Observation of gastric glandular cysts in the corpus mucosa of the stomach under omeprazole treatment.

In patients undergoing long-term treatment with omeprazole, tiny gastric polyps, described histologically as glandular cysts, have occasionally been reported. We report on a further nine patients (5 women and 4 men) undergoing omeprazole treatment who developed endoscopically visible and histologically verified glandular cysts. Eight patients were on long-term treatment with omeprazole for reflux oesophagitis, and the glandular cysts were observed between 8 and 60 months after the start of treatment. In one patient with an NSAID-induced ulcer, a tiny polyp was found only three weeks after initiation of treatment. None of the patients had Helicobacter pylori-associated gastritis. The cysts, which measured between 0.25 and 0.7 mm in diameter, were mostly lined with flattened parietal and chief cells, but in three cases also with foveolar epithelium, so that they could not be reliably distinguished from Elster's gastric glandular cysts. These glandular cysts are harmless, and do not require further diagnostic or therapeutic measures. They probably develop spontaneously independently of the omeprazole therapy.