[Rectosigmoid carcinoma--role of postoperative follow-up pelvic CT]

Pelvic CT scans of 102 patients who underwent resection of rectosigmoid carcinoma are reviewed. Sixty one patients had abdominoperineal resection and 41 had abdominal resection and colostomy. Recurrent tumors developed in 31 patients (30.4%). The interval between surgery and tumor relapse ranged from 3 months to 108 months (median, 14 months). CT findings indicative of tumor recurrence included an eccentric, round or irregular presacral soft-tissue mass, 2-20 cm (16), marked enhancement after i.v. contrast administration (15), invasion of surrounding muscle and/or bone (4), six patients had perineal recurrent tumor which was eccentrically located and irregular in shape. Fifteen patients developed recurrent tumor after abdominal resection and colostomy. There were anastomotic recurrence (15), pari-anastomotic mass (5), regional metastatic adenopathy (6), ranging from 0.3 to 1.2 cm. Routine follow-up CT scan after rectosigmoid carcinoma resection is useful in depicting early recurrence and survival could be improved after salvage operation. Appropriate scanning techniques including air inflation of the remaining rectum and colon, i.v. contrast administration for enhancement of tumor mass and blood vessels are emphasized for improving the quality of CT images in order to differentiate recurrence or postoperative change, adenopathy or blood vessels. Enhancement of tumor mass and blood vessels are emphasized for improving the quality of CT images in order to differentiate recurrence or postoperative change, adenopathy or blood vessels.