Lobular carcinoma in situ, called LCIS, is the name for the abnormal growth of cells in the lobules of the breast. LCIS is more common in women who have not yet reached menopause. Carcinoma refers to any cancer that begins in the skin or other tissues that line or cover internal organs. The term “in situ” refers to the fact that the carcinoma, or cancer, has not spread beyond the site of origin.

The presence of LCIS means that there is a small increase in the risk of developing invasive breast cancer later in life. However, it’s important to know that most women with LCIS do not develop invasive breast cancer.

Each breast contains many tiny lobules where milk is produced before and after childbirth. With LCIS, changes are found in the cells lining the lobules. When diagnosed, LCIS is often found in both breasts.

Most women with LCIS will not need further surgical treatment after a biopsy is conducted.  However, some medications, such as tamoxifen, may be suggested along with close observation.