Breast cysts are fluid-filled sacs inside the breast, which are usually not cancerous (benign). You can have one or many breast cysts and they can happen in one or both breasts. They’re often described as round or oval lumps with distinct edges. A breast cyst usually feels like a grape or a water-filled balloon, but sometimes a breast cyst feels firm.
Breast cysts don’t require treatment unless a cyst is large and painful or uncomfortable. In that case, draining the fluid from a breast cyst can ease symptoms.
Breast cysts are common in women before menopause, between ages 35 and 50. But they can be found in women of any age. They can also occur in postmenopausal women taking hormone therapy.
Breast cysts may be found in one or both breasts. Signs and symptoms of a breast cyst include:
- A smooth, easily movable round or oval lump with distinct edges (which typically, though not always, indicates it’s benign)
- Nipple discharge that may be clear, yellow, straw colored or dark brown
- Breast pain or tenderness in the area of the breast lump
- Increase in breast lump size and breast tenderness just before your period
- Decrease in breast lump size and resolution of other symptoms after your period
Having breast cysts doesn’t increase your risk of breast cancer. But having cysts may make it more difficult to find new breast lumps or other changes that might need evaluation by your doctor. Be familiar with how your breasts normally feel so that you’ll know when something changes.
Breast cancer is cancer that develops in breast cells. Typically, the cancer forms in either the lobules or the ducts of the breast. Lobules are the glands that produce milk, and ducts are the pathways that bring the milk from the glands to the nipple. Cancer can also occur in the fatty tissue or the fibrous connective tissue within your breast.
Each type of breast cancer can cause a variety of symptoms. Many of these symptoms are similar, but some can be different. Symptoms for the most common breast cancers include:
- a breast lump or tissue thickening that feels different than surrounding tissue and has developed recently
- breast pain
- red, pitted skin over your entire breast
- swelling in all or part of your breast
- a nipple discharge other than breast milk
- bloody discharge from your nipple
- peeling, scaling, or flaking of skin on your nipple or breast
- a sudden, unexplained change in the shape or size of your breast
- inverted nipple
- changes to the appearance of the skin on your breasts
- a lump or swelling under your arm
If you have any of these symptoms, it doesn’t necessarily mean you have breast cancer. For instance, pain in your breast or a breast lump can be caused by a benign cyst. Still, if you find a lump in your breast or have other symptoms, you should see your doctor for further examination and testing. Learn more about possible symptoms of breast cancer.