When to worry about a breast lump with HER2-positive breast cancer

A new, changing, or persistent breast lump needs prompt review, especially during HER2-positive breast cancer care. Breast Lump is a very common presentation of HER2-Positive Breast Cancer, but a lump can also have non-cancerous causes. Do not wait for a routine appointment if the change is rapidly worsening or accompanied by severe symptoms.

A lump may reflect the known cancer, a change in treated tissue, swelling, infection, or another breast condition. Its feel alone cannot identify the cause. Your clinician may compare it with earlier examinations and imaging, then decide whether further imaging or a tissue sample is needed. Tell the team when you first noticed it, whether it is growing, and whether it is near a treatment or surgery site.

Contact your oncology or breast-care team promptly and describe the location, size change, tenderness, skin appearance, and any nipple discharge. Keep scheduled treatment and imaging visits unless your team tells you otherwise. Avoid repeatedly pressing the area, which can increase soreness. Bring a list of medicines and note fever, recent procedures, injections, or injury that could affect the breast.

Seek urgent medical advice for a rapidly enlarging lump, spreading redness or warmth, marked swelling, fever or chills, pus-like drainage, heavy bleeding, severe pain, sudden breathlessness, or feeling faint. These signs can indicate infection or another problem needing quick assessment; they do not establish the cause by themselves. If you are receiving treatment, use the emergency contact supplied by your cancer team.

Ask: Could this be related to the cancer or its treatment? Which examination or scan is appropriate? How soon should I report a change? What symptoms should make me call outside office hours? Should I continue my planned medicines while this is assessed?