Toxicity of open-field whole abdominal irradiation as primary postoperative treatment in gynecologic malignancy.

Abstract

Between June 1979 and March 1985, 77 patients received whole abdominal radiation as the sole postoperative treatment for gynecologic malignancy. With an open-field technique of irradiation, a median of 3,000 cGy was delivered to the entire abdominal contents with partial liver and kidney shielding; the total dose to the pelvis after boosts was 5,100 cGy, and that to the sub-diaphragmatic and para-aortic nodal regions was 4,200 cGy. The primary sites of malignancy were the endometrium in 41 patients, ovary in 25, uterus in 5, fallopian tube in 4, and cervix in 2. Seven patients (9%), all older than 60 years, experienced acute gastrointestinal toxicity that interrupted treatment, only one of whom failed to complete the prescribed course as a result. Hematologic toxicity was sufficient to interrupt therapy in 21 patients (27%), 1 of whom failed to complete therapy as a result. Hematologic toxicity was not increased in elderly patients. All patients were followed up for a minimum of 30 months (median, 43 months) or until death. Six patients experienced a treatment-related bowel obstruction (two of whom had concomitant progressive intra-abdominal disease); the 3-year actuarial risk for a treatment-related bowel obstruction was 9%. This risk was significantly increased by high-dose boosting for residual disease. Only one instance of clinical radiation pneumonitis occurred, and no cases of clinical hepatitis were noted; however, subclinical evidence of pulmonary and hepatic radiation effect was frequent. Whole abdominal irradiation as described has modest toxicity for patients with gynecologic cancer who are at high risk for intra-abdominal failure.