Does breast cancer cause a new lump or swelling?

The change may be in the breast, upper chest, or armpit. Cysts, hormonal changes, inflammation, infection, and other benign conditions can also produce a lump or swelling.

A breast cancer lump may feel firm or unlike the surrounding tissue, while swelling may affect part or all of a breast. Cancer can also involve lymph nodes near the armpit or collarbone.

Pain does not reliably separate cancerous from non-cancerous changes. A clinical examination and suitable imaging provide more useful information, and an abnormal area may need a tissue sample for diagnosis.

Book a clinical assessment for any new, unexplained breast or armpit lump or swelling, even if it is not painful. Record where the change is, when you noticed it, and whether it varies or is growing.

Avoid repeatedly pressing the area, which can make tenderness harder to interpret. The clinician may examine the breasts and nearby lymph nodes and select ultrasound, mammography, or other tests according to your situation.

Seek prompt medical review if a lump persists, grows, feels fixed, or occurs with skin dimpling, nipple inversion, unusual nipple discharge, or swelling near the armpit or collarbone. Assessment is warranted regardless of how common a benign explanation may be.

Rapid swelling with a hot, red breast, fever, severe pain, or feeling acutely unwell needs urgent care because infection is another possible cause that may require treatment.

You might ask which test fits the location of the change, whether nearby lymph nodes need imaging, and whether a biopsy is recommended. Clarify when results should be available and who to contact if the swelling changes before follow-up.