The operation of radical mastectomy is widely, and in my opinion, properly employed in the management of patients with stage II cancer of the breast. If the axillary nodes are found to be negative on microscopic examination, and if the primary tumor is small and confined to the outer aspect of the breast, the most common site, then radiotherapy is not indicated. If, however, the primary tumor is situated in the inner aspect of the breast or centrally or if the tumor is large or the axillary nodes are found by the pathologist to contain metastases, then the question immediately arises as to whether the tumor has already spread beyond the limits of the operation. If such is the case then it would seem logical to supplement surgery by some form of treatment which has a chance of being curative. Undoubtedly the most important therapeutic measure in moderately advanced carcinoma