Stages of Breast Cancer

The purpose of the staging system is to help organize the different factors and some of the personality features of the cancer into categories, in order to:

* best understand your prognosis (the most likely outcome of the disease)
* guide treatment decisions, since clinical studies of breast cancer treatments that you and your doctor will consider are partly organized by the staging system, and
* provide a common way to describe the extent of breast cancer for doctors and nurses all over the world, so that results of your treatment can be compared and understood.

Tumor sizes:
3 spheres measuring 1 cm, 3cm, 5cm



Stage 0

This stage is used to describe non-invasive breast cancer. There is no evidence of cancer cells breaking out of the part of the breast in which it started, or of getting through to or invading neighboring normal tissue. LCIS and DCIS are examples of stage 0.
Stage I

This stage describes invasive breast cancer (cancer cells are breaking through to or invading neighboring normal tissue) in which

* The tumor measures up to two centimeters, AND
* No lymph nodes are involved.

Stage II

This stage describes invasive breast cancer in which:

* The tumor measures at least two centimeters, but not more than five centimeters, OR
* Cancer has spread to the lymph nodes under the arm on the same side as the breast cancer. Affected lymph nodes have not yet stuck to one another or to the surrounding tissues, a sign that the cancer has not yet advanced to stage III. (The tumor in the breast can be any size.)

Stage III

Stage III is divided into subcategories known as IIIA and IIIB.
Stage IIIA

Stage IIIA describes invasive breast cancer in which:

* the tumor measures larger than five centimeters, OR
* there is significant involvement of lymph nodes. The nodes clump together or stick to one another or surrounding tissue.

Stage IIIB

This stage describes invasive breast cancer in which a tumor of any size has spread to the breast skin, chest wall, or internal mammary lymph nodes (located beneath the breast right under the ribs, inside the middle of the chest).

Stage IIIB includes inflammatory breast cancer, a very uncommon but very serious, aggressive type of breast cancer. The most distinguishing feature of inflammatory breast cancer is redness involving part or all of the breast. The redness feels warm. You may see puffiness of the breast's skin that looks like the peel of a navel orange ("peau d'orange"), or even ridges, welts, or hives. And part or all of the breast may be enlarged and hard. A lump is present only half of the time. Inflammatory breast cancer is sometimes misdiagnosed as a simple infection.

Stage IV

This stage includes invasive breast cancer in which

* a tumor has spread beyond the breast, underarm, and internal mammary lymph nodes, and
* a tumor may have spread to the supraclavicular lymph nodes (nodes located at the base of the neck, above the collarbone), lungs, liver, bone, or brain.

"Metastatic at presentation" means that the breast cancer has spread beyond the breast and nearby lymph nodes, even though this is the first diagnosis of breast cancer. The reason for this is that the primary breast cancer was not found when it was only inside the breast. Metastatic cancer is considered stage IV.