Adjuvant irradiation after mastectomy in women with one to three positive axillary nodes: then no; now yes.

The decision whether to offer women with one to three positive nodes postmastectomy radiation after adjuvant chemotherapy has been the subject of intense discussion since the publication of two major randomized prospective trials. Although radiotherapy after mastectomy was an established treatment for women with four or more positive axillary nodes, before these studies, existing data did not justify its use in patients with less extensive nodal involvement. Now with results from these studies showing improved survival after radiotherapy in all node-positive premenopausal and perimenopausal women, with perhaps its greatest benefit in women with one to three positive nodes, practice patterns are again shifting toward strong consideration of treatment in women with less tumor involvement. The arguments supporting this new treatment philosophy are presented.