breast cancer stages | Stages of breast cancer

Stages of breast cancer

The staging describes or classifies cancer according to the amount of cancer present in the body and its location during the initial diagnosis. This is often referred to as the extent of cancer. The information revealed by the tests is used to determine the size of the tumor, what part of the breast is affected by cancer, whether the cancer has spread from its place of origin and where it has spread. Your healthcare team uses the stage to plan your treatment and anticipate the outcome (your prognosis).

The most commonly used staging system for breast cancer is the TNM classification. In the case of breast cancer, there are 5 stages, the stage 0 followed by stages 1 to 4. For stages 1 to 4, Roman numerals I, II, III and IV are often used. But in order to make the text clearer, we will use Arabic numerals 1, 2, 3 and 4. In general, the higher the number of the stage, the more the cancer has spread. Talk to your doctor if you have any questions about the staging.

When doctors describe the stage of breast cancer, they sometimes classify it in the following categories:

In situ breast cancer – cancer cells are found only in the canal or lobule in which they originated and did not invade the nearby breast tissue (non-infiltrating tumor). It's stage 0 cancer.

Early breast cancer – the tumor measures less than 5 cm and the cancer has not spread to more than 3 lymph nodes. It's a stage 1a, 1b or 2a cancer.

Locally advanced breast Cancer – the tumor measures more than 5 cm. The cancer may have spread to the skin, to the muscles of the chest wall or to more than 3 lymph nodes. It is stage 2b, 3a, 3b or 3c cancer. Inflammatory breast cancer is also considered to be a locally advanced cancer.

Metastatic breast cancer – cancer has spread to other parts of the body. It's stage four cancer.

Learn more about the staging of cancer.

There are several groups of lymph nodes around each breast. The stage often depends on the lymph nodes in which the cancer has spread.

Diagram of the lymph nodes of the breast

Stage 0 (carcinoma in situ)

One of the following statements applies:

Cancer cells are only found in the lining of a breast canal. It is ductal carcinoma in situ (DCIS).

There is an accumulation of abnormal cells in the lobules of the breast. It is a lobular carcinoma in situ (CLIS).

Paget disease is observed without invasive carcinoma, DCIS or CLIS.

Stage 1a

The tumor measures 2 centimeters or less.

Stadium 1b

The tumor measures 2 cm or less or no tumors are detected in the breast. A small number of cancerous cells are observed in the lymph nodes (microstasis). Each ganglion reached by cancer does not measure more than 2 mm.

Stage 2a

The tumor measures 2 cm or less or no tumors are detected in the breast. Cancer cells are observed in 1 to 3 armpit lymph nodes (axillary lymph nodes), in lymph nodes located inside the thorax, around the sternum (internal mammary glands) or in these two regions.

Yes

The tumor measures more than 2 cm but not more than 5 cm.

Stage 2b

The tumor measures more than 2 cm but not more than 5 cm. Cancer has also spread to 1 to 3 axillary lymph nodes, to internal mammary lymph nodes or to these two regions.

Yes

The tumor is more than 5 cm long.

Stage 3a

The tumor measures 5 cm or less or no tumors are detected in the breast. Cancer cells are observed in 4 to 9 axillary lymph nodes or in internal mammary lymph nodes but not in axillary lymph nodes.

Yes

The tumor is more than 5 cm long. Cancer has also spread to 1 to 9 axillary lymph nodes or internal mammary lymph nodes, or it may have spread to 1 to 3 axillary ganglia and internal mammary glands.

Stadium 3b

The tumor invaded the muscles of the chest wall or the skin or both. Cancer may also have spread to 1 to 9 axillary lymph nodes or internal mammary lymph nodes, or it may have spread to 1 to 3 axillary ganglia and internal mammary glands.

Yes

It's inflammatory breast cancer.

Stadium 3c

One of the following statements applies:

The cancer spread to at least 10 axillary lymph nodes or lymph nodes under the clavicle (infra-supraclavicular ganglia).

The cancer has spread to more than 3 axillary lymph nodes and internal mammary lymph nodes.

The cancer spread to the lymph nodes above the clavicle (SUS-supraclavicular glands).

Stage 4

Cancer has spread to other parts of the body (remote metastasis), such as bone, liver, lungs or brain. We also talk about metastatic breast cancer.

Breast cancer recurrence

The recurrence of breast cancer means that the cancer reappears as a result of the treatment. If he reappears at the place where he first started, we are talking about local recidivism. If it reappears in tissues or lymph nodes located near where it first originated, it is referred to as a regional recurrence. It can also reappear in another part of the body: we are talking about relapse or remote metastasis.