We use immunotherapy in many other cancer types to help increase the immune system’s ability to identify and attack cancer cells. For years, we have not been able to find a way that immunotherapy would benefit women with breast cancer.
In a recent trial, women with untreated metastatic breast cancer were randomized to receive chemotherapy, abraxane, either with or without an immunotherapy, atezolizumab (Tecentriq). In patients that stained positive for immune sensitive tumors (PD-L1 stain), patients actually lived significantly longer when the Tecentriq was added to chemotherapy (25 vs 15 months).
In March 2019, the FDA granted accelerated approval to atezolizumab in combination with chemotherapy for patients with unresectable locally advanced or metastatic triple negative breast cancer whose tumors express PD-L1 (> 1%). This is a very exciting development and is the first approval of immunotherapy for breast cancer patients. Any patient should be asking their doctor to test their tumor for PD-L1 going forward if they have metastatic breast cancer.