"...These are sometimes seen in the breast after radiation therapy for breast cancer or in the arm on the same side as a breast that has been irradiated or removed by mastectomy..."

"Although a mastectomy does drastically reduce the occurrence of breast cancer, even the most experienced breast surgeon cannot remove all breast tissue and therefore a small risk of developing breast cancer..."

"...Treatment & Prevention: Surgery is generally required; modified radical mastectomy is the most common operation..."