The incidence of heterotopic gastric mucosa located in the submucosa in resected stomach specimens has been reported to be 3.0 to 20.1%. Heterotopic gastric mucosa is thought to be a benign disease, which rarely becomes malignant. Heterotopic gastric mucosa exists in the gastric submucosa, and gastric cancer rarely occurs in heterotopic gastric mucosa. Since tumors are located in the normal submucosa, they appear as submucosal tumors during endoscopy, and are diagnosed through endoscopic biopsies with some difficulty. For such reasons, heterotopic gastric mucosa is mistaken as gastric submucosal tumor. Recently, two cases of early gastric cancer arising from heterotopic gastric mucosa in the gastric submucosa were treated. Both cases were diagnosed as submucosal tumors based on upper gastrointestinal endoscopy, endoscopic ultrasound, and computed tomography findings, and in both cases, laparoscopic wedge resections were performed, the surgical findings of which also suggested submucosal tumors. However, pathologic assessment of the surgical specimens led to the diagnosis of well-differentiated intramucosal adenocarcinoma arising from heterotopic gastric mucosa in the gastric submucosa.

Detecting and locating accurately structure damages at an early stage is essential to minimization of catastrophic disasters, prevention of fatalities and provision of cost‐effective maintenance. We herein report a facile approach to detect structure damages and to accurately identify their locations by using an electrically conductive epoxy/graphene nanocomposite film. A percolation threshold of electrical conductivity was observed at 0.58 vol% of graphene platelets (GnPs, ~3 nm in thickness and ~15 μm in length); electrical conductivity of 3.3 S/cm was obtained at 9.00 vol% of GnPs. The epoxy/GnP composite film containing 9.00 vol% of GnPs was employed as an array of electrically conductive paths in horizontal and vertical directions to detect and locate structure's damages. Thermal stability and temperature coefficient of the composite film were studied. Relative resistance change due to temperature effect was fitted into an exponential function, which showed strong correlation with the temperature change. This implies that an algorithm can be developed to compensate drift errors in resistance measurement due to temperature variation. With the help of Internet of Things, our self‐sensing epoxy/graphene nanocomposite films have great potential for smart aerospace structural health monitoring.

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