What is Invasive Lobular Carcinoma?

Invasive lobular carcinoma (ILC) is a type of breast cancer. ILC starts within the milk glands (lobules) of the breasts. As its name implies, ILC spreads to, or "invades" other breast tissue.

Statistics for ILC

According to the American Cancer Society, ILC accounts for about 10% of new invasive breast cancer cases.

Symptoms of ILC

A mammogram may show abnormalities in the breast tissue, but ILC rarely forms a hard tumor. That’s because as it spreads, it causes a thickening or hardening of the connective tissue within the breast.

Some women may have symptoms of ILC including:

  • Changes in the breast shape
  • Breast or nipple pain
  • Discharge from the nipple
  • Swelling of the breast
  • A lump
  • Thickening of the nipple skin

Other Names for ILC

Invasive breast cancer, lobular carcinoma, infiltrating lobular carcinoma, lobular breast cancer

Types of ILC

By looking at the cancer cells and tissue samples under a microscope, pathologists can see how cancer cells are growing and forming.

If the cancer cells are uniform and straight and attaching themselves to the fatty tissue and ligaments in the breast, it is called classic ILC.