Date Updated: 03/01/2023


Definition

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

You might notice:

  • A distinct lump with clear-cut edges.
  • A firm or hard area within the breast.
  • A thicker, slightly raised area in the breast that's different from the tissue around it.

You also might see these changes along with a lump:

  • An area of skin that has changed in color or turned red or pink.
  • Dimpling of the skin.
  • Pitting of the skin, which may look like an orange peel in texture.
  • A change in the size of one breast that makes it larger than the other breast.
  • Nipple changes, such as a nipple that turns inward or releases fluid.
  • Lasting breast pain or tenderness, which is in one area or may go on after your period.

A breast lump can be a sign of breast cancer. That's why you should get it checked by your health care provider as soon as you can. It's even more important to get a breast lump checked after menopause. The upside is that most breast lumps are benign. That means they are not caused by cancer.

Causes

Breast lumps can be caused by:

  • Breast cancer
  • Breast cysts (which are fluid-filled sacs in breast tissue that are not cancer. The fluid in a cyst looks like water. An imaging test called ultrasound is used to find out if a breast lump is a cyst.)
  • Fibroadenoma (a solid, benign growth within the breast glands. It is a common type of breast lump.)
  • Fibrocystic breasts (which tend to feel lumpy or have a ropelike texture when checked by a health care provider.)
  • Intraductal papilloma (a benign growth in a milk duct.)
  • Lipoma (a slow-growing lump involving fatty breast tissue. It can feel doughy, and it is often harmless.)
  • Trauma to the breast from a bump, breast surgery or other reasons.

Breast lumps also can be caused by health problems that can happen during breastfeeding, such as:

  • Mastitis (an infection in breast tissue.)
  • A milk-filled cyst that's usually harmless.

When to see a doctor

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

  • The lump is new and feels firm or fixed.
  • The lump doesn't go away after 4 to 6 weeks. Or it has changed in size or in how it feels.
  • You notice skin changes on your breast such as crusting, dimpling, puckering, or a change in color, including red and pink.
  • Fluid comes out of the nipple. It might be bloody.
  • The nipple recently turned inward.
  • There is a new lump in the armpit, or a lump in the armpit seems to be getting bigger.

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