The stages of Breast Cancer

As illustrated above.

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.