CD274 and breast cancer: There are also extrinsic factors such as patient characteristics and lifestyle that can lead to resistance as well. Strategies to overcome resistance to immunotherapy is an ongoing investigation. While there is significant improvement in responses with combination dual immunotherapy, addition of targeted therapy, or PD-L1 down regulators/ inhibitors that are being used in other cancers, there needs to be further research in breast cancer to identify ways to overcome immunotherapy resistance [28].