Metastatic breast cancer, also called stage IV breast cancer or advanced breast cancer, is breast cancer that has spread to parts of the body other than the breast and underarm area. The spread of cancer is also called metastasis or mets for short. The most common areas that breast cancer spreads to are the bones, liver, lungs, and brain. When breast cancer spreads to an area, it is still breast cancer, not bone cancer, liver cancer, etc. This is important because the cancer responds to treatments designed for breast cancer, not for bone or liver cancer.
The goals for treating metastatic breast cancer are to stop/slow the growth of the cancer and reduce/eliminate symptoms. Metastatic breast cancer is not curable and treatment is continuous, sometimes with short breaks. Because patients receive continuous treatment, quality of life is an important part of treatment decisions (i.e. your treatment should not make you sicker than your disease). Most patients receive hormone therapy as a first option, then chemo using one chemo drug at at time when hormone therapy stops working. (Earlier stage cancer is often treated with combinations of multiple chemotherapy drugs.) Radiation and surgery are also sometimes used.
The experience of metastatic breast cancer can vary greatly depending on what parts of the body are affected. For example, metastatic breast cancer to the bone can cause bone pain and mobility limitations, while metastasis to the liver can cause jaundice and digestive problems.
While the prognosis for metastatic breast cancer is poor, it is very difficult for doctors to predict how long a particular patient will live with the disease. In general, patients who have metastasis to the bones ONLY live longer than those whose cancer has spread to other locations. Survival statistics for metastatic breast cancer are difficult to interpret and depend on many factors including other diseases the patient has, age, which sites are affected by cancer, etc. Also my doctor tells me that the 5 year survival rate is already five years old. In the four months since my diagnosis, two new drugs have been FDA approved to treat metastatic breast cancer.
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