How common is a breast lump in HER2-positive breast cancer?

HER2-positive breast cancer is a breast cancer whose cells have more HER2 protein than expected. A lump may be felt during self-awareness, a clinical examination, or seen on breast imaging. It can be firm or soft, and it may or may not be tender. Its presence does not reveal the HER2 status or confirm cancer. Cysts, fibroadenoma, infection, hormonal changes, and other benign breast conditions can also cause a lump.

Clinicians combine the examination with diagnostic imaging and, when needed, a tissue sample. Laboratory testing of sampled cells helps identify tumour features such as HER2 status. The lump's size, position, mobility, and associated skin or nipple changes can guide the next step, but none of these features replaces assessment.

Arrange an appointment for a new, persistent, or changing lump, even if it is not painful. Note when you first noticed it, whether it changes with your menstrual cycle, and whether you have nipple discharge, skin dimpling, redness, or swelling. Avoid repeatedly pressing the area, which can make it sore and make changes harder to judge. Bring information about pregnancy, breastfeeding, prior breast problems, and medicines to the visit.

Seek prompt medical advice for a lump with new skin puckering, nipple inversion, bloody discharge, marked redness, warmth, rapid swelling, or an enlarged node in the armpit. Fever with a hot, painful breast can indicate infection and also needs timely assessment. Sudden severe symptoms, breathing trouble, or feeling faint require urgent medical help.

You could ask: Which examination or imaging test is appropriate? Does the finding need a biopsy? If cancer is diagnosed, how will the tissue test assess HER2 and other markers? What changes should prompt an earlier review? When and how will I receive the results?