| [ Summary ] |
The EUS findings in seven cases of colorectal villous tumor were described. The diagnosis of villous tumors is made by its macroscopic appearance, and its histology is heterogenous; by using EUS. Villous adenoma components were visualized as a band-like low echoic area and tubulovillous adenoma components as a relatively low echoic area. Since villous tumors are large in dimension, miniature ultrasonic probes were not suited for observation because of the attenuation of ultrasound; a 7.5MHz ultrasonic endoscope was considered to be appropriate. Furthermore, perpendicular cross-sectional images, throughout the entire lesion, were rarely obtained, since the area to be observed is so large. Invasive cancer was not included in the seven cases examined with EUS, so the diagnostic ability, concerning the depth of invasion, could not be commented on. However, the pattern of the submucosal layer in villous tumors is extremely complicated, and evaluation of submucosal invasion is considered to be difficult. Consequently, EUS is not suited for determining indications of endoscopic resection for villous tumors. |