Figure 4.

a. PAS-positive mucous cells (pink, star), and brown chromogranin A-positive endocrine cells (arrow) in the normal appendiceal mucosa, b. PAS-positive mucin-secreting cells (pink, star), surrounded by brown chromogranin A-positive endocrine cells (arrow) in a tumour gland in the submucosa, c. Alciane blue-positive mucous cells (blue, star) and brown chromogranin A-positive endocrine cells (arrow) in the normal appendiceal mucosa, d. Alciane blue-positive mucin-secreting cells (blue, star), and brown chromogranin A-positive endocrine cells (arrow) in a tumour gland. (A combined histochemical and immunohistochemical staining). Magnifications a, b, c d × 300.