Tamoxifen and gynecomastia: before and after

Gynecomastia is enlargement of glandular breast tissue, often felt as a firm or tender area beneath the nipple. Tamoxifen changes how oestrogen signals are handled in different tissues, but a breast change can have several causes. It may be related to the medicine, another hormone imbalance, or a separate breast condition. A clinician may compare both sides, review medicines and health history, and decide whether examination or imaging is needed. A photograph or self-measurement cannot establish the cause.

Tell the prescribing team about breast swelling, pain, nipple discharge, a change in shape, or a lump. Do not stop tamoxifen or start a supplement on your own; the right choice depends on why it was prescribed and your cancer plan. Keep a simple record of when the change began and whether it is one-sided, tender, or increasing. After a treatment change, attend the planned review so the team can assess symptoms and discuss options if they persist.

Arrange prompt medical review for a new or growing lump, persistent one-sided enlargement, skin dimpling, nipple inversion, or bloody discharge. Seek urgent help for sudden chest pain, breathlessness, coughing blood, or one-sided leg swelling, because these symptoms can signal a clot or another emergency. Breast enlargement alone does not identify cancer; examination is what clarifies the concern.

Could this be glandular tissue, fluid, fat, or another breast change? Do I need an examination or imaging? Should my tamoxifen plan change? Which symptoms should I report immediately?