Intrarectal sonography. A new technique for the assessment of rectal tumors.

Preoperative staging of rectal tumors provides a selective therapeutic approach. Twenty-three patients were evaluated with prospective intrarectal sonography. Endosonography identified all 21 rectal lesions. Two patients with previous rectal carcinoma had no evidence of recurrence. Thirteen of 17 patients (76%) with rectal carcinoma were correctly staged by endosonography. A submucosal leiomyosarcoma and pararectal arachnoid cyst were correctly identified. Preoperative assessment of lymph node status was accurate in five of ten patients (50%). Results of preoperative digital rectal examination predicting rectal wall involvement correlated with pathologic findings in 11 of 15 patients (73%). Intrarectal sonography is an important staging technique for preoperative evaluation of rectal wall invasion and guides appropriate surgical intervention.