Pre-operative versus postoperative irradiation in stage I carcinoma of the endometrium.

A retrospective analysis of 180 cases with clinical stage I endometrial carcinoma was done in an attempt to determine the role of pre- versus postoperative irradiation (RT). One hundred and forty-eight patients were treated pre-operatively and 32 patients received postoperative irradiation. The incidence of middle and outer 1/3 myometrial invasion was 7% and 4% in the pre-operative RT versus 28% and 31% in the postoperative RT group, respectively. Three percent of the pre-operative RT group and 28% of the post-operative RT patients were found to have a higher pathological stage at the time of hysterectomy. The overall five year actuarial survival rate in the pre- and postoperative irradiation groups was 88% and 75% (p = 0.128) respectively. The 10 year survival in the pre-operative RT group was 84% versus 51% (p = 0.056) in the postoperative RT patients. There was a significant improvement (p = 0.006) in ten year actuarial survival of patients with hysterectomy specimen free of malignancy (97%) as compared to (70%) survival of patients with residual diseases. The overall failure rate was lower (9%) in the pre-operative RT as compared to 28% in the postoperative RT group (p = 0.02) with pelvic recurrences of 2% and 13%, respectively (p = 0.01). The major complication rate was 3% in the pre-operative RT versus none in the postoperative RT group. The rate of complications correlated with the dose and technique of irradiation. Our results suggest that pre-operative irradiation decreases the depth of myometrial invasion and the rate of pelvic recurrences, lowers the pathological stage and probably increases the survival compared with postoperative irradiation.