Barrett's Oesophagus for the Histopathologist.

1. BARRETT’S OESOPHAGUS
FOR THE
HISTOPATHOLOGIST
By
Dr. Varughese George

2. Introduction
• Replacement of the lower oesophageal squamous mucosa by metaplastic
glandular mucosa as a result of Gastro-Oesophageal Reflux Disease.
• The escalating incidence of columnar lined oesophagus (CLO) is coupled
with marked increase in the incidence of its malignant complication.
• Oesophageal cancer is
– 9th most common cancer
– 5th most common cause of cancer death.
• 8 fold increase in adenocarcinoma over the past 30 years.
• Increased incidence found in Western Europe and North America.

3. Introduction
Barrett esophagus and dysplasia appear to be precursors or markers of
adenocarcinoma development
• 10% of patients with gastroesophageal reflux will have Barrett esophagus
• 10% of patients with Barrett esophagus will have dysplasia
• 10% of patients with Barrett esophagus will have adenocarcinoma at the
time of initial diagnosis
• Longterm followup of patients with low grade dysplasia in Barrett
esophagus (Sharma 2004)
– 10% progress to high grade dysplasia
– 3% progress to carcinoma
• Followup of patients with high grade dysplasia in Barrett esophagus
(Konda 2008)
– 40% develop carcinoma
• 87% of these are intramucosal
• Only 13% are invasive into submucosa or beyond

4. A short history of Barrett’s oesophagus
• Lyall, Br J Surg 1937: “ulcers occur in the oesophagus, and are surrounded
by heterotopic gastric mucosa”
• Barrett NR, Br J Surg 1950: “chronic peptic ulcer of the oesophagus and
oesophagitis”
2 distinct lesions :
– Reflux oesophagitis
– Peptic ulcer of the oesophagus, that correspond to congenital short
oesophagus with gastric ulcer in the mediastinal stomach
• Morson & Belcher, Br J Cancer 1952: “Adenocarcinoma of the oesophagus
and ectopic gastric mucosa”

5. A short history of Barrett’s oesophagus
Some may be worried because I have changed my opinion
•The lesion should be called “the lower esophagus lined by columnar
epithelium”
•It is probably the result of a failure of the embryonic lining of the gullet to
achieve maturity.
Lord RV. Norman Barrett, “Doyen of esophageal surgery”. Ann Surg 1999;229:428.

6. Risk Factors
• Sex – male > female
• Age – middle-age
• Race – Caucasian
• Overweight
• Smoking and intake of alcohol
• Family history
• Acid reflux.
• Reflux of bile and alkali from the duodenum.
• Lack of H pylori infection of stomach encouraging a high stomach
acid level.

7. Which kind of epithelium lines
Barrett’s oesophagus?
• Initial descriptions :
– “ectopic gastric mucosa”.
– Accurate reading : “columnar cells, mucus secreting units, tubular
glands, no oxyntic cells” (Barrett 1957)
• Morson & Belcher 1952: Intestinal metaplasia
• Paull et al 1976 : Classical description of 3 types of metaplastic epithelium
• “Modern” period : Intestinal metaplasia (goblet cells) is mandatory for the
diagnosis, but...

8. Gross pathology
• Barrett’s mucosa is usually
represented by a well-defined
area of salmon-pink, velvety
mucosa similar to the adjacent
gastric mucosa.
• It has irregular margins and may
contain islands of residual
squamous, pearly white
esophageal mucosa, or it may be
ulcerated.
• It is usually limited to the lower
third of the esophagus, but in
severe cases, it may extend to the
middle and upper esophagus

9. Endoscopic Diagnosis of BE
Diagnosis – Endoscopic demonstration of at
least 3cm of columnar-lined epithelium
present in the lower oesophagus
• Long segment - Barrett's mucosa extends
more than 3cm.
• Short Segment CLO – Barrett's mucosa
extends less than 3cm.
• UltraShort Segment CLO – Barrett's
mucosa extends less than 1 cm with
microscopic demonstration of intestinal
metaplasia at the cardia.

10. Practical Diagnostic Definitions
3 types of columnar
epithelium (Paull 1976)
1. “Specialized” or
intestinal
2. Cardiac (junctional)
3. Fundic (gastric)
“Classical”: circumferential columnar epithelium >3 cm above the
oesophago-gastric junction (OGJ)
1 2 3

11. ACG and BCG criteria for Diagnosis
ACG - Extension of salmon-colored
mucosa into the tubular esophagus
extending ≥1 cm proximal to the
gastroesophageal junction with
biopsy confirmation of Intestinal
Metaplasia.
BCG - Endoscopically apparent area
above the oesophagogastric
junction that is suggestive of
Barrett’s which is supported by the
finding of columnar lined
oesophagus on histology. The
presence of areas of intestinal
metaplasia (IM), although often
present, is not a requirement for
diagnosis.
The endoscopic appearance of Barrett
esophagus showing an irregular
squamocolumnar junction with a salmon-
pink tongue extending into the tubular
esophagus.

14. •Damage to the esophageal differentiated cells in the superficial and parabasal compartments of
the esophagus.
•Basal progenitor cells move into denuded areas after the gastric acid-peptic content from the
stomach has eroded the squamous mucosa.

15. •Damage to a deeper compartment involving the squamous epithelial stem cells in the
basal compartment of the papillae.

16. •Persistent gastroesophageal reflux causes multipotential stem cells to differentiate into
columnar, mucin-secreting epithelium resistant to acid and bile.

19. •Barrett esophagus composed of a superficial, foveolar-like component (with a villiform surface)
and underlying mucous glands, which have focally split the muscularis mucosae.
•The diagnostic goblet cells are evident even at low power.

20. •High-magnification view of intestinal metaplastic epithelium of Barrett esophagus.
•Numerous goblet cells are dispersed among columnar cells.

21. •Alcian blue/periodic acid-Schiff (PAS) stain in Barrett esophagus with incomplete
metaplasia.
•The goblet cells stain intensely blue with the Alcian blue portion of the stain due to the
presence of acid mucins.
•The columnar cells between the goblet cells stain with PAS, indicating the presence of
neutral mucins.

22. • Cardiac-type mucosa in a segment of Barrett esophagus.
• When compared to the normal gastric cardia, there is atrophy of cardiac-type glands and
inflammation within the lamina propria.
• Intestinal metaplasia is seen in the adjacent mucosa.

23. Pathology and Diagnosis
• Patchwork of intestinal, cardiac
and fundic phenotypes
• No specific IHC for demonstration
of intestinal metaplasia
• MUC-1 and MUC-6 were 90%
specific for goblet cells in CLO.
• Use of
– cytokeratin 7 staining for glandular
epithelium
– cytokeratin 20 staining for surface
epithelium.

25. Pathology and Diagnosis
• Intestinal metaplasia in CLO is
preceded by development of
intermediate or ‘transitional’ type of
epithelium.
• A unique type of multilayered
epithelium is demonstrable at the
squamocolumar junction.
• Cardiac Metaplasia includes
squamous epithelium overlying the
crypts with intestinal metaplasia and
hybrid glands.
• Presence of non-goblet columar cells
that stain with Alcian Blue – blue cells
– maybe a marker for intestinal
metaplasia.

26. Pseudogoblet Cells
• Foveolar epithelial cells with
prominent cytoplasmic
distention.
• Has a hazy, ground glass
appearance to their
cytoplasmic mucin.
• Contains neutral mucin.
• Tends to aggregate in
clusters.

27. Goblet V/S Pseudogoblet Cells
In contrast to pseudogoblet cells, true
goblet cells are sparsely distributed
(arrowheads).
In contrast to pseudogoblet cells,
true goblet cells (arrowheads) have a
deeply basophilic appearance on a
PAS/AB.

28. The pathological reporting strategy for
reporting CLO ( BSG)

29. Cytology and CLO
• No generally accepted role of cytology in establishing diagnosis of CLO.
• Relies on identification of goblet cells within sheets of benign glandular
cells.
• Goblet cells exhibit a single large cytoplasmic vacuole that displaces the
nucleus, creating a crescent-shaped nucleus.
• The diameter of the vacuole is at least three times the width of a normal
columnar cell.
• Brushing cytology is a good screening tool for dysplasia.
• Unable to differentiate between dysplasia and invasive carcinoma.
• Difficult to differentiate low grade dysplasia from inflammatory changes.

30. Prague Classification

31. The Riddell’s and Vienna classification for
gastrointestinal neoplasia

32. Negative for Dysplasia
• Columnar epithelium with or without intestinal metaplasia
• The surface columnar cells are well spaced, regular, mature and have oval
to round, basally located nuclei,1-2 times the size of a mature lymphocyte

33. Negative for Dysplasia
• Columnar epithelium shows
foveolar type mucin in the
apices of the surface cells.
• Basally located, small and
ovoid nuclei.
• Sparse round cell
population in the lamina
propria.
• Mild hyperplastic features
with pseudostratied nuclei
that retain their orientation

34. Negative for Dysplasia
• Regular surface epithelium
• Apically oriented cytoplasm
and basally oriented nuclei.
• Lamina propria contains
sparse lymphocytes and
plasma cells.
• A close up of part of the
surface shows goblet cells

35. Indefinite for Dysplasia
• Histological abnormalities that meet criteria for dysplasia
but are occuring in the setting of inflammation
• Histologic abnormalities resembling dysplasia but may be
“reactive”, a result of inflammation and which would
disappear once inflammation resolves

36. Indefinite for Dysplasia
Features of dysplasia are
present:
• Nuclear enlargement and
hyerchromasia
• Focal loss of cytoplasmic
maturation
• Focal loss of basal
orientation of nuclei
Changes of dysplasia + inflammation = indefinite for dysplasia
This image of Barretts shows neutrophilic
infiltration of the surface epithelium

37. Indefinite for Dysplasia
• Neutrophils infiltrating
lamina propria and surface
epithelium
• Features of dysplasia:
– Focal loss of cytoplasmic
maturation
– Nuclear enlargement
and hyperchromasia of
surface cells
– Focal loss of basal
polarity of surface nuclei
Changes of dysplasia + inflammation = indefinite for dysplasia

39. Low Grade Dysplasia
• Enlarged, crowded, irregular,
hyperchromatic and ovoid
nuclei.
• Atypical mitoses may be
present.
• Stratification is often present.
• Architectural change including
villosity may be present.
• Loss of basal-luminal
maturation/differential axis.

41. High Grade Dysplasia
• Enlarged spheroidal nuclei
with open chromatin
pattern with nucleoli.
• Atypical mitosis are usually
present.
• Stratification with
pronounced cellular
disorganisation.
• Architectural changes
villosity, glandular budding
and complex glandular
structures is often present.
• Loss of basal-luminal
maturation/differential axis.

43. • This complex glandular proliferation shows striking cytologic atypia and represents at least
• high-grade dysplasia in Barrett esophagus.
• In some areas, the glands are back-to-back with essentially no intervening lamina propria.

44. Cytological and architectural features of
low‐grade and high‐grade dysplasia in Barrett's
oesophagus

45. Intramucosal adenocarcinoma
• Neoplastic cells make their
way to the basement
membrane , muscularis
mucosae or lamina propria.
• Effacement of architecture
of the lamina propria
• A syncytial growth pattern
may also be observed.
• Desmoplasia is absent or not
completely developed.

46. Adenocarcinoma
Nests of mucin producing cells of adenocarcinoma undermining squamous mucosa

47. Adenocarcinoma
Adenocarcinoma infiltrating as single cells (diffuse or signet ring type).
Although the cells resemble plasma cells, they are larger and many have
vacuoles.

48. Molecular Markers
• Limited utility.
• p53 labels most HGD with nuclear staining should extend to
the mucosal surface.
• Nuclear Ki-67 labeling extending to superficial cells correlates
with LGD on routine histology, whereas extensive surface
labeling correlates with HGD.
• Cyclin D1 labels up to 45% of cases.
• Beta-catenin is another useful marker for separating LGD
from reactive metaplastic changes.
• a-Methylacyl coenzyme A racemase (AMACR) was also found
useful in distinguishing reactive and dysplastic epithelium.

49. p53 Immunostaining in Barrett’s
oesophagus
p53 immunostaining of Barrett mucosa showing strong nuclear positivity and
negativity in high- and low-grade dysplasia, respectively.

52. Surveillance
• Detects neoplastic progression at an early stage and prevent
cancer-related death.
• Patients with endoscopy suggestive of BE should have 4-
quadrant biopsies at minimum intervals of every 2 cm of the
BE segment.

53. Surveillance

54. New techniques for in situ endoscopic diagnosis of neoplasia
complicating CLO

55. Summary
• Barrett’s oesophagus is an endoscopic diagnosis corroborated by histology.
• The characteristic histological features include
– Patchwork of cardiac,fundic and intestinal epithelial types
– Hybrid glands
– Multilayered epithelium
• The role of intestinal metaplasia in the neoplastic sequence of Barrett’s
oesophagus is undeniable and much more controversial in diagnosis.
• Treatment of Barrett’s oesphagus by acid suppressants cause squamous
re-epithelialisation thus causing confounding biopsy appearances.

56. Summary
• The low and high grade categories should be used by pathologists for
reporting dysplasia in CLO.
• Pathologists should use the category ‘indefinite for biopsy’ when
pathological features are equivocal due to inflammation or other features.
• Endoscopic appearances do not correlate well with histopathologic
diagnosis, thus emphasizing the need for comprehensive sampling of the
segment.
• 25-50% of high grade dysplasia have co-existent adenocarcinoma.
• The diagnosis of high grade dysplasia should be confirmed by a second
expert like a specialized gastrointestinal pathologist.

57. References
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pathogenesis. Curr Diag Pathol 2003;9:218–27.
3. Voltaggio L, Montgomery EA, Lam-Himlin D. A clinical and histopathologic
focus on Barrett esophagus and Barrett-related dysplasia. Arch Pathol Lab
Med. 2011;135:1249–1260.
4. Anjarwalla SM, Shepherd NA. Barrett’s oesophagus for the practicising
histopathologist. Recent Advances in Histopathology 22 2007;3:45-65
5. Zibadi S, Coppola D. Surgical and Molecular Pathology of Barrett
Esophagus. Cancer Control : Journal of the Moffitt Cancer Center. 22: 177-85.
6. Conteduca, V., Sansonno, D., Ingravallo, G., Marangi, S., Russi, S., Lauletta, G.,
Dammacco, F."Barrett's esophagus and esophageal cancer: An overview".
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