DELAYED COMPLICATIONS IN COLO-RECTAL CARCINOMA TREATED BY COMBINATION RADIOTHERAPY AND 5-FLUOROURACIL EASTERN COOPERATIVE ONCOLOGY GROUP (ECOG) PILOT-STUDY

From June 1976 to Dec. 1977, 24 patients with residual, or recurrent, inoperable rectal carcinoma, were treated by a split-course irradiation and 5-FU. All patients received 60Co pelvic irradiation, with AP-PA opposed fields. The dose was delivered in 3 courses of 2000 rad in 2 weeks, with 2 weeks rest between each course. 5 Fluorouracil (5-FU)-(500 mg/m2), was administered I.V., on the first 3 days of each course of irradiation. The acute reaction was minimal, and was not predictive of the late serious complications which occurred in 7 24 (29%), of our patients, 2 10 with minimal, and 5 14 with bulky pelvic disease. The median follow-up was 12 months-(range 4-26 months). The onset of serious complications occurred about 8 months following treatment, and consisted of bowel stenosis, necrosis, fistula formation, and subcutaneous fibrosis. In 5 of 7 patients, predisposing factors accounted for such complications. We believe this to be the first report of such an observation of delayed complications in the absence of serious early reaction with combined chemoradiotherapy. The safety of multimodality therapy cannot be predicted by how well it is tolerated initially. © 1979.