Understanding HER2+ metastatic breast cancer

What is HER2+ breast cancer?

All the cells in the body—healthy and cancerous—have HER2 receptors. But HER2+ breast cancer cells have too many HER2 receptors, which make them grow and divide faster than other types of cells. This causes tumors to form.

In metastatic breast cancer, the cancer has spread to other parts of the body, such as the lungs, liver, or bones.

How does my doctor know that my breast cancer is HER2+?

Only a HER2 test will show if your breast cancer is HER2+. This test should be done before any breast cancer treatment is started. KADCYLA has been shown to work only in people with HER2+ breast cancer.

What is HER2-targeted treatment?

Targeted cancer treatments are designed to target specific characteristics of cancer cells, but may also affect healthy cells. They are different from traditional chemotherapy. Chemotherapy kills cells that grow and divide rapidly, regardless of whether they are healthy cells or cancer cells.

HER2-targeted treatments are designed to bind to HER2 receptors to fight cancer cells that have too many HER2 receptors. Keep in mind that healthy cells also have HER2 receptors—just not as many—so these types of treatments can affect healthy cells, too.


Learn about KADCYLA for HER2+ metastatic breast cancer and how well it works.


Understand how KADCYLA is given for metastatic breast cancer.