Intracavitary irradiation of endometrial carcinoma stage I by a high dose-rate afterloading technique

Intracavitary irradiation was administered to 366 patients with endometrial carcinoma stage I by a high dose-rate afterloading method using 60Co sources (bulb technique). In 275 cases hysterectomy and bilateral salpingo-oophorectomy were performed 6 weeks later and in 91 cases dilation and curettage was used to verify tumor eradication. In 58% of the hysterectomy specimens no residual carcinoma was detected at the histopathologic evaluation. In the group treated with radiotherapy alone 74% showed no carcinoma remnants in the curettings 3 months after therapy. The effect of the fractionation dose was evaluated in relation to the outcome of the histopathologic examination. The proportion of specimens with no residual carcinoma increased from 27% for the 5 Gy per fraction group to 78% for the 10 Gy per fraction group. Recurrences were recorded in 13% in the hysterectomy group and in 29% in the group treated with radiotherapy alone. The 5-year corrected survival rate for the combination-treated group was 88% and for the group treated with radiotherapy alone 72%. If the dose per fraction is specified in the range of 5 to 8 Gy the high dose-rate afterloading technique seems safe with a tumor control rate and a frequency of radiation reactions comparable to the manual radium method.