Hyperplastic Polyps and Gastroduodenal Pseudomelanosis

Figure 3

Panel of two images; Prussian blue stain (×600) with blue pigment deposition confirming the presence of iron within histiocytes (a). And Fontana Masson stain (×600) of the small intestine with brown-black pigment deposition consistent with melanin or melanin-like substance deposition in the macrophages (b).

(a)

(b)