Ovarian Irradiation and Prednisone Following Surgery and Radiotherapy for Carcinoma of the Breast

Abstract

Because some recurrent breast cancers regress following therapeutic castration, several clinical trials have been carried out to test the value of prophylactic ovarian ablation as part of primary treatment. In the Manchester Trial, [2] ovarian irradiation (450 rad in one fraction), in premenopausal patients with histologically negative and positive axillary nodes, delayed the appearance of distant metastases (P = 0.04) but did not significantly prolong survival (P = 0.07 at 10 years. In the Oslo Trial, [5] ovarian irradiation (1000 rad in six daily fractions), in premenopausal (histologically positive axillary nodes) and postmenopausal (histologically negative and positive axillary nodes) patients, delayed recurrence and also prolonged survival at 7 years but the differences were small. In the Trial of the National Surgical Adjuvant Breast Group, [6] oophorectomy did not result in a significant delay in recurrence nor prolongation in survival during 3–5 years of follow-up in premenopausal patients who had either histologically negative or positive axillary nodes. Because of the ambiguity resulting from these trials, the following study was begun in 1965 to test the hypothesis that prophylactic ovarian irradiation, with or without prednisone, could not only delay recurrence but also prolong survival.