This document provides an overview of pathology related to the gastrointestinal tract. It describes peptic ulcers, noting their gross features such as location and size, and microscopic features including four histologic zones. Carcinoma of the stomach is also described with flat, infiltrating growth being most common grossly, and tubular and acinar patterns microscopically. Ulcerative lesions of the intestine include Cushing and Curling ulcers. Carcinoma of the colon is described as having fungating growth on the right side and a napkin-ring configuration on the left side grossly, and infiltrating glandular pattern microscopically.

1. PATHOLOGY OF THE
GASTROINTESTINAL TRACT

2. OBJECTIVES
• At the end of the session, you should know
about
• Peptic ulcer – Gross and microscopic features
• Carcinoma stomach – Gross and microscopic
features
• Ulcerative lesions of intestine
• Carcinoma colon – Gross and microscopic
features

3. DEFINITION OF ULCER
An ulcer is a discontinuity or break in a bodily
membrane that impedes normal function of the
affected organ. According to Robbins's
pathology, "ulcer is the breach of the continuity
of skin, epithelium or mucous membrane
caused by sloughing out of inflamed necrotic
tissue."

4. BENIGN ULCER V/S MALIGNANT ULCER
Features Benign ulcer Malignant ulcer

5. PEPTIC ULCER

6. PEPTIC ULCER
GROSS FEATURES
• Gastric ulcers are found
predominantly along the lesser
curvature in the region of pyloric
antrum, more commonly on the
posterior wall.
• Duodenal ulcers are commonly
found in first part of the
duodenum, more commonly on
the anterior wall.
• Peptic ulcers of either gastric or
duodenal mucosa are small (1-2.5
cm in diameter), round to oval
and punched out.
• The mucosal folds converge
towards the ulcer.
Benign chronic gastric ulcer
•Partial gastrectomy specimen is
identified by thick muscular wall and
irregular mucosal folds.
•The luminal surface shows a punched out
round to oval ulcer, about 1 cm in
diameter (arrow) penetrating into
muscularis layer.

7. PEPTIC ULCER
MICROSCOPIC FEATURES
4 histologic zones
1. Necrotic zone lies in the floor of the ulcer
• The tissue elements show coagulative
necrosis giving eosinophilic smudgy
appearance with nuclear debris.
g
2. Superficial exudative zone
• lies underneath the necrotic zone and is
composed of fibrinous exudate containin
necrotic debris and a few leucocytes,
predominantly neutrophils. Chronic peptic ulcer
Histologic zones of the ulcer are illustrated.
The mucosal surface shows necrosis,
ulceration, and inflammation.

8. PEPTIC ULCER
3. Granulation tissue zone is seen
merging into the necrotic zone.
• Composed of nonspecific chronic
inflammatory infiltrate and
proliferating capillaries.
4. Zone of cicatrisation is seen outer to
the layer of granulation tissue
• Composed of dense fibrocollagenic
scar tissue. Chronic peptic ulcer
Histologic zones of the ulcer are illustrated.
The mucosal surface shows necrosis,
ulceration, and inflammation.

9. CARCINOMA STOMACH
GROSS FEATURES
• Most common pattern is flat,
infiltrating and ulcerative growth
with irregular necrotic base and
raised margin.
• Other gross patterns include
– fungating (polypoid)
– scirrhous (linitis plastica)
– colloid (mucoid)
– ulcer cancer.
Ulcerative carcinoma stomach.
The luminal surface of the stomach in the
region of the pyloric canal shows an elevated
irregular growth with ulcerated surface and
raised margins (arrow).

10. CARCINOMA STOMACH
MICROSCOPIC FEATURES
• Tubular and acinar pattern of
growth is seen infiltrating the
stomach wall.
• The tumour invades into the wall
of stomach for variable
• depth.
• The tumour cells show varying
degree of anaplasia but is more
often poorly-differentiated with
high degree of anaplasia

11. ULCERATIVE LESIONS OF INTESTINE
Cushing ulcer
• seen in esophagus, stomach
or the duodenum.
• associated with intracranial
disease or head injury.
• caused by gastric acid
hypersecretion due to vagal
nuclei stimulation.
Curling ulcer
• seen in proximal
duodenum.
• associated with burns or
trauma.
• Caused due to reduced
blood supply and systemic
acidosis in burns or trauma.

12. CARCINOMA COLON
GROSS FEATURES
The right-sided growth, tends to be fungating,
large, cauliflower-like, soft and friable mass
projecting into the lumen.
The left-sided growth has napkin-ring
configuration it encircles the bowel wall
circumferentially with increased fibrous tissue
forming annular ring with central mucosal
ulceration.

13. CARCINOMA COLON
MICROSCOPIC FEATURES
The tumour has infiltrating glandular pattern in About 10% cases show mucin-secreting colloid
the colonic wall with varying grades of carcinoma with pools of mucin
differentiation of tumour cells.