[Diagnosis of the infiltrating depth of the colonic cancer by endoscopic ultrasonography (EUS)].

Endoscopic ultrasonography (EUS) is the latest procedure in the field of gastroenterology and is highly evaulating now because of its unique diagnosing method. For the example, the intra- and extra-mural informations of the GI tract can be known through this technique. In this paper, we reported on the usefulness of EUS in the diagnosis of the depth invasion of the colonic cancer and introduced the new and exclusive instrument for the colon. Namely, we could obtain the accurate diagnosis in 18 out of 20 cases with the rectal or the sigmoid colon cancer. One of causes of misdiagnosis in 2 cases of early cancer was due to the ghost echo. Another cause was the cancer cells infiltration to the deeper tissue which could be recognized only by a microscope. Then, we tried to examine the entire colon in 2 cases using the new instrument and succeeded to insert the endoscope to the cecum in a short time. In conclusion, we were convinced that EUS would develop the new aspect in the diagnosis of the colonic diseases including cancer.