Dr. Roussos Torres on the Potential for Immunotherapy in HER2+ Breast Cancer

Evanthia Roussos Torres, MD, oncology fellow, Johns Hopkins University School of Medicine, discusses the promise of immunotherapy in the treatment of patients with HER2-positive breast cancer.

Currently, most preclinical work and clinical trials of immunotherapy in breast cancer are in patients with triple-negative disease. Although immunotherapy has not been as well studied in HER2-positive breast cancer, Roussos Torres says that there is reason to believe that a robust response can be seen in this population with a combinatorial approach incorporating checkpoint inhibitors.

In a study of HER2-positive tumors, the epigenetic modulator entinostat is showing signals of improvement in the immunosuppressive tumor microenvironment of mice, making it more amenable to checkpoint inhibition. Investigators used epigenetic modulation to affect activation and trafficking of myeloid-derived suppressor cells, which are known to alter the immunogenicity of the tumor microenvironment. This approach may improve response rates in HER2-positive breast cancer, Roussos Torres says, but more work needs to be done.