Diffuse submucosal cysts of the stomach associated with gastric cancer: contribution of Helicobacter pylori infections

Diffuse submucosal cysts (DSCs) in the stomach are often associated with gastric cancer and a high occurrence of multiple gastric cancers. We studied the clinicopathological features of four early gastric cancer patients with DSCs in the submucosal layer of the stomach. All patients had early gastric cancers with gastritis and erosion in the gastric mucosa, and were positive for Helicobacter pylori (H. pylori). Based on a review of the reported cases, we found that a very high proportion (>94%) of DSCs are associated with infection by H. pylori. Although DSCs have previously been considered to be paracancerous lesions of gastric cancer, we speculate that DSCs might be post-inflammatory changes following infection by H. pylori, which may result in the high incidence of gastric cancer development.