In the last decade, breast cancer has affected many women, and most of them have gone through various treatment therapies to recover from this chronic ailment. The best way to start treatment is by knowing the stage of breast cancer as the doctors will decide on the treatment when they know the stage.

There are five stages of breast cancer, which start from stage 0 and go on to stage IV:

Stage 0
In stage 0 of breast cancer, one cannot see any evidence of cancer cells. It usually describes non-invasive breast cancers. This may include ductal carcinoma in situ, which means the lining of a breast duct consists of cancer cells. It may otherwise mean lobular carcinoma in situ, wherein the breast lobules show the development of abnormal cells, or it may be Paget’s disease of the breast that does not have any invasive cancer cells.

Stage I
With the initiation of stage I of breast cancer, the development of invasive breast cancer starts. This implies that cancer starts invading the normal cells that surround the tissue of the breast. Stage I is generally further divided into two categories:

• Stage IA : This stage means that the spread of cancer has increased to fatty breast tissue. At this stage, either there will be no tumor or the size of the tumor will be very small, about two centimeters. There are no lymph nodes involved up to this stage of breast cancer.
• Stage IB : At this stage, you can observe a few cancer cells infecting lymph nodes. The size of the group of cancer cells at this stage is less than two millimeters in the lymph nodes.

Stage II
This stage describes the growth and spread of cancer cells. This stage is also divided into two parts:

• Stage IIA : At this stage, there will be no tumor, or if you can observe a tumor, the size of that tumor will be no more than two centimeters. Cancer cells spread toward one to three axillary lymph nodes surrounding the breastbone.
• Stage IIB : At this stage, the size of the tumor will be larger than two centimeters but smaller than five centimeters. The cancer cells will spread to the axillary lymph nodes or internal mammary lymph nodes.

Stage III
At this stage, cancer is considered advanced, but it may not spread to different organs or bones. There are three categories of this stage:

• Stage IIIA : At this stage, one can sometimes observe a large tumor in the breast. The cancer cells may spread to all the lymph nodes from the underarm to the collarbone.
• Stage IIIB : This stage refers to the spread of cancer to the chest or the skin of the breast.
• Stage IIIC : At this stage, the cancer cells spread above or below the collarbone. Some of the lymph nodes outside the breast may also get infected at this stage.

Stage IV
This is the last stage of cancer, and it means that cancer has spread to all other parts of the body, such as bones and lungs.

One can start the treatment for breast cancer based on the stage of cancer they are suffering from.