The role of radiotherapy in ovarian cancer.

This paper reviews the role of external-beam radiotherapy in patients with epithelial ovarian cancer and updates the results of The Princess Margaret Hospital clinical trials. Patients with well differentiated cancers in Stage I (5% of total), have a very high probability of being cured by operation alone and usually require no postoperative treatment. At the other end of the spectrum, patients in Stage IV and those in Stages II and III with large-sized residual tumor masses (45% of the total) are only rarely cured by irradiation, and therefore their primary postoperative treatment should be chemotherapy. Between these two extremes, when all macroscopic tumor has been excised, or when there are small residual deposits within the pelvis, irradiation of the whole abdomen, from above the diaphragm to below the obturator foramina, with no liver shielding, and with a boost-dose to the pelvis, is frequently curative. It is not clear at present whether some of these patients might be equally or better treated with combined chemotherapy. Further study is also required to establish whether radiation therapy has a role in consolidating responses obtained with chemotherapy in patients presenting with large residual tumor masses.