Abstract
From 1970 to 1981, 50 patients had curative surgery for carcinoma of the cecum, ascending, or descending colon and were Stage ≥B2. In 15 cases, the lesion originated on the antimesenteric (posterolateral) bowel wall. Of seven cases (with minimum three-year follow-up) not receiving adjuvant postoperative regional irradiation, four recurred in the tumor bed/abdominal wall versus 0/3 irradiated patients. Similarly, the five-year survival was improved in the irradiated group (2/3) versus only 2/9 in the unirradiated group. Patients with transmural extension of right or left colon cancers originating on the anti mesenteric (posterolateral) bowel wall may have a high incidence of postoperative regional failure which may be decreased by adjuvant postoperative regional irradiation.