What is Metastatic Breast Cancer?


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Metastatic breast cancer occurs when breast cancer cells travel from the breast to another part of the body such as the bones, liver, lungs, or brain. Metastatic breast cancer is also referred to as Stage IV breast cancer.

A second breast cancer that develops in the same or the other breast is not metastatic breast cancer. And having cancer cells in the lymph nodes does not mean your cancer is Stage IV, although pathologists sometimes use the term "metastatic to the lymph nodes."

What does it mean to have metastatic breast cancer?

A diagnosis of metastatic breast cancer can be very frightening because it is considered to be incurable. But as treatments improve, metastatic women are living longer and able to have better quality of life. Living with metastatic breast cancer usually involves ongoing treatment -- chemotherapy, hormonal treatment, or radiation.

When is metastatic breast cancer usually diagnosed?

Some women (about six percent) are initially diagnosed at Stage IV. They may already have symptoms such as pain or shortness of breath that cause the doctors to suspect metastatic cancer. Or the metastasis may be discovered during a CT or PET scan as part of the initial workup for breast cancer.

Most women who become metastatic are diagnosed later, anytime from several months to years after they were initially treated for early stage cancer.

What causes metastatic breast cancer?

We still do not understand why some cancers become metastatic, especially those that are diagnosed years after the first breast cancer. In the past, doctors believed that cancer progressed in a linear manner and that women with positive lymph nodes were more likely to become metastatic. Now researchers are focusing more on genetics and the microbiology of breast cancer. They are trying to learn why some cancers behave more aggressively, what causes cancer cells to grow in different parts of the body, and what treatments can be developed to stop that process.

Where can I get more information about metastatic breast cancer?

Call SHARE's Metastatic Breast Cancer Helpline. Our breast cancer helpline has trained metastatic peers ranging in age from early thirties to eighty. Some have been living with metastatic disease for many years. We can answer your questions, help you figure out your options, and give you realistic hope and support. Call us at 844-ASK-SHARE (844-275-7427).

Our bi-monthly e-newsletter provides information for women living with metastatic breast cancer.

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