ADJUVANT WHOLE ABDOMINOPELVIC IRRADIATION FOR HIGH-RISK ENDOMETRIAL CARCINOMA

Fifty-six patients with surgical Stage III or IV endometrial carcinoma, or earlier stage disease with two or more risk factors for peritoneal recurrence, were given postoperative whole abdomino-pelvic irradiation (WAPI) with nodal and vaginal boosts between November 1981 and May 1989. Mean age at diagnosis was 63 years. Twenty-seven patients were surgical Stage I-II, 17 Stage III, and 12 Stage IV. Thirty-seven (66%) had deep myometrial involvement, 34 (61%) had positive peritoneal cytology, 31 (55%) had high grade lesions, 20 (36%) had either serous-papillary or adenosquamous histologic variants, and 13 (23%) had up to 2 cm residual disease remaining after surgery. Mean overall follow-up was 45 months. The 7-year actuarial survival was 63.8% with a 7-year disease-free survival (DFS) of 60.9%. By surgical stage, the 7-year DFS was 77.1% for Stage I-II, 57.8% for Stage III, and 25.0% for Stage IV (p = 0.006). The 7-year DSF was 79.8% for those with lesions of Broder's grade 1 or 2, and 46.9% for grades 3 or 4 (p = 0.001). Multivariate analysis demonstrated that of all covariates considered, only surgical stage and histologic grade had prognostic significance for survival and disease-free survival. Acute toxicity has been common but mild; chronic toxicity has been almost entirely subclinical with the exception of three cases of moderate to severe bowel toxicity. These results suggest that postoperative WAPI is a safe and efficacious treatment alternative for patients with surgical Stage I through III high-risk endometrial carcinoma.