A Case of Gastric Cancer With Endoscopic Intact Gastric Mucosa.

A 79-year-old man with histologically proven adenocarcinoma cells in the cardia was referred to our hospital for the treatment of gastric cancer. A repeat endoscopy, however, showed intact gastric mucosa at the cardia but pathologically showed adenocarcinoma cells in a slightly depressed esophageal lesion adjacent to the stomach. The patient, therefore, underwent endoscopic submucosal dissection (ESD) both to the distal esophageal and presumed cardia lesions to avoid under-treatment. Both ESD specimens, however, had no cancer cells. After careful endoscopic follow-up for 20 months, positron emission tomography showed a maximal standardized uptake value of 5.9 g/mL in the cardia, leading to the re-confirmation of adenocarcinoma cells in the cardia. The patient, therefore, underwent proximal gastrectomy and lymph node dissection. Postoperative pathological study showed cuboidal atypical cells forming irregular lumens and spreading widely in the submucosa with almost normal gastric and esophageal mucosa. Due to the lack of distinct submucosal heterotopic gastric glands in the stomach, this pathological condition seemed to have been caused by both the submucosal wide spreading of cancer cells and the loss of mucosal malignant foci. In conclusion, to avoid under-treatment, endoscopists should take this type of extremely rare gastric cancer with endoscopic intact gastric mucosa into consideration for differential diagnosis.