In two decades there has been a sweeping metamorphosis of the antiquated conception of breast cancer as a solitary mass of questionable operability, accompanied by numerous axillary lymph nodes and probably distant metastasis. An undreamed-of recognizable preclinical stage of breast cancer has drastically changed attitudes and reactions in physicians and patients. These changes have paralleled the applications of clinical mammography. The smallest of premammography breast cancers are now advanced cancers. The average size of operable breast cancers at Emory University is now less than 1 cm in diameter, and ten-year cure rates with minimal cancers exceed 95%. The treatment of these minimal breast cancers, often in a two-stage surgical procedure with the patient participating in decisions, may include psychotherapy and reconstructive surgery. Pathologists have assumed new roles in coping with disturbing epithelial cellular changes in premalignant and borderline malignant breast lesions. Today predictive clinical signs and symptoms are associated with advanced cancer, with limited specific clinical changes relating to early breast cancer. Over one third of breast cancers are being discovered in women under 50 years of age, and mammography is the primary means of detecting these cancers.