What can a lump in breast mean besides cancer?

Cysts, benign tumors: In my surgical practice, the most common cause of a well-defined breast lump is a cyst. This can easily be differentiated from a tumor by ultrasound or needle aspiration. If the lump is solid, it may be due to a benign tumor (ie, fibroadenoma) or a cancer; the only way to determine this is by tissue diagnosis, which can usually be done by needle-biopsy in the office or breast center.

Many things: Cysts are common. Other things include breast papillomas, fat necrosis, sometomes skin conditions that overlie the breast. Many lumps are simply normal breast tissue that is denser in some areas than others (we used to call this fibrocystic disease). We use mammography and ultrasound to aid our diagnostic capabilities.

Many things: Could be a benign cyst, an infection, a benign tumor such as a fibroadenoma.

Multiple things : It could be an abscess, cyst, fibroadenoma, lipoma, hematoma... See your doctor to evaluate the mass.