What are the two main histologic types of gastric adenocarcinoma and their features?

What are the two main histologic types of gastric adenocarcinoma and their features?

• A. Papillary type and mucinous type.
• B. Clear cell type and signet-ring type.
• C. Small cell carcinoma and large cell carcinoma.
• D. Intestinal type (gland-forming, cohesive cells) and diffuse type (signet-ring cells with diffuse infiltration; linitis plastica).

Answer: (D)

The main distinction in gastric adenocarcinoma is the Lauren classification: intestinal type and diffuse type. The intestinal type forms gland-forming, cohesive cells that resemble intestinal epithelium and often arises on a background of chronic gastritis with intestinal metaplasia; it tends to grow as recognizable glands and can have a relatively variable prognosis. The diffuse type is characterized by discohesive cells infiltrating the stomach wall, frequently containing signet-ring cells with mucin pushing the nucleus to the periphery; this pattern leads to widespread, infiltrative spread and thickening of the stomach wall known as linitis plastica, typically with a poorer prognosis and little or no gland formation. The other named options don’t describe this two-pattern framework that defines gastric adenocarcinoma morphology.

The main distinction in gastric adenocarcinoma is the Lauren classification: intestinal type and diffuse type. The intestinal type forms gland-forming, cohesive cells that resemble intestinal epithelium and often arises on a background of chronic gastritis with intestinal metaplasia; it tends to grow as recognizable glands and can have a relatively variable prognosis. The diffuse type is characterized by discohesive cells infiltrating the stomach wall, frequently containing signet-ring cells with mucin pushing the nucleus to the periphery; this pattern leads to widespread, infiltrative spread and thickening of the stomach wall known as linitis plastica, typically with a poorer prognosis and little or no gland formation. The other named options don’t describe this two-pattern framework that defines gastric adenocarcinoma morphology.