69- Hematoxylin and eosin stained sections after the blocking of
specimen. - Light microscope.
3 Methods
World Health Organization (WHO) classification of tumor defines
adenocarcinoma of esophagus as malignant epithelial tumor with
glandular differentiation. It classifies the adenocarcinoma into pre-
invasive type (dysplasia), adenocarcinoma as well as the salivary
gland type carcinoma: adenoid cystic carcinoma, adenosquamous
carcinoma, and mucoepidermoid carcinoma [ 4 ] (see Note 1). The
most often accounted histology should be adenocarcinoma.4 Notes
- (A) Dysplasia (intraepithelial neoplasia)
Majority of esophageal adenocarcinomas has the etiology
of GORD. The first morphological feature that is labeled as
precursor of esophageal adenocarcinoma is the presence of
Barrett esophagus. The Barrett esophagus is a metaplastic pro-
cess in which the squamous epithelium of the esophagus is
replaced by the columnar epithelium.
The definition of Barrett esophagus depends on the endo-
scopically visible metaplastic columnar epithelium 1 cm above
esophagogastric junction and the presence of intestinal meta-
plasia in biopsy taken above the esophagogastric junction [ 5 ].
Intestinal metaplasia means identification of goblet cells
(Fig. 1 ).
Adenocarcinoma of esophagus could develop from Barrett
esophagus. The presence of Barrett esophagus will prone the
clinicians for close follow-up and repeated endoscopic exami-
nation for detection of dysplasia, which is the precursor of
adenocarcinoma. There are numerous studies and animal
models (see chapter 13 ) proving and demonstrating the changes
in genetic profiles from Barrett esophagus to dysplasia and
esophageal adenocarcinoma [ 6 ].
3.1 Determining
the Subtypes
of Esophageal
Adenocarcinoma
3.2 For
Adenocarcinoma,
Determine the Grading
and Histological
Variants (See Note 2)
3.3 Awareness
and Assessment
of the Treatment Effect
of Preoperative
Therapies (See Note 3)
Pathology of Esophageal Adenocarcinoma