A 37-year-old woman G2P2 presents with a lump in her left breast. Her husband noticed it recently and she is concerned, especially as she had an aunt that had breast cancer and thinks that a great-grandmother or some other ancestor may have died of breast cancer as well. Both of her children (9 and 7) were delivered without complication and she breastfed “for well over a year” with each. She has no other significant PMH or allergies. She is 5’ 6” tall, weighs 144 pounds and has a BMI of 22 and works as an office manager. She is a non-smoker, considers herself to be an “almost” vegetarian and has a glass of wine many evenings with dinner. She has regular physicals and is up to date on pap smears which have always been normal. Meds include a daily multi-vitamin and occasional acetaminophen for tension headache or ibuprofen during her period. Upon examination, the lump is discovered. It is firm and near the surface and no other masses are discovered. The lump is aspirated, and an opaque liquid is removed. Following this procedure, the lump has vanished. What is the differential diagnosis? What would be any further screening or treatment options? What is her risk of developing breast cancer?