What is breast cancer?

Anyone could be a victim of breast cancer as the breast cells start to grow abnormally without a warning sign. The type of cancer is determined by the nature of cells that grow in the breast. Breast cancer may originate in any part of the breast, like the ducts, lobules, and connective tissues. Usually, it is the lobules or ducts that are affected first.

Why is it necessary to determine the stage of breast cancer?

The severity of breast cancer is determined by its characteristics, like how big the cancer is and whether it has hormone receptors or not. Knowing its stages is important as it will help the doctor understand the prognosis and probable outcome. This will also help figure out the right treatment options and assess if the affected person is fit for certain clinical trials.

How can you determine the stages of breast cancer?

The stages of breast cancer are expressed on a scale of 0 to IV, where 0 is non-invasive and the cancer is still restricted to the original location; whereas stage IV is invasive and the cancer has spread to other body parts. Pathology reports will have information about the calculation of the stage. This helps determine if it is restricted to the breast or has moved out. The staging system is called the TNM system which stands for Tumor, Node, and Metastasis, respectively. This is overseen by the American Joint Committee on Cancer (AJCC).

In all, there are four stages of breast cancer:

• Stage 0 describes non-invasive cancers. During this stage, there is no evidence that the cancer cells have broken out from the origin.
• Stage I stands for invasive breast cancer wherein the cells breakthrough or invade the normal surrounding tissues. Stage 1 has two types: IA and IB. IA refers to invasive breast cancer where the tumor is up to two centimeters and cancer remains inside the breast; no lymph nodes are affected. On the other hand, stage IB is invasive breast cancer where no tumor exists, but there are small cancer cell groups (less than two millimeters) in the lymph nodes. In stage I, a microscopic invasion may be possible. This means that cancer cells have just begun to move into the tissues outside the duct or lobule linings.
• Stage II can also be of two types: IIA and IIB, namely. Stage IIA is an invasive breast cancer where there may not be a tumor or a very small one, if at all there is one. Stage IIB is where the tumor is bigger, almost the size of a lime or walnut, which may be in lymph nodes.
• Stage III is divided into three sub-categories: IIIA, IIIB, and IIIC. Here, cancer may not have moved to the organs or bones, but it is advanced and harder to overcome. In IIIA, cancer can be detected in almost nine lymph nodes or it may have spread to lymph nodes deep inside the breast. IIIB implies that the tumor has penetrated the skin surrounding the breast or chest wall. Lastly, IIIC implies that cancer has been detected in 10 or more lymph nodes and has spread beyond the collarbone.
• Stage IV refers to invasive breast cancer which goes beyond the breast into the surrounding lymph nodes and other organs like the lungs, skin, liver, bones, or brain. This stage is often called the advanced or “metastatic” stage. Sometimes, the affected person could be at stage IV in the first diagnosis itself.