What are the four stages of breast cancer
The four stages of breast cancer are as follows:
Stage 0: Also known as carcinoma in situ, this stage refers to the presence of abnormal cells that are confined to the milk ducts or lobules of the breast. At this stage, cancer cells have not invaded surrounding tissues or spread to other parts of the body.
Stage I: Cancer is at an early stage and has not spread beyond the breast. Tumors are small and have not invaded nearby lymph nodes.
Stage II: Cancer cells have spread beyond the breast and nearby lymph nodes may be affected. Stage II is further divided into subcategories: Stage IIA, where the tumor is small and may or may not have spread to lymph nodes, and Stage IIB, where the tumor is larger or has spread to 1 to 3 lymph nodes.
Stage III: Cancer has spread to nearby lymph nodes and may have invaded nearby tissues or structures. Stage III is further divided into subcategories: Stage IIIA, where the tumor may be any size and has spread to 4 to 9 nearby lymph nodes or has invaded nearby structures like the chest wall or skin; Stage IIIB, where the tumor has invaded the chest wall or skin and may or may not have spread to nearby lymph nodes; and Stage IIIC, where the tumor may have spread to 10 or more nearby lymph nodes or to lymph nodes above or below the collarbone.
Stage IV: Cancer has spread to other organs or distant parts of the body, such as the bones, liver, lungs, or brain. At this stage, breast cancer is considered advanced or metastatic.