[Endosonography in preoperative assessment of rectal tumors].

Together with digital examination and rectoscopy, the endorectal ultrasound is of great value in the preoperative diagnostics of rectal carcinoma. In 90% of these patients it is possible to determine the depth of infiltration preoperatively. At the same time assessment of lymph node involvement can be made with a sensitivity and specificity of 78%. Thus, endorectal ultrasound gives decisive criteria for the therapeutic plan. Furthermore, endorectal ultrasound represents a fitting instrument for the postoperative follow-up of patients with anterior resection of the rectum. Intramural as well as extrarectal sited recurrences of the tumor can be detected. Whether endosonography will have an influence on the prognosis of rectal carcinoma, remains to be seen.