GASTRIC CARCINOMA

Anatomy

Stomach begins at GE junction, ends at duodenum.

3 parts- uppermost is cardia, largest part in middle is body, the last part is pylorus.

Cardia contains mucin producing cells.

Fundus or body mucoid cells, chief cells, parietal cells.

Pylorus has mucin producing cells.

Five layers: Mucosa, submucosa, muscular layer, subserosal layer, serosal layer.

Peritoneum of greater sac covers anterior surface

A portion of lesser sac drapes posteriorly over stomach.

The GE junction has limited serosal covering.

Pathophysiology

Understand vascular supply, allows for understanding of routes of spread.

Derived from celiac artery.

Left gastric supplies upper right stomach.

Right gastric off common hepatic- lower portion.

Right gastroepiploic -lower portion of greater curve.

Understanding lymphatic drainage can clarify nodal involvement.

Complex drainage

Primarily along celiac axis.

Minor drainage along splenic hilum, suprapancreatic nodal groups, porta hepatis, and gastroduodenal areas

History

Early disease has no symptoms, some patients with incidental complaints get an early diagnosis.

If symptoms, it reflects advanced disease; These may include indigestion, nausea, dysphagia, early satiety, anorexia, weight loss.

Late complications include: pleural effusions, peritoneal effusions, GOO, GE obstruction, SBO, bleeding, jaundice, cachexia.

Physical

All physical signs are late events.

Too late for curative procedures.

Palpable stomach with succussion splash, hepatomegaly, Virchow nodes, sister MJ nodes, Blumer shelf, weight loss, pallor from bleeding and anemia.

Histology

Adenocarcinoma is classified according to the most unfavorable microscopic element present: tubular, papillary, mucinous, signet-ring cells.

Also identified by gross appearance: ulcerative, polypoid, scirrous, superficial spreading, multicentric, or Barrett ectopic.

Variety of other schemes: Borrmann, Lauren.

Borrmann Classification

5 categories

Type I: polypoid or fungating

Type II: ulcerating lesions with elevated borders

Type III: ulceration with invasion of wall

Type IV: diffuse infiltration

Type V: cannot be classified

Lauren System

Epidemic or endemic

The intestinal, expansive epidemic type gastric cancer is associated with atrophic gastritis, retained glandular structure, little invasiveness, sharp margins. It would be a Borrmann I or II.

The epidemic or Borrmann I or II carries better prognosis, shows no family history.

The diffuse, infiltrative, endemic, is poorly differentiated, with dangerously deceptive margins, invades large areas of stomach. Younger patients, genetic factors, blood groups, and family history.

by

Akshaya Srikanth

Pharm.D*

India