[Endometrial adenocarcinoma treated with combined radiotherapy and surgery: 437 cases]

To identify prognostic factors and treatment toxicity in a series of operable endometrial adenocarcinomas.

Between November 1971 and October 1992, 437 patients (pts) with endometrial carcinoma, staged according to the 1988 FIGO staging system, underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy without (n = 140) or with (n = 297) pelvic lymph node dissection. The chronology of RT was not randomized and depended on the usual practices of the surgical teams. Group I: 79 pts received preoperative uterovaginal brachytherapy (mean total dose [MD]: 57 Gy). Group II: 358 pts received postoperative RT (196 pts received vaginal brachytherapy alone [MD: 50 Gy], 158 pts had external beam pelvis RT [EPRT] [MD: 46 Gy over 5 weeks] followed by vaginal brachytherapy [MD: 17 Gy], and 4 pts had EPRT alone [MD: 46 Gy over 5 weeks]). The mean follow-up was 128 months.

The 10-year disease-free survival rate was 86%. From 57 recurrences, 12 were isolated locoregionally. Multivariate analysis showed that independent factors decreasing the probability of disease-free survival were: histologic type (clear cell carcinoma, p = 0.038), largest histologic tumor diameter > 3 cm (p = 0.015), histologic grade (p = 0.008), myometrial invasion > 1/2 (p = 0.0055), and 1988 FIGO staging system (p = 9.10(-8)). In group II, the addition of EPRT did not seem to improve locoregional control. The postoperative complication rate was 7%. The independent factors increasing the risk of postoperative complications were FIGO stage (p = 0.02) and pelvic lymph node dissection (p = 0.011). The 10-year rate for grade 3 and 4 late radiation complications according to the LENT-SOMA scoring system was 3.1%. EPRT independently increased the 10-year rate for grade 3 and 4 late radiation complications (R.R.: 5.6, p = 0.0096).

EPRT increases the risk of late radiation complications. After surgical and histopathologic staging with pelvic lymph node dissection, in a subgroup of intermediate risk patients (stage IA grade 3, IB-C and II), postoperative vaginal brachytherapy alone is probably sufficient to obtain a good therapeutic index. Results for patients with stage III tumor are not satisfactory.