Breast Cancer Staging

How A Breast Cancer’s Stage Is Determined?

The final stage of your cancer is determined by –
Your complete histopathology report after definitive surgery and few imaging to confirm distant spread

Your pathology report will include information that is used to calculate the stage of the breast cancer — that is, whether it is limited to one area in the breast, or it has spread to healthy tissues inside the breast or to other parts of the body. Your doctor will begin to determine this during surgery to remove the cancer and look at one or more of the underarm lymph nodes, which is where breast cancer tends to travel first. He or she also may order additional blood tests or imaging tests if there is reason to believe the cancer might have spread beyond the breast.

The breast cancer staging system, called the TNM system, is overseen by the American Joint Committee on Cancer (AJCC). The AJCC is a group of cancer experts who oversee how cancer is classified and communicated. This is to ensure that all doctors and treatment facilities are describing cancer in a uniform way so that the treatment results of all people can be compared and understood.

In the past, stage number was calculated based on just three clinical characteristics, T, N, and M:

Numbers or letters after T, N, and M give more details about each characteristic. Higher numbers mean the cancer is more advanced. Jump to more detailed information about the TNM system.

In 2018, the AJCC updated the breast cancer staging guidelines to add other cancer characteristics to the T, N, M system to determine a cancer’s stage:

Tumour grade: a measurement of how much the cancer cells look like normal cells

Oestrogen- and progesterone-receptor status: do the cancer cells have receptors for the hormones oestrogen and progesterone?

HER2 status: are the cancer cells making too much of the HER2 protein?

Oncotype DX score, if the cancer is oestrogen-receptor-positive, HER2-negative, and there is no cancer in the lymph nodes

Adding information about tumour grade, hormone-receptor status, HER2 status, and possibly Oncotype DX test results has made determining the stage of a breast cancer more complex, but also more accurate.

In general, according to experts, the new staging system classifies the tumor as per its overall aggressiveness e.g triple-negative breast cancer (estrogen-receptor-negative, progesterone-receptor-negative, and HER2-negative) at a higher stage and classifies most hormone-receptor-positive breast cancer at a lower stage.

The updated AJCC breast cancer staging guidelines have made determining the stage of a cancer a more complicated but accurate process. So, the characteristics of each stage below are somewhat generalized.

AJCC’s TNM staging groups breast cancer patients into stages from stage 0 to stage 4 .

To see all the possible characteristics of each stage, you can review the AJCC Breast Cancer Staging Guidelines (PDF) online.

Clinical staging –

You also may see or hear certain words used to describe the stage of the breast cancer when you visit a surgeon before surgery.

Local: The cancer is confined within the breast.

Regional: The lymph nodes, primarily those in the armpit, are involved.

Distant: The cancer is found in other parts of the body as well.

At this time of your consultation,  you are usually staged on clinical examinational and on the basis of your various imaging. These are called clinical staging.

These clinical stages are – early Breast Cancer ( EBC) , Locally advanced breast cancer ( LABC) and metastatic Breast Cancer ( MBC)

Early Breast Cancer ( EBC)–  Breast cancer is said to be in early stage when the tumour is confined to breast tissue only and not spread to armpit nodes ,not adherent to underlying chest wall, when overlying skin is free . It has the best prognosis.

Locally advanced breast cancer ( LABC)- when tumour is adherent to underlying chest wall and/or overlying skin , when it has spread to locoregional lymph nodes like under armpits and /or inside chest ,then its labelled as locally advanced Breast cancer. In this case , it may be needed to downstage the disease by giving you few therapies like chemotherapy or hormonal therapy before surgery.

Metastatic Breast Cancer ( MBC)- when breast cancer spread to other distant body parts other than breast and local Lymph nodes , its staged as Metastatic Breast Cancer. The common body organs to get affected are bones, Lungs, Liver and brain. The prognosis in this stage is relatively poor. The response to therapy and life expectancy depends upon type of breast cancer, the extent of spread and overall general condition at the time of presentation.