Can you tell me what exactly is metastatic breast cancer?

Cancer 'elsewhere': Metastatic cancer is cancer that has spread from its organ of origin to another part of the body. For example, the most common sites of metastases for breast cancer are the lungs, liver, and bone. Most breast cancers, when caught early and treated in a timely manner, do not ever spread to other organs.

Stage 4 cancer: There are 4 stages of cancer, with stage 4 being the highest. Stage 4 means cancer has spread outside of the place it started and can't be removed by surgery. Women with stage 4, or metastatic, breast cancer cannot usually be cured. The cancer can be treated to keep it under control, often for years, but it depends on the type of breast cancer.

Distant disease: This means the breast cancer cells have traveled outside of the breast to other locations in the body.