A retrospective analysis was carried out on 811 patients with histologically proven invasive carcinoma of the uterine cervix treated with irradiation alone. A correlation was made of the doses of irradiation delivered to the pelvic organs with external beam and intracavitary insertions. Approximately 3% of the patients exhibited grade 2 gastrointestinal complications, and 2% developed grade 2 urinary complications; 5% of the patients developed grade 3 gastrointestinal complications, and 3% developed grade 3 urinary complications. Other types of complications, primarily grade 2, such as vaginal necrosis, pelvic abscess, thrombophlebitis, etc, were seen in approximately 5% of the patients. Thus, the total percentage of patients developing grade 2 complications was 10% and grade 3 complications, approximately 8%. About 25% of the patients who had complications showed more than one sequela. The most frequently observed grade 2 complications were proctitis, cystitis, vaginal stenosis, and partial small bowel obstruction which were treated with conservative management. Grade 3 complications required surgical treatment and consisted most frequently of ureteral stricture, vesicovaginal fistula, rectovaginal fistula, sigmoid stricture, small bowel obstruction, proctitis, and large rectal ulcers. The most significant factor affecting the appearance of complications was the total dose of irradiation delivered to the pelvic organs by the whole pelvis external irradiation and intracavitary insertions. With maximum total doses up to 8000 rad the incidence of grade 2 and 3 complications was less than 5%. However, with higher doses the incidence of complications increased to 10% to 15%. In patients receiving total doses of 6000 rad to the bladder or rectum, more complications were noted when only one intracavitary insertion was performed, as compared with two or three. Eighty percent of the rectosigmoid complications occurred within 30 months of initial therapy, in contrast to 48 months for the urinary complications. Patients who developed complications had survival rates comparable to those without complications. This underscores the need to rapidly institute treatment on patients who have severe injury after radiation therapy.(ABSTRACT TRUNCATED AT 400 WORDS)