What The Stages of Breast Cancer Mean, Including Each One’s Estimated Survival Rate

What you need to know, from Stage 0 to Stage 4.


Yamkela Mdaka |

Breast cancer is the foremost cancer affecting women in South Africa, according to the 2018 Discovery Health Healthcare Claims Tracker report. Approximately 1 in 28 South African women will develop breast cancer during their lifetime. Breast cancer, together with cervical cancer, has been classified as a national priority particularly because of the increasing incidences happening throughout the country each year. 

Not all lumps are breast cancer 

Prof. Carol Benn, breast cancer specialist who also heads up the breast cancer centres at Helen Joseph Hospital and Netcare Milpark Hospital, says that while the stats around breast cancer may be frightening for women, it’s important to remember a few things. 

“Most breast lumps are benign (only one in 10 lumps on the breast are malignant) and breast cancer can be cured,” Prof. Benn says. 

READ MORE: 11 Symptoms Of Breast Cancer In Women That Aren’t Lumps

“Breast cancer is less common in women under 30 years old and 90% of them are sporadic. This means that the cancers arise in any women, at any time and are the result of the interplay of the risk factors.”

Genetic factors 

She adds that genetic causes of breast cancer account for 10% of all breast cancer cases. “Breast cancer is inherited as an autosomal dominant trait (gene) with limited penetrance and expressivity,” she explains.

*Say what?* “This means that the gene can be transmitted by either mother or father and also that some family members can transmit the genetic trait without actually developing the breast cancer themselves.”

Breast cancer staging

A breast cancer stage speaks to the extent of one’s cancer. The reason doctors categorise breast cancer into stages is so that they can understand how serious your specific case is, and through that, give you the best treatment options available. It’s also a way for them to identify any clinical trials that might be options for you to consider. 

There are several things doctors do to determine one’s cancer stage, including lab tests and X-rays. Your cancer will always be referred to by the stage it was given when it was initially diagnosed. All other new information after that gets put on to that original stage, so your stage of diagnosis will never change. 

READ MORE: 8 Breast Cancer Myths You NEED To Stop Believing

As we all know, for any cancer, early detection has the highest survival rate. But cancer not being found early does not necessarily spell the end of your life. 

When staging breast cancer, there are seven key things that specialists use as the criteria. The American Cancer Society outlines these as follows: 

  • The size of the tumour and how it has spread to nearby areas.
  • Has the cancer spread to the lymph nodes, and how many?
  • If the cancer has spread to the other organs in your body. 
  • Does the cancer have a protein called an estrogen receptor?
  • Does the cancer has a protein called a progesterone receptor?
  • Is the cancer making a protein called Her2, and is it making too much of this? 
  • How much the cancer cells look like normal cells.

Stage 0

This is the earliest form of breast cancer and is described as a non-invasive cancer. It means that the disease hasn’t spread to the surrounding tissue of the breast and is only present in the ducts of the breast tissue. 

Stage 1 (I)

This stage of breast cancer is categorised into two sub-stages, namely: IA and IB. Simply put, the IA stage means that the tumour is 2cm or smaller. According to the Canadian Cancer Society, stage IB also means that the tumour is 2cm or smaller and that sometimes it can’t be seen at all in the breast. This stage also means that a few cells are found in the lymph nodes (an organ of the lymphatic system which is widely present through the body), but each lymph node that has a cancer cell in it is not longer than 2mm. 

Stage 2 (II) 

IIA and IIB are the two sub-stages of stage II cancer. IIA means that the tumour is between 2cm and 5cm in size. It also means that the cancer has spread into 1 to 3 lymph nodes under one’s arm and/or lymph nodes around the breastbone in the chest. 

Stage 3 (III) 

Out of all the stages of breast cancer, this is the only stage that has three sub-stages. These include stages IIIA, IIIB, IIIC. In short, stage IIIA describes a tumour that is 5cm or smaller, and sometimes no tumour is visible in the breast at all. Cancer cells in this stage will be found in about 4 to 9 axillary lymph nodes, or internal mammary lymph nodes, but never in both. 

However, if the cancer cells are found in both – then it will have spread to between 1 to 3 axillary lymph nodes and internal mammary lymph nodes. 

READ MORE: Here’s How You Can Lower Your Risk Of Breast Cancer

For stage IIB, the cancer is in either the skin, the muscles of the chest wall, and in other instances – both. Like stage IIA, the cancer might have also spread to between 1 to 9 axillary lymph nodes or internal mammary lymph nodes. And again, if found in both then it might have spread to 1 to 3 axillary lymph nodes and internal mammary lymph nodes. 

And lastly, stage IIIC means that the cancer could have spread to 10 or more lymph nodes below the collarbone, or 10 or more axillary lymph nodes. It could also mean that it spread to the lymph nodes above the collarbone, or that it has spread to 3 axillary lymph nodes and internal mammary nodes. 

Stage 4 (IV) 

This stage of breast cancer is also known as metastatic breast cancer and it means that the cancer has spread throughout your body – this includes areas and organs such as one’s brain, lungs, bones, liver and so on. 

Survival rates 

Let’s take a look at the estimated survival rates of the different stages of breast cancer. Before these numbers make you panic, remember that they are mere estimations based on data from previous patients. No one can ever predict what the outcome will be in an individual’s case. 

Localised: When the cancer hasn’t spread and is limited to where it started.

Survival rate: 99% (*over a 5-year period).

Regional: When the cancer has spread to close-by lymph nodes, organs and tissues.

Survival rate: 85%*

Distant: When the cancer has spread far throughout the body. 

Survival rate: 27%*

READ MORE ON: Breast Cancer Cancer Health Advice