Gastric carcinomaGastric carcinoma
Carcinoma is the most important and the most common (90% to 95%) of malignant tumors of the
stomach. Next in order of frequency are lymphomas (4%), carcinoids (3%), and mesenchymal tumors (2%),
* Epidemiology.•Gastric carcinoma is the second most common tumor
in the world. Its incidence, however, varies widely, being particularly high in countries such as Japan.
•Male-to-female ratio of about 2:1.
2
Gastric Cancer
Diet
H. pylori Genetic factors
* Pathogenesis of Gastric Cancer* Pathogenesis of Gastric Cancer
Precancerous changes
3
1. Helicobacter pylori Infection. 1. Helicobacter pylori Infection.
• Chronic infection with H. pylori generally
increases the risk for developing gastric
carcinoma by five- to six-fold.
• The bacterial infection causes chronic gastritis,
followed by atrophy, intestinal metaplasia,
dysplasia, and carcinoma.
2. Diet: 2. Diet:
• Nitrites derived from nitrates (preserved
food).
• Smoked and salted foods, pickled vegetables,
chili peppers.
• Lack of fresh fruit and vegetables.
3. Genetic factors: 3. Genetic factors:
• Slightly increased risk with blood group A.
• Family history of gastric cancer.
• Familial gastric carcinoma syndrome (E-cadherin
mutation).
4. Precancerous lesions:4. Precancerous lesions:
1. Gastric dysplasia:
- About 10% of these cases progress to gastric carcinoma
specially high-grade dysplasia.
2. Atrophic gastritis: which associated with intestinal
metaplasia.
3. Chronic gastric peptic ulcer.
4. Gastric adenoma.
* Morphology of gastric carcinoma: * Morphology of gastric carcinoma:
• The location of gastric carcinomas within the stomach is as
follows:
Cardia ,pylorus and antrum : 50% to 60%.
The remainder in the body and fundus: 25%
• The lesser curvature is involved in about 40% and the greater
curvature in 12%.
• Thus, a favored location is the lesser curvature of the antro
pyloric region.
* Gross morphology of gastric carcinoma:* Gross morphology of gastric carcinoma:
A. Exophytic type: forming a polypoid (fungating) mass.
B. Flat or depressed type (infiltrative):
-Localized.
-Diffuse (linnitus plastica).
C. Excavating type: forming malignant ulcer.
9
Polypoid (fungating)
10
Ulcerating (malignant ulcer)
11
Linnitus plastica
12
* Histologic subtypes of gastric carcinoma:* Histologic subtypes of gastric carcinoma:
1. Intestinal type:
- Composed of neoplastic intestinal glands resembling those of
colonic adenocarcinoma which permeate the gastric wall.
2. Diffuse type (Signet ring):
- Composed of malignant mucous cells, which generally do not
form glands, but rather permeate the gastric wall as individual
cells.
14
1. Gastric carcinoma; Intestinal type:1. Gastric carcinoma; Intestinal type:
15
1. Gastric carcinoma; Intestinal type:1. Gastric carcinoma; Intestinal type:
Gastric carcinoma: diffuse type.Gastric carcinoma: diffuse type.
16
* Complications of gastric carcinoma:* Complications of gastric carcinoma:
1. GIT bleeding.2. Gastric obstruction.3. Gastric perforation specially in the ulcerative type.4. Spread:
•Direct.•Lymphatic: especially to the left supraclavicular lymph node (Virchow’s sign).•Blood.•Transcoelomic (Krukenberg’s tumor).
* Clinical Features of gastric carcinoma:* Clinical Features of gastric carcinoma:
• Gastric carcinoma is an insidious disease that is generally
asymptomatic until late in its course.
• The symptoms include weight loss, abdominal pain, anorexia,
vomiting, altered bowel habits, and less frequently dysphagia,
anemic symptoms, and hemorrhage.
• As these symptoms are essentially non-specific, early
detection of gastric cancer is difficult.
* Diagnosis of gastric adenocarcinoma: * Diagnosis of gastric adenocarcinoma:
1. Clinical features:
2. Endoscopy: for evaluating both gross and microscopic
appearance of the tumor by taking biopsy for definitive
diagnosis.
20
References:Robbins and Cotran’s: Pathologic Basis of Disease. Seventh edition.
Top Related