Lobular carcinoma in situ (LCIS) and breast cancer risk
When abnormal cells grow inside the lobules of the breast, but have not spread to nearby tissue or beyond, the condition is called lobular carcinoma in situ (LCIS) (learn more about the anatomy of the breast). The term "in situ" means "in place". With LCIS, the abnormal cells are still "in place" inside the lobules. It is rare for LCIS to become breast cancer. However, LCIS increases the risk of breast cancer. Compared to women without LCIS, those with LCIS are seven to 12 times more likely to develop cancer in either breast [34]. Women with LCIS can develop invasive lobular cancer or invasive ductal cancer [35].
Find out more on different tumor types.
LCIS and breast cancer screening
Women with LCIS should see their health care provider for a physical exam every six to twelve months and get a mammogram every year [36]. This medical care helps ensure that if cancer does develop, it is caught early when it is most treatable.
Risk-lowering options for women with LCIS
Women with LCIS may consider taking tamoxifen or raloxifene to prevent the development of invasive breast cancer [36]. Studies show that in both pre- and postmenopausal women with LCIS, tamoxifen reduces the risk of invasive and non-invasive breast cancer [37,38]. Raloxifene is as effective as tamoxifen in reducing the risk of invasive breast cancer [39,40]. However, raloxifene is only for use among postmenopausal women. Learn more about these risk-lowering drugs. For a summary of studies on tamoxifen and raloxifene, visit the Breast Cancer Research section.
A more drastic option for lowering the risk of breast cancer is to have a prophylactic bilateral mastectomy. This surgery involves removing both breasts to try and keep cancer from developing. Because regular breast cancer screening and tamoxifen (or raloxifene) are effective in greatly reducing risk, most women with LCIS choose this option over prophylactic bilateral mastectomy.
Learn more about options for women at higher risk.
Find questions about LCIS for your health care provider.
Find out more on talking to your health care provider.
Updated 11/09/09
