There has been a considerable amount of data presented to implicate moderate to severe fibrocystic disease as a strong precursor of breast cancer. When a premenopausal woman with nodular breasts presents a biopsy examination characterized by sclerosing adenosis, intraductal hyperplasia and/or papillomatosis, microcystic disease, macrocystic disease, or lobular neoplasia, her malignant potential will be much greater than when these disease processes are absent. As a result, a prophylactic subcutaneous mastectomy is indicated and breast reconstruction with either an immediate or a delayed mammary prosthesis implantation should be performed.