Computed tomographic scanning in rectal carcinoma.

Computed tomographic (CT) scanning has been used to assess the extent of local spread in 85 patients with rectal carcinoma. In 37 patients with carcinoma of the rectum who were scanned before surgery, good correlation was found between the extent of local invasion, as assessed by scanning, and that demonstrated at operation by histological assessment. Scanning is not a reliable method for assessing regional lymph node involvement. Forty-eight patients presented with recurrent rectal carcinoma after previous rectal excision (30 patients after abdominoperineal and 18 patients after anterior resection). CT scanning was shown to be a valuable tool in establishing the diagnosis of recurrent tumour. Most of these patients have spread which precludes further curative surgery. CT may identify those patients who have a resectable recurrence, but is especially valuable in planning radiotherapy which may be used for palliation.