Distinguish intestinal-type and diffuse-type gastric adenocarcinoma histologically.

Distinguish intestinal-type and diffuse-type gastric adenocarcinoma histologically.

• A. Intestinal type forms gland-like structures; diffuse-type shows signet-ring cells with diffuse infiltration (linitis plastica).
• B. Diffuse type forms gland-like structures; intestinal type shows signet-ring cells.
• C. Both types form gland-like structures; only difference is location.
• D. Neither forms glandular structures.

Answer: (A)

The main histologic distinction is gland formation. Intestinal-type gastric adenocarcinoma tends to organize into gland-like structures that resemble intestinal epithelium, with cohesive neoplastic cells forming tubules and glands. Diffuse-type, on the other hand, lacks these glands and infiltrates the stomach wall as individual, discohesive cells, often with signet-ring morphology where mucin pushes the nucleus to the cell's periphery. This diffuse infiltration can cause thickening and rigidity of the stomach known as linitis plastica. So the best description is that intestinal type forms gland-like structures, while diffuse type shows signet-ring cells with diffuse infiltration, explaining the distinct histologic patterns.

The main histologic distinction is gland formation. Intestinal-type gastric adenocarcinoma tends to organize into gland-like structures that resemble intestinal epithelium, with cohesive neoplastic cells forming tubules and glands. Diffuse-type, on the other hand, lacks these glands and infiltrates the stomach wall as individual, discohesive cells, often with signet-ring morphology where mucin pushes the nucleus to the cell's periphery. This diffuse infiltration can cause thickening and rigidity of the stomach known as linitis plastica. So the best description is that intestinal type forms gland-like structures, while diffuse type shows signet-ring cells with diffuse infiltration, explaining the distinct histologic patterns.