Based on the evidence, promising permutations for combined therapy may include FGFR inhibitors with endocrine therapy in breast cancer [123, 139], leading to trials such as AZD4547 & Anastrozole or Letrozole (NSAIs) in ER+ Breast Cancer Patients who have progressed on non-steroidal aromatase inhibitors. This evidence concerns the gene CYP19A1 and breast cancer.