Villous adenomas of the rectum: the accuracy of clinical assessment.

To avoid an unnecessary radical operation, it is important for surgeons to identify a clinically benign villous tumor of the rectum, especially in the middle third area, where a transanal approach may not be feasible. If the high accuracy of this clinical impression can be achieved, alternative methods such as piecemeal snare excision, or electrocoagulation, or both are justified. To evaluate the diagnostic accuracy of a benign rectal villous tumor, 151 patients with totally excised rectal tumors were reviewed. All of these patients had soft and nonulcerated lesions and were judged to be benign. Induration and ulceration of the lesions signified malignancy and were excluded. One hundred and fourteen patients (76%) had benign villous adenomas, 23 patients (15%) had superficial carcinomas, and 14 patients (9%) had invasive carcinomas. Hence the accuracy of detecting a clinically benign villous tumor of the rectum was 91%. This is high enough to avoid a more radical procedure when the clinical impression is that of a benign villous tumor of the rectum.