Pathology

Gastric adenocarcinoma

• Accounts for ∼ 95% of cases

• Most commonly located on the lesser curvature

• Arises from glandular cells in the stomach

According to the Lauren classification.

• Intestinal type gastric carcinoma

  • Typically localized

  • Polypoid, glandular formation

  • Similar to an ulcerative lesion with clear raised margins

  • Commonly located on the lesser curvature

• Diffuse type gastric carcinoma

  • No clear border

  • Spreads earlier in the course of disease

  • Infiltrative growth

  • Diffuse spread in the gastric wall

  • Linitis plastica: gastric wall thickening and leather bottle appearance

  • Composed of signet ring cells: round cells filled with mucin, with a flat nucleus in the cell periphery

  • Associated with E-cadherin mutation

• Intermediate type (the least common type): should be treated as the diffuse type, as the extent of tumor infiltration is difficult to assess