Whole abdominal radiotherapy in the adjuvant treatment of patients with stage III and IV endometrial cancer: a gynecologic oncology group study

Abstract

Objective: To evaluate toxicity, survival, and recurrence-free interval in women with loco-regionally advanced endometrial carcinoma treated with postoperative whole abdominal radiation therapy.

Methods: Whole abdominal irradiation with pelvic plus or minus para-aortic boost was initiated within 8 weeks of total abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic washings, and selective pelvic and para-aortic node sampling in eligible, consenting patients.

Results: Of 180 evaluable patients entered on the study with surgically staged III and IV endometrial carcinoma maximally debulked to less than 2 cm, 77 had typical endometrial adenocarcinoma and 103 had high-risk histology, either papillary serous or clear cell carcinoma. Patients with typical endometrial adenocarcinoma were significantly younger and had significantly fewer poorly differentiated cancers. Proportionally, there were twice as many non-Whites with high-risk histologies as non-Whites with typical endometrial adenocarcinoma. Forty-five percent of patients with typical endometrial adenocarcinomas had positive pelvic nodes compared to 51% of those with high-risk histologies. Both histologic groups had similar distribution for performance status, para-aortic node positivity, site and extent of disease, and International Federation of Gynecology and Obstetrics (FIGO) stage. The frequency of severe or life-threatening adverse effects among 174 patients evaluable for radiation toxicity included 12.6% with bone marrow depression, 15% GI, and 2.2% hepatic toxicity. The recurrence-free survival rates were 29% and 27% (at 3 years) for the typical endometrial adenocarcinoma and high-risk histologies, respectively. The survival rates were 31% and 35%, respectively. No patient with gross residual disease survived.

Conclusion: Whole abdominal irradiation in maximally resected advanced endometrial carcinoma has tolerable toxicity, and it is suggested that the outcome may be improved by this adjunctive treatment in patients with completely resected disease.