New diagnostic approaches for early detection of gastric cancer

Detection of gastric cancer in early stages is vitally important for ascertaining better prognosis and quality of life for the patients. Therefore, every endoscopist should be trained to master enough diagnostic skills to identify early gastric cancer that often shows minimal alteration from the surrounding mucosa, easily evading detection. For the first step, it is essential that endoscopists understand the normal gastric mucosa as well as the mucosal changes caused by chronic H. pylori infection, a high-risk condition for the development of gastric cancer. Once a suspicious lesion is identified, use of a dye-spraying method may be useful to clarify structural alteration caused by neoplastic changes and facilitate the biopsy sampling. Development of zoom (magnifying) endoscopy enabling 80x magnification with a one-touch switch from conventional endoscopic observation helps to identify the detailed surface structure as well as the vascular architecture of the mucosa without tissue biopsy. Combined with chromoendoscopy, this powerful endoscopic method can be used to identify small cancer foci or delineate the margin of early gastric cancer that can be treatable by mucosal dissection. Other new modalities using a variety of optical devices have been developed but the real value of their utility still remains to be proven in the actual clinical settings.