 3. Diagnosis of hormone receptor positive HR, HER2 negative breast cancer. To fulfill the requirement for HR disease, a breast cancer must express, by immunohistochemistry IHC, at least one of the hormone receptors estrogen receptor ER, progesterone receptor PR. To fulfill the requirement for HER2 negative disease, a breast cancer must not demonstrate over-expression of HER2 by either IHC or fluorescence in-situ hybridization FISH; 