What should you know about lump at bottom of breast?

The bottom of the breast includes breast tissue, the crease beneath the breast, skin, fat, and the chest wall. A blocked sweat gland, irritated skin, a cyst, a rib or muscle-related change, and normal breast tissue can all feel like a lump there. Friction, moisture, or an underwire can make a surface lump sore.

A breast lump is a common presentation of breast cancer, but the lower position does not establish a diagnosis. Some breast changes are easier to feel when standing or lying in different positions, which is why a hands-on assessment may be useful.

Arrange a medical review if the lump is new, remains present, or is changing. Note whether it is in the breast itself or the crease, whether it moves, and whether the skin is irritated. Keep the fold dry, choose comfortable clothing, and avoid squeezing, puncturing, or repeatedly rubbing the area.

Tell the clinician about recent injury, infection, pregnancy, breastfeeding, hormonal changes, and any discharge. They may examine the breast and skin separately and decide whether imaging or another test is needed. Do not assume that a lump is caused by clothing simply because it sits under the breast.

Seek prompt review for a firm, fixed, enlarging, or persistent lump, or for dimpling, nipple inversion, bloody discharge, or a new change in breast shape. Get urgent care for rapidly spreading redness, severe pain, pus, or fever, which can signal an infection needing treatment.

Ask whether the finding is in the skin, breast tissue, or chest wall, and whether you need imaging. Ask how to care for the breast fold while waiting, which changes should be reported quickly, and when the area should be reviewed again.