Question: What types of benign breast lumps are most often found?
Answer: Benign breast lumps are very common, especially if we include not just lumps but a mammographic abnormality. And it turns out that in the United States alone, about a million women have a breast biopsy with benign findings. Biopsies were done to find out, "Was there cancer there?," but it's benign. Sometimes that's called 'benign breast disease,' even though it's not a disease.
Most often we find cysts; and there's really no increased risk of a breast cancer with those. But in about 30 percent of women, we find some excess proliferation; the cells are dividing. We don't know why. And that, we know, is associated with an increased risk of a later breast cancer of about two-fold.
So, we need to be at least mindful of this; we don't have to institute any type of treatment for it, but we want to follow that woman and make sure she's getting regular mammograms. In a small proportion of women, we actually find atypical cells; they're still benign, but there are too many of them and they're starting to look abnormal -- like they're on a trajectory to cancer. There, we want to be sure screening is happening, and we also talk to that woman about various chemoprevention strategies -- tamoxifen, raloxifene, for example.