Intestinal Metaplasia of the "Cardia": Accurate Differentiation of Gastric or Esophageal Origin With an Expanded Biopsy Protocol

Gastro-Esophageal Junction Precancerosis: Histological Diagnostic Approach and Pathogenetic Insights

Barrett's esophagus (BE) was initially defined in the 1950s as the visualization of gastric-like mucosa in the esophagus. Over time, the definition has evolved to include the identification of goblet cells, which confirm the presence of intestinal metaplasia within the esophagus. Chronic gastro-esophageal reflux disease (GERD) is a significant risk factor for adenocarcinoma of the esophagus, as intestinal metaplasia can develop due to GERD. The development of adenocarcinomas related to BE progresses in sequence from inflammation to metaplasia, dysplasia, and ultimately carcinoma. In the presence of GERD, the squamous epithelium changes to columnar epithelium, which initially lacks goblet cells, but later develops goblet cell metaplasia and eventually dysplasia. The accumulation of multiple genetic and epigenetic alterations leads to the development and progression of dysplasia. The diagnosis of BE requires the identification of intestinal metaplasia on histologic examination, which has thus become an essential tool both in the diagnosis and in the assessment of dysplasia's presence and degree. The histologic diagnosis of BE dysplasia can be challenging due to sampling error, pathologists' experience, interobserver variation, and difficulty in histologic interpretation: all these problems complicate patient management. The development and progression of Barrett's esophagus (BE) depend on various molecular events that involve changes in cell-cycle regulatory genes, apoptosis, cell signaling, and adhesion pathways. In advanced stages, there are widespread genomic abnormalities with losses and gains in chromosome function, and DNA instability. This review aims to provide an updated and comprehensible diagnostic approach to BE based on the most recent guidelines available in the literature, and an overview of the pathogenetic and molecular mechanisms of its development.

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.