Lobular carcinoma begins in the lobes or lobules (glands that make breast milk). The lobules are connected to the ducts, which carry breast milk to the nipple.
- Lobular carcinoma in situ (LCIS): This type of cancer begins in the lobules and does not typically spread through the wall of the lobules to the surrounding breast tissue or other parts of the body. While these abnormal cells seldom become invasive cancer, their presence indicates an increased risk of developing breast cancer later.
- Invasive lobular carcinoma (ILC): Cancer starts in the lobules, invades nearby tissue and can spread (metastasize) to distant parts of the body. This breast cancer type accounts for about 1 out of 10 invasive breast cancers.
When abnormal cells form in the lobules, or milk-producing glands, of the breast, it is called lobular carcinoma in situ, or LCIS. This uncommon condition is not a type of breast cancer. Rather, women with LCIS have a greater risk of developing invasive breast cancer in either breast. About 25 percent of women with LCIS will develop breast cancer at some point in their lifetime. This subsequent breast cancer may occur in either breast, and may appear in the lobules or in the ducts.
Lobular carcinoma treatment options
Because LCIS is not actually cancer, treatment may not be recommended. If you are diagnosed with lobular carcinoma, you may want to discuss more frequent breast cancer screening with your doctor. Increasing surveillance can help ensure that any subsequent breast cancer is detected in its earliest, most treatable stages.