ANALYSIS OF FAILURES IN PATIENTS WITH CLINICAL STAGE-I ENDOMETRIAL CARCINOMA TREATED WITH ABDOMINAL-SURGERY AND POSTOPERATIVE EXTERNAL PELVIS IRRADIATION

Background - Postoperative external pelvic radiotherapy is often delivered to patients with high-risk early stage endometrial carcinoma. However the efficacy of such adjuvant treatment in improving prognosis is still controversial. Methods - One hundred and three patients with clinical stage I endometrial carcinoma underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, partial colpectomy and selective lymph node sampling. No further treatment was given to the 38 patients with surgical stage I, well (G1) or moderately (G2) differentiated tumors and no (MO) or superficial (Ml) myometrial invasion (G1-G2,MO-Ml category). Postoperative adjuvant external pelvic radiotherapy was given to the 22 patients with surgical stage I, GI-G2 tumors and intermediate (M2) myometrial invasion (G1-G2, M2 category), to the 17 patients with stage I, poorly differentiated (G3) tumors and/or deep (M3) myometrial invasion (G3 and/or M3 category), to the 12 patients with stage II tumor, and to the 14 patients with stage III tumor. Results - Recurrence rates were 6.5% for stage I, 8.-3% for stage II, and 42.9% for stage III endometrial carcinoma (p=0.001). Patients with stage III disease had a higher incidence of both vaginal/pelvic and distant failures than patients with stage I-II disease (21.4% vs 2.2%, p=0.02, and 35.7% vs 5.6% p=0.004, respectively). Among the 77 patients with surgical stage I disease, the recurrence rate was 2.6% for G1-G2, M0-M1 category, 0% for G1-G2, M2 category, and 23.5% for G3 and/or M3 category (p=0.008). In this latter category, vaginal-pelvic and distant failure rates were 5.9% and 17.6%, respectively. Conclusions - These data seemed to show that postoperative adjuvant external pelvic radiotherapy was of limited benefit for patients with high-risk stage I endometrial carcinoma.