Preoperative irradiation for carcinoma of the rectum and rectosigmoid colon: reportof a National Veterans Administration randomized study.

In 1964 the Veterans Administration Surgical Adjuvant Group (VASAG) initiated a large-scale, controlled, randomized protocol to study the role of low-dose preoperative irradiation (2000-2500 rads/10fractions/12 days) in patients with operable adenocarcinoma of the sigmoid colon and rectum. This report analyzes the data in 700 patients, all at 5-year risk. There appears to be a definate benefit to irradiated patients who undergo abdominoperineal resections, when compared with the controls. This advantage is reflected in improvement of 5-year survival, and reduction in lymph node invasion, local recurrence, and distant metastases. A second protocol has been initiated in 30 VA hospitals employing a higher dose (3150 rads) to extended portals (toL2) to male patients who require abdominoperineal resections.