POSTOPERATIVE EXTERNAL IRRADIATION AND PROGNOSTIC PARAMETERS IN STAGE-I ENDOMETRIAL CARCINOMA - CLINICAL AND HISTOPATHOLOGIC STUDY OF 540 PATIENTS

Abstract

During 1968-1974, 540 patients with stage I adenocarcinoma of the corpus uteri entered a prospective clinical trial to evaluate the effect of postoperative external pelvic irradiation. After primary surgery all patients received intravaginal Ra irradiation; 6000 rad were delivered to the surface of the vaginal mucosa. At the time vaginal Ra was given, the following randomization was performed: Group A received no further treatment (controls); group B received additional high-voltage irradiation to the pelvic field with a dose of 4000 rad to the pelvic lymph nodes. During the follow-up period of 3-10 yr a significant reduction in vaginal and pelvic recurrences was found in group B as compared with group A (1.9 vs. 6.9%, P < 0.01). More patients in group B developed distant metastases than those in group A (9.9 vs. 5.4%). The 5-yr survival rate was not improved by external irradiation. Only patients with poorly differentiated tumors (grade 3), which infiltrate more than half the myometrial thickness, might benefit from additional external radiotherapy. In almost 20% of 151 consecutive patients, tumor cells were in endothelial lined spaces. Significantly more deaths and recurrences were among these patients compared to those without vessel invasion (26.7 vs. 9.1%, P < 0.01).