| Theme |
How to Diagnose Gastric Diseases in Patients without Helicobacter pylori Infection |
| Title |
Gastric Cancer without the H. pylori Infection (Undifferentiated‒type) |
| Author |
Yorimasa Yamamoto |
Department of Gastroenterology, Showa University Fujigaoka Hospital |
| Author |
Yusuke Horiuchi |
Division of Gastroenterological Internal Medicine, Cancer Institute Hospital |
| Author |
Junko Fujisaki |
Division of Gastroenterological Internal Medicine, Cancer Institute Hospital |
| [ Summary ] |
Although gastric cancer without the Helicobacter pylori (H. pylori) infection has a relatively high frequency of undifferentiated cancer types, its cause has not been clarified. One cause is genetic abnormality, hereditary diffuse gastric cancer (HDGC9 showing E‒cadherin gene mutation has been reported. Regarding an undifferentiated‒type gastric cancer without H. pylori infection, the mean patient age is 53.4 years, and the ratio of male to female patients is nearly the same. There are many signet ring cell carcinomas showing discolored, flat, or depressed lesions around 10 mm in size in the middle or lower part of stomach. In magnifying endoscopy with narrow band imaging, lesions showing a corkscrew pattern are few, and many lesions show the wide intervening part. Using Ki67 labeling index, it is speculated that the lesion has low proliferative potential. The lesions are considered to be a good indication of endoscopic submucosal dissection. |