Invasive breast cancer occurs when cancer cells from inside the milk ducts or lobules break out into nearby breast tissue.
Cancer cells can travel from the breast to other parts of the body through the blood stream or the lymphatic system. They may travel early in the process when a tumor is small or later when a tumor is large.
If breast cancer spreads, the lymph nodes in the underarm area (the axillary lymph nodes) are the first place it's likely to go.
Learn about treatment for invasive breast cancer.
Metastatic breast cancer (also called stage IV or advanced breast cancer) is invasive breast cancer that has spread beyond the breast and axillary lymph nodes to other parts of the body (most often the bones, lungs, liver or brain).
Metastatic breast cancer is not a specific type of breast cancer, but rather the most advanced stage of breast cancer.
Learn about treatment for metastatic breast cancer.
The prognosis (chances for survival) after invasive breast cancer depend on each person’s diagnosis and treatment.
For example, people diagnosed with early breast cancers have a better prognosis than those diagnosed with more advanced breast cancers.
Learn more about factors that affect prognosis.
Treatment for invasive breast cancer usually involves some combination of surgery, radiation therapy, chemotherapy, hormone therapy and/or HER2-targeted therapy.
The order of therapies and the specific treatments depend on the cancer stage and the characteristics of the tumor (such as hormone receptor status).
Learn more about treatment.
Learn more about breast cancer stage.
Learn more about factors that affect breast cancer treatment.
Facts for Life: Types of Breast Cancer Tumors
How has having breast cancer changed your outlook?