The authors report a 7.9% incidence of late severe ileal complications after abdominal and/or pelvic external
radiation therapy in 188 consecutive patients. All treatments were performed using 25 MV photon beams, with AP-PA field technique, a daily dose of 1.8-2 Gy, 5 times a week. One hundred and two (54.3%) patients were given whole pelvic irradiation up to 45-55 Gy without a boost, 64 patients (34%) received boost doses on limited volumes up to 60-65 Gy. The analysis of factors which could be useful in predicting a high risk of severe ileal sequellae, has shown that the main factor was the past history of previous
laparotomy. Thus, the incidence of chronic
ileitis in patients who have never been laparotomized in the past and who were treated by
radiotherapy alone, was 2.2% (2/97); in contrast patients with previous abdominal surgery whatever its purpose, showed in 13/91 cases (14.3%) severe ileal complications (p less than 0.05). In addition, the risk of chronic
ileitis increases with the number of previous
laparotomies irrespective of delay or purpose: 10.1% after one
laparotomy, 22.2% after two and 50% after three or more
laparotomies. The influence of these data on the planning of abdominal and/or pelvic external irradiation is discussed.