[Recent advance of endoscopic ultrasonography for evaluating gastroenterologic early cancer]

Lutz et al. made the first report in which ultrasonographic probe could differentiate cystic tumor from solid one. After that, endoscopic ultrasonography (EUS) have advanced rapidly in engineering and clinical application. EUS is the most accurate diagnostic method presently available to determine the depth of gastrointestinal cancer invasion. We have proposed the pattern analysis for the differentiation between cancer invasion and ulcer fibrosis, because fibrosis and cancer invasion have of the same echo level. USP is more useful and easy than EUS in cases with small and flat lesion without ulcer, and EUS should perform in remaining lesions that look like early cancer with ulcer and advanced cancer. Clinically, it is believed that the invasion of early gallbladder cancer limited to the proper muscle, the early pancreas cancer is less than 1 cm. It is also practicable with EUS to detect the these cancer easily and diagnose the local stage of gall bladder and pancreas cancer. Now we are performing IDUS (ER-US, PT-US) and 3D-EUS, and believing that these technics will be used commonly in the near future.