What is a breast cyst?

A breast cyst is a benign (non-cancerous) fluid-filled sac in the breast. They are most common in pre-menopausal women and in post-menopausal women taking hormone therapy. Some cysts are too small to feel and others may be quite large and uncomfortable. Sometimes there are clusters of cysts in one breast or both.

What causes breast cysts?

Cysts are felt to be influenced by hormonal changes. Cysts form when fluid accumulates in the breast glands and connective tissue.

What are the symptoms of a breast cyst?

A breast cyst is typically a smooth lump with defined edges. Sometimes they are painful in the days prior to your menstrual cycle or in response to high caffeine intake. They are rarely associated with cancer. It is important to know that not all smooth lumps are breast cysts, and if you have a lump you should be checked by your breast provider.

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