Breast lumps


A breast lump can result from a harmless condition. Or it could be cancer. Understand breast lump causes and when you need to see a doctor.


A breast lump is a growth of tissue that develops within your breast. Different types of breast lumps can vary in the way they look and feel.

You might notice:

  • A distinct lump with definite borders
  • A firm, hard area within your breast
  • A thickened, slightly more prominent area in your breast that's different from surrounding breast tissue
  • Other breast changes, such as redness, dimpling or pitting of the skin
  • One breast that's noticeably larger than the other
  • Nipple changes, such as a nipple that's pulled inward or spontaneous fluid discharge from your nipple
  • Persistent breast pain or tenderness, which might increase during your menstrual period

Sometimes, a breast lump is a sign of breast cancer. That's why you should seek prompt medical evaluation. Fortunately, however, most breast lumps result from noncancerous (benign) conditions.


Breast lumps can be caused by:

  • Breast cancer
  • Breast cysts (fluid-filled sacs in breast tissue that are usually benign)
  • Fibroadenoma (a solid, benign mass most common in young women)
  • Fibrocystic breasts (lumpy or rope-like breast tissue)
  • Galactocele (a milk-filled cyst that's usually harmless)
  • Injury or trauma to the breast
  • Intraductal papilloma (a benign, wartlike growth in a milk duct)
  • Lipoma (a slow-growing, doughy mass that's usually harmless)
  • Mastitis (an infection in breast tissue that most commonly affects women who are breast-feeding)

Make an appointment to have a breast lump evaluated, especially if:

  • The lump feels firm or fixed
  • The lump doesn't go away after four to six weeks
  • You notice skin changes on your breast, such as redness, crusting, dimpling or puckering
  • You have discharge, possibly bloody, from your nipple
  • Your nipple is turned inward and isn't normally positioned that way
  • You can feel a lump in your armpit and it seems to be getting bigger


Last Updated:

December 23rd, 2020

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