Five-year survival rates of 47% and 43% were reported for patients with surgically confirmed isolated para-aortic lymph node metastases and for those with para-aortic and pelvic lymph node metastases, respectively, using postoperative extended-field radiation.
In one report, only one case of severe enteric morbidity occurred in 48 patients, a complication rate of 2% (295). In a GOG study, 37 of 48 patients with positive para-aortic nodes received postoperative para-aortic radiation, 36% of whom remained tumor free at 5 years (132). A comparison of patients with positive para-aortic nodes treated with megestrol acetate alone versus megestrol acetate and extended-field radiation showed that the survival rate in the patients receiving extended-field radiation was significantly better: 53% versus 12.5%, respectively (296). In another study of 18 patients with positive para-aortic nodes, 5-year survival rates were 67% for microscopic nodal disease and 17% for gross nodal disease (297).
Whole-abdomen radiation therapy is usually reserved for patients with stages III and IV endometrial cancer. It may be considered for patients who have serous or carcinosarcomas, which have a propensity for upper-abdominal recurrence (299–304). The recommended dose to the whole abdomen is 3,000 cGy in 20 daily fractions of 150 cGy, with kidney shielding at 1,500 to 2,000 cGy, along with an additional 1,500 cGy to the para-aortic lymph nodes and 2,000 cGy to the pelvis. Gastrointestinal side effects, including nausea, vomiting, and diarrhea, sometimes make it necessary to interrupt therapy, but it is rare for patients to discontinue treatment because of these symptoms. Hematologic toxicity can be expected to occur during whole-abdomen radiation, but it is usually mild. The incidence of late complications, mainly chronic diarrhea and small bowel obstruction, is low (5% to 10%).
In a series of 27 patients treated with surgical stage III endometrial cancer with whole-abdomen radiation, patients with spread to the adnexa, positive peritoneal cytology, or both had a 5year, relapse-free survival of 90%, whereas all patients with macroscopic disease beyond the adnexa had recurrence (298). Similar results were reported by others (300,301). Some advocated the use of adjuvant whole-abdomen radiotherapy for patients with high-risk stagesI and II endometrial carcinoma, including those with deep myometrial invasion, high-grade tumors, and serous histology, because of the high proportion of recurrences in the upper abdomen. A 5-year recurrence-free survival rate of 85% was reported (302,303). With whole-abdomen radiation in patients at increased risk for intra-abdominal metastatic disease, such as those with nonnodal extrauterine disease and serous histology, an actuarial 5-year relapse-free survival rate of 70% was reported, with no significant toxicity (304). Similarly, others noted a 3-year disease-free survival rate of 79% in patients with stages III and IV endometrial adenocarcinoma treated with whole-abdomen radiation (305). Other reports of using adjuvant postoperative whole-abdomen radiation in early-stage uterine serous carcinoma suggest a reduction in recurrence rates (304– 306). Most recurrences are in the upper abdomen in all of these patients, despite use of this type of radiotherapy. After the publication of GOG122, demonstrating the superiority of chemotherapy over whole-abdominal radiotherapy in advanced endometrial cancer, the utilization of whole-abdominal radiotherapy is not common (see section on “Chemotherapy”) (307).