Fibrocystic change is a catch-all term for many non-cancerous processes that happen in the breasts. It used to be called fibrocystic disease, but because it is so common, and because it really represents something that happens normally in breast tissue, its name was changed.
When a doctor says a patient has fibrocystic change, what they probably mean is the breasts may be lumpy and tender during certain phases of the menstrual cycle. When a breast radiologist uses the term, it is usually because they see cysts or other structural signs of the condition. In reality, there is not a set definition that all doctors agree on.
Fibrocystic change happens when female hormones (estrogen and progesterone) act on sensitive breast tissue. The current thinking is that these hormones cause a small amount of fluid to accumulate in breast tissue right before the period starts. Estrogen and progesterone can also cause a mild overgrowth of some of the benign cells that line the milk ducts. Because the level of these hormones fluctuates during the menstrual cycle, feelings of lumpiness, thickening, discomfort, or pain will also fluctuate.
Some drugs accentuate the feelings or actual physical alterations from fibrocystic change. These include Aldactone, which can be prescribed as a diuretic or for the skin; certain depression or anxiety medications, like Zoloft, Celexa, and Prozac; and many heart medications. Usually, patients are on these medications for a good reason, and because fibrocystic change doesn’t cause cancer, it’s not a good idea to stop the medications if it’s suspected they are causing fibrocystic change.
Fibrocystic change is common. In our practice, we see patients with it daily as either a feeling of pain or a lump. It does not lead to cancer. It may present with an imaging finding that is indeterminate, however, and so to be sure it’s not cancer it could lead to a follow-up or biopsy recommendation.
A good way to determine if pain or a lump is potentially caused by fibrocystic change rather than a mass is to examine the breasts at the end of the menstrual cycle. If something feels odd, patients are asked to wait a month to go through another cycle and check if the lump is still there. If it is, the safest course of action is to be checked by a doctor, and possibly undergo a mammogram and ultrasound for further evaluation.