Endoscopy & Histopathology

Esophageal anatomy is based on endoscopic landmarks (Prague Criteria; Sharma P et al.,
Gastroenterology 2006; 131: 1392):

  1. The tubular organ proximal to the saccular stomach is considered esophageal.
  2. the level of the endoscopic gastric type folds is considered to be the gastric cardia (Fig. 1).
  3. This classification is not based on valid anatomic criteria. In keeping with anatomy, the esophagus is that part of the foregut having submucosal glands, the stomach does not contain submucosal glands (Allison et al. Thorax 1953; 87: 90-101; Chandrasoma. Eur Surg 2006;38: 227-243).

During endoscopy the esophagus is considered normal if:

  1. the squamous lining shows absence of inflammation
  2. the squamocolumnar junction coincides with the level of the rise of the gastric type folds; this is the absence of endoscopic visible columnar lined esophagus (Fig. 1).

Drawback: endoscopic normalcy does not rule out the presence of microscopic pathology (Barrett's esophagus in 17% of GERD patients with an endoscopically normal appearing squamocolumnar junction).

During endoscopy the esophagus is considered abnormal if (see Fig. 1):

  1. the squamous lining shows inflammation (listed according to the Los Angeles classification). Biopsy sampling of inflamed squamous lining is recommended.
  2. the squamocolumnar junction does not coincide with the level of the rise of gastric type folds, this is presence of endoscopic visible columnar lined esophagus. Here histopathology comes into play and biopsies are recommended.
  3. the distal esophagus shows mucosal irregularities including rings (Schatzki Ring), webs, diverticula, tumor, ulcerations. Here histopathology comes into play and biopsies are recommended.

Drawback: biopsy sampling of an endoscopically normal appearing squamocolumnar and esophagogastric junction is not recommended. Thus premalignant Barrett's esophagus and dysplasia may be missed in 17% of GERD patients.

Figure 1: endoscopic landmarks of the current concept. Level of the rise of the gastric type folds is considered to be the gastric cardia (arrows).
* indicates level of the diaphragma. Presence of columnar lining within the tubular esophagus defines endoscopic visible columnar lined esophagus (CLE).

Currently histopathology aims to:

  1. reconfirm endoscopic visible inflammation of squamous lined esophagus.
  2. assess the presence of intestinal metaplasia within biopsies obtained from endoscopic visible columnar lined esophagus. This is Barrett's esophagus, which may progress towards GERD-induced adenocarcinoma of the esophagus (0.5% annual incidence, this is: 1 out of 10 persons with Barrett's esophagus will develop cancer in 20 years). Presence of columnar epithelium without intestinal metaplasia is currently not considered (Fig. 2).
  3. assess the presence of dysplasia and carcinoma within endoscopic visible columnar lined esophagus (CLE).

Drawback: the precursor of Barrett's esophagus is not considered (see Fig. 2) and those at risk to develop premalignant Barrett's esophagus are not identified (80-100% of GERD patients). Barrett's within dilated end stage esophagus is considered to be gastric intestinal metaplasia. For dilated end stage esophagus see novel concept.

Figure 2: Histopathology of columnar lined esophagus. The precursor of Barrett's esophagus is not considered in the current concept of GERD management. See Fig. 3 of the novel concept