Small lump in the left breast: what to know

Breast tissue can feel lumpy because of normal glandular tissue, a cyst, fibroadenoma, inflammation or changes linked with the menstrual cycle. A lump may feel soft, firm, tender, mobile or fixed, but these features cannot confirm its cause. Breast cancer commonly presents as a new breast lump, although most breast lumps are not cancer. The location on the left side does not determine what the lump is.

A clinician may examine both breasts and the nearby underarm area, then choose imaging such as ultrasound or mammography based on your age, symptoms and examination. A biopsy may be recommended when imaging needs tissue confirmation.

Book an appointment for a new, persistent or unexplained lump. Note when you first felt it, whether it changes with your period, and any pain, discharge, skin change or recent injury. Do not repeatedly squeeze or massage the area, because this can irritate it and make changes harder to judge. Continue ordinary breast awareness, checking for changes in both breasts and the underarms without trying to reach a diagnosis at home.

Seek prompt medical assessment if the lump is new and hard, seems fixed, grows, or occurs with skin dimpling, nipple inversion, bloody discharge, an underarm lump, redness or swelling. Fever, marked warmth and rapidly worsening tenderness can point to infection and also need timely care. Seek urgent help for severe illness, spreading redness or difficulty breathing.

Ask what the examination suggests, which imaging is suitable, whether the lump may relate to your cycle, and when you should receive results. If a biopsy is proposed, ask what it involves and how the result will guide the next step.