Slide 4 
Note the complex pattern of the malignant gland. Whereas the benign gland is lined by a single layer of cells, the malignant gland is hypercellular. This results in the stratification of malignant cells with the formation of an irregular, thickened gland wall. Small, accessory glandular lumina form in the wall of the major gland to form the so-called "gland-within-gland" pattern. Also note the irregular size and shape ("pleomorphism") of the nuclei of the malignant cells and the increased mitoses.

Slide 5
The gastric mucosa adjacent to the carcinoma shows chronic inflammation, glandular atrophy and distortion, and intestinal metaplasia. These findings are typical for chronic atrophic gastritis and as you know, the atrophic forms of gastritis show an increased incidence of gastric cancer.

Slide 6
Shows the intestinal metaplasia of the gastric mucosa at higher power. Note that the foveolar epithelium of the gastric mucosa has been replaced by absorptive cells and mucin secreting goblet cells typical of the intestinal mucosa. There is also intense chronic inflammation of the lamina propria.