What Are the Stages of Breast Cancer?

• Early stage or stage 0 breast cancer is when the disease is localized to the breast with no evidence of spread to the lymph nodes (carcinoma in situ).
• Stage 1 breast cancer: The cancer is two centimeters or less in size and it hasn't spread anywhere.
• Stage 2A breast cancer is a tumor smaller than two centimeters across with lymph node involvement or a tumor that is larger than two but less than five centimeters across without underarm lymph node involvement.
• Stage 2B is a tumor that is greater than five centimeters across without underarm lymph nodes testing positive for cancer or a tumor that is larger than two but less than five centimeters across with lymph node involvement.
• Advanced breast cancer (metastatic) results after cancer cells spread to the lymph nodes and to other parts of the body.
• Stage 3A breast cancer is also called locally advanced breast cancer. The tumor is larger than five centimeters and has spread to the lymph nodes under the arm, or a tumor that is any size with cancerous lymph nodes that adhere to one another or surrounding tissue.
• Stage 3B breast cancer is a tumor of any size that has spread to the skin, chest wall or internal mammary lymph nodes (located beneath the breast and inside the chest).
• Stage 3C breast cancer is a tumor of any size that has spread more extensively and involves more lymph node invasion.
• Stage 4 breast cancer is defined as a tumor, regardless of size, that has spread to places far away from the breast, such as bones, lungs, liver, brain or distant lymph nodes.