The stages of breast cancer

FASLODEX is approved only for hormone receptor-positive metastatic breast cancer in postmenopausal women whose breast cancer recurred or progressed following antiestrogen therapy (stage IV breast cancer).

A breast is made up of lobules, ducts, fatty tissue, blood vessels, lymph vessels, muscles, and nerves. The lobules are tiny sacs that make milk during breast feeding. There are about one million lobules in each breast. The ducts are tubes that carry the milk from the lobules to the nipple. The fatty tissue surrounds the lobules and ducts to provide support. Lymph vessels carry lymph to lymph nodes in the underarm, above the collarbone, and in the chest. There are also lymph nodes throughout the body.

Your doctor will look at a number of factors, including the size of the tumor, the role of lymph nodes, and how far the cancer has spread, to determine the stage of your breast cancer. There are early stages of breast cancer (0, I, II, and IIIA) and advanced stages (IIIB/C and IV).

Breast Cancer Stages

Early stages of breast cancer

Stage 0

Cancer cells are present in either the lining of a breast lobule or a duct, but they have not spread to the surrounding fatty tissue. This stage is also called ductal carcinoma in situ, or DCIS.

Stage I

Cancer has spread from the lobules or ducts to nearby tissue in the breast. At this stage and beyond, breast cancer is considered to be invasive. The tumor is 2 cm or less in diameter (approximately 1 inch or less); the cancer has not spread to the lymph nodes.

Stage II

In this stage, the tumor can range from 2 cm to less than 5 cm in diameter (approximately 1 to 2 inches); sometimes cancer may have spread to the lymph nodes.

Stage IIIA

In this stage, the tumor is 5 cm or greater in diameter (approximately 2 inches or greater); or the tumor may be of any size where cancer cells have grown extensively into the axillary (underarm) lymph nodes.

Advanced stages of breast cancer

Stage IIIB/C

Known as locally advanced cancer; tumor may be of any size but has spread into the skin of the breast or tissues of the chest wall.

Stage IV

Known as metastatic; cancer has spread from the breast to other parts of the body, such as the bones, liver, lungs, or brain.

Breast cancer recurrence — the return of cancer following primary (initial) treatment — can occur at the same site as the original tumor or somewhere else in the body.