Snap Shot A 28-year-old female recently discovered a lump in her right breast. She has no family history of breast cancer, and her menstrual cycle began at 13 years of age. On exam you find a 1-cm movable mass in the right outer/upper quadrant. There is no skin dimpling. A mammogram is shown. Introduction Most common cause of benign breast masses in premenopausal women Caused by exaggerated response to hormones and fluctuations in mass size Not typically associated with progression to cancer Several histologic types login to view 13 more bullets Presentation Symptoms login to view 2 more bullets