Background: Fundic gland polyps (FGPs) are common hamartomatous cystic lesions in the gastric mucosa. The aim was to assess the cellular components in sections stained with Giemsa or toluidine blue: two stains that easily differentiate parietal from chief cells.
Materials and methods: Sixty-eight consecutive gastric biopsies having well-oriented sections from the fundic mucosa were investigated: 34 had FGP, and 34 were control cases. Using an ocular microscale, the thickness of each FGP was divided into an upper and a lower compartment. The proportion of parietal and chief cells in each compartment was assessed in 3 consecutive high power fields (×40).
Results: In FGPs, parietal cells predominated in the upper compartment where the parietal chief cell ratio ≥60 was 59.8%, and in the lower compartment it was only 5.9% (p<0.05). Within cysts, cell exfoliation with secondary eosinophilic nuclear-free material was found. FGPs also displayed small glandular islands with an admixture of parietal and chief cells. The cytoplasm of parietal cells was often ballooned, vacuolated, with basophilic deposits or anucleated (ghost cells).
Conclusion: FGPs are composed of parietal cells predominantly in the upper half and with chief cells in the lower half, as well as with glandular islands showing cytological alterations in parietal cells. Intraluminal nuclear-free material seems to obstruct the outlets of the glands leading to cystic formation.