Stages of Breast Cancer
The stages of breast cancer are used to refer to the extent, or progression, of the disease. Once a diagnosis of breast cancer has been made, it's important to determine the stage in order to plan treatment of the disease. The stages range from stage 0 to stage IV and recurrent cases of breast cancer.
After a breast cancer diagnosis has been made, tests are done to find out if cancer cells have spread within the breast or to other parts of the body. This process is called staging.
The information gathered from this process determines the stage of breast cancer. It is important to know the stage in order to plan breast cancer treatment.
The breast cancer stages include:
- Stage 0 (including lobular carcinoma in situ and ductal carcinoma in situ)
- Stage I
- Stage II (including IIA and IIB)
- Stage III (including IIIA, IIIB, and IIIC)
- Stage IV
There are two types of stage 0 breast cancer:
- Ductal carcinoma in situ (DCIS)
- Lobular carcinoma in situ (LCIS).
Ductal Carcinoma in Situ (DCIS)
This is a noninvasive, precancerous condition in which abnormal cells are found in the lining of a breast duct. The abnormal cells have not spread outside the duct to other tissues in the breast. In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive.
Lobular Carcinoma in Situ (LCIS)
This is a condition in which abnormal cells are found in the lobules of the breast. This type seldom becomes invasive cancer; however, having lobular carcinoma in situ in one breast increases the risk of developing breast cancer in either breast.
In stage I breast cancer:
- The tumor is 2 centimeters or smaller
- The tumor has not spread outside the breast.