis for clinical diagnosis and treatment.

The Meaning of Incidental Goblet Cells at the Gastroesophageal Junction

BACKGROUND AND AIMS

The causes for the occurrence of goblet cells at the gastroesophageal junction (GEJ-GC) are unknown. The aim of our study was to compare the concurrent histologic changes of the stomach in (1) patients with GEJ-GC, but without Barrett's esophagus (BE) to those in (2) patients with BE and in (3) controls without GEJ-GC or BE.

METHODS

We used an electronic database of histopathologic records from 1.3 million individual patients, who underwent esophago-gastro-duodenoscopy (EGD) in 2009-2018. We compared the prevalence of Helicobacter pylori-positive gastritis (HpG), gastric intestinal metaplasia (G-IM), chronic inactive gastritis (CIG), and reactive gastropathy (RG) among the 3 patient groups, using odds ratios and their 95% confidence intervals.

RESULTS

Of all EGD patients, 4.0% harbored BE and 2.4% GEJ-GC. The average age of patients with GEJ-GC (60 ± 14) was significantly younger than the age of patients with BE (63 ± 12) and significantly older than the age of controls (55 ± 17). Female subjects were more common among GEJ-GC (54%) than BE (37%), but less common than among controls (63%). The 3 gastric histopathology changes associated with H. pylori were significantly more common in GEJ-GC than BE (for HpG 2.42, 2.29-2.56; for G-IM 1.82, 1.73-1.92; for CIG 1.31, 1.22-1.41). The corresponding differences between GEJ-GC and controls were less striking (for HpG 0.97, 0.93-1.01; for G-IM 1.15, 1.11-1.19; for CIG 0.90, 0.85-0.95). RG was slightly less common in GEJ-GC than BE (0.89, 0.86-0.92) and controls (0.94, 0.91-0.96).

CONCLUSIONS

With respect to its demographic and histopathologic features, GEJ-GC likely represents gastric intestinal metaplasia as opposed to BE and should prompt gastric intestinal metaplasia screening and management.

Histologic Study of the Esophagogastric Junction of Organ Donors Reveals Novel Glandular Structures in Normal Esophageal and Gastric Mucosae

INTRODUCTION

Whether cardiac mucosa at the esophagogastric junction is normal or metaplastic is controversial. Studies attempting to resolve this issue have been limited by the use of superficial pinch biopsies, abnormal esophagi resected typically because of cancer, or autopsy specimens in which tissue autolysis in the stomach obscures histologic findings.

METHODS

We performed histologic and immunohistochemical studies of the freshly fixed esophagus and stomach resected from 7 heart-beating, deceased organ donors with no history of esophageal or gastric disease and with minimal or no histologic evidence of esophagitis and gastritis.

RESULTS

All subjects had cardiac mucosa, consisting of a mixture of mucous and oxyntic glands with surface foveolar epithelium, at the esophagogastric junction. All also had unique structures we termed compact mucous glands (CMG), which were histologically and immunohistochemically identical to the mucous glands of cardiac mucosa, under esophageal squamous epithelium and, hitherto undescribed, in uninflamed oxyntic mucosa throughout the gastric fundus.

DISCUSSION

These findings support cardiac mucosa as a normal anatomic structure and do not support the hypothesis that cardiac mucosa is always metaplastic. However, they do support our novel hypothesis that in the setting of reflux esophagitis, reflux-induced damage to squamous epithelium exposes underlying CMG (which are likely more resistant to acid-peptic damage than squamous epithelium), and proliferation of these CMG as part of a wound-healing process to repair the acid-peptic damage could result in their expansion to the mucosal surface to be recognized as cardiac mucosa of a columnar-lined esophagus.

Pathogenesis and Cells of Origin of Barrett's Esophagus

In patients with Barrett's esophagus (BE), metaplastic columnar mucosa containing epithelial cells with gastric and intestinal features replaces esophageal squamous mucosa damaged by gastroesophageal reflux disease. This condition is estimated to affect 5.6% of adults in the United States, and is a major risk factor for esophageal adenocarcinoma. Despite the prevalence and importance of BE, its pathogenesis is incompletely understood and there are disagreements over the cells of origin. We review mechanisms of BE pathogenesis, including transdifferentiation and transcommitment, and discuss potential cells of origin, including basal cells of the squamous epithelium, cells of esophageal submucosal glands and their ducts, cells of the proximal stomach, and specialized populations of cells at the esophagogastric junction (residual embryonic cells and transitional basal cells). We discuss the concept of metaplasia as a wound-healing response, and how cardiac mucosa might be the precursor of the intestinal metaplasia of BE. Finally, we discuss shortcomings in current diagnostic criteria for BE that have important clinical implications.

Barretts's carcinogenesis

Barrett's esophagus is considered a precancerous lesion of esophageal adenocarcinoma (EAC). Long‐segment Barrett's esophagus, which is generally associated with intestinal metaplasia, has a higher rate of carcinogenesis than short‐segment Barrett's esophagus, which is mainly composed of cardiac‐type mucosa. However, a large number of cases reportedly develop EAC from the cardiac‐type mucosa which has the potential to involve intestinal phenotypes. There is no consensus regarding whether the definition of Barrett's epithelium should include intestinal metaplasia. Basic researches using rodent models have provided information regarding the origins of Barrett's epithelium. Nevertheless, it remains unclear whether differentiated gastric columnar epithelium or stratified esophageal squamous epithelium undergo transdifferentiation into the intestinal‐type columnar epithelium, transcommittment into the columnar epithelium, or whether the other pathways exist. Reflux of duodenal fluid including bile acids into the stomach may occur when an individual lies down after eating, which could cause the digestive juices to collect in the fornix of the stomach. N‐nitroso‐bile acids are produced with nitrites that are secreted from the salivary glands, and bile acids can drive expression of pro‐inflammatory cytokines via EGFR or the NF‐κB pathway. These steps may contribute significantly to carcinogenesis.

Intestinal metaplasia of the gastric cardia: findings in patients with versus without Barrett's esophagus

BACKGROUND AND AIMS

There is controversy about finding intestinal metaplasia (IM) of the gastric cardia on biopsy. The most recent American College of Gastroenterology guideline comments that IM cardia is not more common in patients with Barrett's esophagus (BE). It provides limited guidance on whether the cardia should be treated when patients with BE undergo endoscopic eradication therapy (EET) and whether the cardia should undergo biopsy after ablation. The aims of our study were to determine the frequency in the proximal stomach of (1) histologic gastric cardia mucosa and (2) IM cardia. A third aim was to explore the frequency of advanced pathology (dysplasia and adenocarcinoma) in the cardia after patients with BE have undergone EET.

METHODS

Consecutive patients undergoing esophagogastroduodenoscopy between January 2008 and December 2014 who had proximal stomach biopsies were included. Patients who had histologically confirmed BE were compared with those without BE.

RESULTS

Four hundred sixty-two patients, 289 with BE and 173 without BE, were included. Histologically confirmed cardiac mucosa was found in 81.6% of all patients. This was more frequent in those with versus without BE (86% vs 75%; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.28-3.32; P = .003). IM cardia was more common in the BE group (17% vs 7%; OR, 2.67; 95% CI, 1.38-5.19; P = .004). Advanced pathology was more likely in the patients with BE who had undergone EET.

CONCLUSIONS

Cardiac mucosa is present in most patients who undergo endoscopy for upper GI symptoms. IM cardia is more common in patients with BE than those without. Advanced histologic changes in the cardia were seen only in the subgroup of patients with BE who had undergone EET.