Breast cysts

What are breast cysts?

Breasts are made up of lobules (milk-producing glands) and ducts (tubes that carry milk to the nipple), which are surrounded by glandular, fibrous and fatty tissue. Sometimes, fluid-filled sacs develop in the breast tissue; these are breast cysts

Breast cysts are a benign  condition (not cancer). They are common and harmless. It is thought that they develop naturally as the breast changes with age in response to normal changes in hormone levels.

Although breast cysts can occur at any age, they are most common in women over 40 who haven’t yet reached the menopause. They occur more frequently as women get closer to the menopause and usually stop, or are not as frequent, afterwards. However, women who are taking hormone replacement therapy (HRT) after the menopause may also develop cysts.

Cysts can feel soft if they’re near the surface of the skin or like a hard lump if they’re deeper in the breast tissue. They can develop anywhere in the breast but are more often found in the upper half. For some people cysts can feel uncomfortable and even painful.

Before a period cysts may become larger and feel sore and tender. Sometimes people can have a cyst and not be able to feel it at all.

It’s quite common to develop one or more cysts – either in one breast or both breasts – and this is nothing to worry about.

How are they found?

Cysts usually become noticeable as a lump in the breast, or are sometimes found by chance when you have a breast examination or routine breast screening mammogram (breast x-ray).

Your GP (local doctor) may say whether the lump feels like a cyst, but they are likely to refer you to a breast clinic where tests will give more information.

At the breast clinic you will have a breast examination. You may also have a mammogram (breast x-ray) or ultrasound scan.

Ultrasounds are useful for women under 40 whose breast tissue is often too dense for a clear mammogram image. If the lump can be felt easily your specialist may put a fine needle into it to confirm that it is a fluid-filled cyst and to draw off the fluid.

Treatment and follow up

If you have a breast cyst or cysts you won’t usually need any further treatment or follow up. Many cysts go away by themselves and are nothing to worry about.

If the cyst is large and causing discomfort, or doesn’t go away on its own, your specialist will draw off the fluid using a fine needle and syringe. Once the fluid has been drawn off the cyst usually disappears.

Fluid from the cyst can vary in appearance from clear to very dark. It’s usually only sent to a laboratory for testing if the lump doesn’t disappear completely – as it may be a sign of another benign breast condition – or if it’s bloodstained, as there’s a very small risk that this may be a sign of breast cancer.

It is normal for cysts to come back, refill or for you to develop new ones. If this happens, visit your GP to have it checked as the fluid may need to be drawn off again.

 

Last reviewed March 2012; next planned review 2013