Four hundred ninety-seven cases of Stage I, Group I endometrial adenocarcinoma were treated by surgery alone (50 cases) or combined surgery and irradiation (447 cases). Radiation modalities used were uterine radium (327 cases), vaginal radium (30 cases), external pelvic irradiation plus radium (40 cases), and external pelvic irradiation alone (50 cases). T h e results of these different approaches were evaluated from the point of view of 5-year cure rates, relative morbidity, and incidence of recurrence. Clinical evidence of increased cure rate was seen in those receiving adjuvant irradiation, although the difference was not statistically significant. T h e most favorable results followed adjuvant uterine radium and adjuvant external pelvic irradiation plus radium. T h e difference in uterine depth did not influence the results. T h e degree of differentiation of tumor and myometrial invasion was of prognostic significance. Adjuvant irradiation improved the results in less differentiated tumor.
T h e presence of residual tumor in the removed uteri after irradiation had little influence on the prognosis. The combined effects of surgery and irradiation were well tolerated with a low morbidity rate. A decrease in the incidence of recurrence followed the use of all forms of irradiation.
COMBINATION OF SURGERY AND IRRADIA-
A tion has long been used for the treatment of clinically operable adenocarcinoma confined to the corpus uteri.3-4 . 7 , However, in some recent studies,lp 2 the role of adjuvant radiotherapy in improving the surgical results has been disputed.
Adjuvant radium, external irradiation, or combined radium and external irradiation have been used at Roswell Park Memorial Institute in a relatively large number of primary Stage I, Group I endometrial adenocarcinoma patients, preceding or following hysterectomy. T h e aim of this study is to determine the effectiveness of adjunctive radiotherapeutic procedures with reference to